We acclimated adults of two viviparous (Phrynocephalus guinanens& and P. vlangalii) and one oviparous (P. versicolor) species of toad-headed lizards (Agamidae) to 28 ℃, 33 ℃ and 38 ℃ to examine whether therm...We acclimated adults of two viviparous (Phrynocephalus guinanens& and P. vlangalii) and one oviparous (P. versicolor) species of toad-headed lizards (Agamidae) to 28 ℃, 33 ℃ and 38 ℃ to examine whether thermal preference (preferred body temperature, Tp) and thermal tolerance (critical thermal minimum, CTMin; critical thermal maximum, CTMax) were affected by acclimation temperature, and correlate with body size and habitat use. Both Tp and CTMax were highest in P. versicolor and lowest in P. vlangalii, with P. guinanensis in between. The two viviparous species did not differ in CTMin and thermal tolerance range, and they both were more resistant to low temperatures and had a wider range of thermal tolerance than the oviparous species. Both CTMin and CTMax shifted upward as acclimation temperature increased in all the three species. Tp was higher in the lizards acclimated to 33 ℃ than in those to 28 ℃ or 38 ℃. The range of thermal tolerance was wider in the lizards acclimated to 28 ℃ than in those to 33 ℃ or 38 ℃. The data showed that: 1) thermal preference and tolerance were affected by acclimation temperature, and differed among the three species of Phrynocephalus lizards with different body sizes and habitat uses; 2) both Tp and CTMax were higher in the species exchanging heat more rapidly with the environment, and CTMin was higher in the species using warmer habitats during the active season; and 3) thermal preference and tolerance might correlat with body size and habitat use in Phrynocephalus lizards.展开更多
Animal body size variation is of particular interest in evolutionary biology,but the genetic basis remains largely unknown.Previous studies have shown the presence of two parallel evolutionary genetic clusters within ...Animal body size variation is of particular interest in evolutionary biology,but the genetic basis remains largely unknown.Previous studies have shown the presence of two parallel evolutionary genetic clusters within the fish genus Epinephelus with evident divergence in body size,providing an excellent opportunity to investigate the genetic basis of body size variation in vertebrates.Herein,we performed phylotranscriptomic analysis and reconstructed the phylogeny of 13 epinephelids originating from the South China Sea.Two genetic clades with an estimated divergence time of approximately 15.4 million years ago were correlated with large and small body size,respectively.A total of 180 rapidly evolving genes and two positively selected genes were identified between the two groups.Functional enrichment analyses of these candidate genes revealed distinct enrichment categories between the two groups.These pathways and genes may play important roles in body size variation in groupers through complex regulatory networks.Based on our results,we speculate that the ancestors of the two divergent groups of groupers may have adapted to different environments through habitat selection,leading to genetic variations in metabolic patterns,organ development,and lifespan,resulting in body size divergence between the two locally adapted populations.These findings provide important insights into the genetic mechanisms underlying body size variation in groupers and species differentiation.展开更多
[Objective]The research aimed to study the polymorphism of intron 1 and its effects on prolactin(PRL) gene and body size traits of Jingjiang Partridge Duck.[Method]Taking 96 Jingjiang partridge ducks as materials,th...[Objective]The research aimed to study the polymorphism of intron 1 and its effects on prolactin(PRL) gene and body size traits of Jingjiang Partridge Duck.[Method]Taking 96 Jingjiang partridge ducks as materials,the polymorphism of intron 1 of PRL gene was detected by PCR-RFLP method.And the relationship between the gene polymorphism and body size traits was analyzed.[Result]Intron 1 in PRL gene of Jingjiang Partridge Duck had sequence polymorphism.Two kinds of genotypes(AB and BB) were detected by DraⅠrestriction and genotype BB was dominant in population(91.67%).The results of Chi-square test indicated that this site was in Hardy-Weinberg equilibrium in Jingjiang Duck(P 〉0.05).The results of least square analysis showed that the ducks with AB genotype had larger pelvis breadth(P 〈0.01) but smaller chest measurement(P 〈0.05) than those of BB ducks.[Conclusion]It was preliminarily concluded that PRL gene could be regarded as useful candidate gene(marker) for part of body size traits of Jingjiang Partridge Duck and part of body size traits can be improved by allele selection.展开更多
In anurans, the outcomes of male-male contests and female choice are often associated with body size. In some species, males evaluate an opponent’s fighting ability and females evaluate male quality on the basis of m...In anurans, the outcomes of male-male contests and female choice are often associated with body size. In some species, males evaluate an opponent’s fighting ability and females evaluate male quality on the basis of male communication signals, which are thought to reflect information concerning male body size. Nevertheless, previous studies reveal that male call structure is not always correlated with body size. In the present study we investigated the relationships between body size and call structure in the large treefrog, Rhacophorus dennysi, as well as the relationship of its calling behavior with air temperature and humidity. The results show that both the dominant and fundamental frequencies are negatively correlated with body size, while inter-note intervals are positively correlated with body size, indicating that call characters could reflect body size in this species.Additionally, calling in this tropical species exhibits a circadian rhythm insofar as relatively high temperature and low humidity during the day is associated with less vocal behavior. Thus, individual variations in call structure are mainly dependent on body size while the temporal rhythm of calling activity is affected by environmental conditions in large treefrogs.展开更多
Arctodiaptomus salinus inhabits water bodies across Eurasia and North Africa. Based on our own data and that from the literature, we analyzed the influences of several factors on the intra- and inter-population variab...Arctodiaptomus salinus inhabits water bodies across Eurasia and North Africa. Based on our own data and that from the literature, we analyzed the influences of several factors on the intra- and inter-population variability of this species. A strong negative linear correlation between temperature and average body size in the Crimean and African populations was found, in which the parameters might be influenced by salinity. Meanwhile, a significant negative correlation between female body size and the altitude of habitats was found by comparing body size in populations from different regions. Individuals from environments with highly varying abiotic parameters, e.g. temporary reservoirs, had a larger body size than individuals from permanent water bodies. The changes in average body mass in populations were at 11.4 times, whereas, those in individual metabolic activities were at 6.2 times. Moreover, two size groups of A. salinus in the Crimean and the Siberian lakes were observed. The ratio of female length to male length fluctuated between 1.02 and 1.30. The average size of A. salinus in populations and its variations were determined by both genetic and environmental factors. However, the parities of these factors were unequal in either spatial or temporal scales.展开更多
Gene expression variation can be considered as a phenotype,and it plays an important role in both acclimation and adaption.However,genetic variation of gene expression received much less attention than traditional com...Gene expression variation can be considered as a phenotype,and it plays an important role in both acclimation and adaption.However,genetic variation of gene expression received much less attention than traditional commercial traits in aquaculture.To estimate the genetic variation and heritability of gene transcription in clam Meretrix petechialis,five Vibrio resistance-related genes were selected for gene expression analysis in the digestive gland,and an animal linear model was used to analyze data from quantitative real-time PCR(qRT-PCR).Among the five genes,BIRC7 showed significant additive genetic variations,the heritability of this gene of 12-month-and 15-month-old clams were 0.84±0.32 and 0.91±0.34,respectively.The heritability of other four genes(Bax,NFIL3,Big-Def,and CTL9)expression were low-tomoderate but not significantly expressed.Additionally,no significant phenotypic and genetic correlations between the BIRC7 transcription trait and body size were detected.This study highlights that certain gene expression variation is heritable and provides a reference for indirect selection of M.petechialis with high Vibrio resistance.展开更多
A 21-d laboratory experiment was conducted to study, the phosphorus (P) utilization of two different diets by redlip mullet Liza haematocheila T. & S. Sand-filtered water in salinity 30 and temperatare 25℃ was use...A 21-d laboratory experiment was conducted to study, the phosphorus (P) utilization of two different diets by redlip mullet Liza haematocheila T. & S. Sand-filtered water in salinity 30 and temperatare 25℃ was used. Twenty-nine fish individuals were divided into three groups: 11 to group 1 (G1) fed on diet 1, 11 to group 2 (G2) fed on diet 2, and 7 to contrast group. Diet 1 was a commercial feed, more valuable in nutrition than diet 2 that similar to natural detritus. The results show the intake phosphorus (IP) of G1 was significantly higher than that of G2, and both increased linearly with body size at a certain amount of diet. The retention phosphorus (RP) in fish of G1 was lower than G2. The relationship between retention phosphorus and body size was positive and stronger in G2. Significant difference in faecal phosphorus (FP) was found between G1 and G2. Body size significantly impacted the excretion phosphorus (EP) in G1 but G2. The loss of intake phosphorus in G1 was 10.83-20.27 mg per g fish weight gain, higher than that in G2 for 6.63-9.56. Of the phosphorus, about 10% was allocated into growth, 50% in faeces, and the rest lost in excretion. The main part of phosphorus was lost in faeces but excretion. The phosphorus budget of the fish could be described as 100IP = 7.40RP + 47.39FP + 36.63EP (Diet 1) or 100IP = 11.93RP + 56.64FP + 21.76EP (Diet 2).展开更多
In anurans, body size and age of individuals generally affect male mating success. To test whether body size and age have effects on male mating success in the foam-nesting treefrog Polypedates megacephalus, a species...In anurans, body size and age of individuals generally affect male mating success. To test whether body size and age have effects on male mating success in the foam-nesting treefrog Polypedates megacephalus, a species widely distributed in China, we analyzed differences in body size and age between mated and unmated males for three populations using a Generalized Linear Mixed Model(GLMM). The results showed that mated males did not exhibit larger body size and older age than unmated males, suggesting that large and/or old male individuals did not have greater mating success than small and/or young males. Moreover, we also found a non-significant size-assortative mating pattern for all populations. Our findings suggest that body size and age of the foam-nesting treefrog do not affect male mating success.展开更多
This study was performed to evaluate the effect of temperature on the carbon(C),nitrogen(N),and phosphorus(P)nu-trient budgets of adult steelhead trout(Oncorhynchus mykiss)with different body sizes.A complete two-fact...This study was performed to evaluate the effect of temperature on the carbon(C),nitrogen(N),and phosphorus(P)nu-trient budgets of adult steelhead trout(Oncorhynchus mykiss)with different body sizes.A complete two-factor experiment was con-ducted at four temperatures,i.e.,9(T9),13(T13),16(T1℃℃℃6),and 19(T19);and three body sizes,℃i.e.,0.65 kg±0.02 kg(S1),1.22 kg±0.06 kg(S2),and 2.05 kg±0.09 kg(S3).The following properties of steelhead trout were determined:C,N,and P nutrient budgets;feed intake rate;fecal production rate;oxygen consumption rate;ammonia excretion rate;phosphorus excretion rate;scope of the growth of C,N,and P;and absorption efficiency of C,N,and P.Results showed no significant interaction between temperature and body size in terms of the nutrient budgets of steelhead trout.However,temperature and body size played important separate roles in the nutrient budgets except for the absorption efficiency of nitrogen.The feed intake rate,fecal production rate,ammonia excretion rate,phosphorus excretion rate,and scope of the growth of C,N,and P were the highest in the T16 treatments.The absorption effi-ciency of C and P decreased as temperature increased.Nonlinear multiple regression results indicated that 15 was the approximate℃optimal temperature for the feeding and growth of steelhead trout.The feed intake rate,fecal production rate,oxygen consumption rate,ammonia excretion rate,phosphorus excretion rate,and scope of the growth of C,N,and P per unit of the body weight of fish decreased as body size increased.The absorption efficiency of C increased as body weight increased,and the absorption efficiencies of P in the S2 and S3 treatments were significantly higher than those in the S1 treatment.During the culture of steelhead trout,the daily ratio should be adjusted with changes in the temperature and body size of fish.Furthermore,managers should focus on the risk of hypoxia at high water temperatures.展开更多
Nonlinear phenomena are commonly shown in the vocalization of animals and exerts different adaptive functions.Although some studies have pointed out that nonlinear phenomena can enhance the individual identification o...Nonlinear phenomena are commonly shown in the vocalization of animals and exerts different adaptive functions.Although some studies have pointed out that nonlinear phenomena can enhance the individual identification of male Odorrana tormota,whether the nonlinear phenomena play a specific role in the sexual selection of O.tormota remain unclear.Here we presented evidence that there was a significant negative correlation(Pearson:n=30,r=0.65,P<0.001)between the nonlinear phenomena content and snout-vent length in the male O.tormota,and two-choice amplexus experiments showed that female O.tormota preferred male with smaller body size containing higher nonlinear phenomena content in its calls.Phonotaxis experiments also revealed that females preferred calls with higher nonlinear phenomena content.Additionally,compared to the calls with lower nonlinear phenomena content and higher fundamental frequency,there was shorter response time in phonotactic behaviour of female induced by the calls with higher nonlinear phenomena content and lower fundamental frequency.We argue that the nonlinear phenomena content in the calls of male O.tormota can convey its body size information and may provide important clues for female frogs in darkened surroundings to identify males’body size during mate choice,meanwhile,higher nonlinear phenomena content in males’calls may increase the attractiveness of males to females.The results of this study provide confirmation that,for O.tormota,nonlinear phenomena have specific function in mate choice.展开更多
Variation in body size and sexual size dimorphism(SSD) can have important consequences for animal ecology, behavior, population dynamics and the evolution of life-history traits. Organisms are expected to be larger ...Variation in body size and sexual size dimorphism(SSD) can have important consequences for animal ecology, behavior, population dynamics and the evolution of life-history traits. Organisms are expected to be larger in colder climate(i.e., Bergmann's rule) and SSD varies with body size(i.e., Rensch's rule). However, the underlying mechanisms are still elusive. The plateau brown frog(Rana kukunoris), a medium-sized anuran species with femalebiased SSD, is endemic to the Qinghai-Tibetan Plateau(QTP). From 1797 m(Maoxiang'ping) to 3453 m(Heihe'qiao) in the eastern margin of the QTP, we surveyed 10 populations of R. kukunoris and collected phalanges and snout vent length(SVL) data for 258 adult individuals(199 males versus 59 females). Based on these data, we explored how body size and SSD varying along the altitudinal gradient and examined the corresponding effects of temperature. We found body size to be larger at higher altitude for males but not for females, with likely effects from the temperature on the variation in male body size. Sex differences in growth rates may be the main cause of the variation in SSD. Our results suggested that only males follow the Bergmann's rule and variation in SSD of R. kukunoris do not support the Rensch's rule and its inverse. Therefore, the variations of body size can be different between sexes and the applicability of both Bergmann's rule and Rensch's rule should depend on species and environment where they live.展开更多
Body size and female reproduction in the water adult females larger than 500 mm SVL and 32 adult males Ledong, Hainan under permit to our laboratory in Hainan monitor lizard (Varanus salvator) were studied. Forty-tw...Body size and female reproduction in the water adult females larger than 500 mm SVL and 32 adult males Ledong, Hainan under permit to our laboratory in Hainan monitor lizard (Varanus salvator) were studied. Forty-two larger than 400 mm SVL were donated by local people in in 2013 and 2014. The largest male and female measured 745 and 755 mm SVL, respectively. The mean SVL was greater in adult females than in adult males. Males had larger heads (head width) than females of the same SVL. The smallest reproductive female in our sample was 565 mm SVL. Females produced a single clutch of 17.1 (10-23) pliable-shelled eggs per breeding season stretching from mid-June and mid-September. Clutch size and clutch mass were all positively related to female SVL. However, there was no significant linear relationship between egg mass and female SVL. Larger females generally produced more eggs, and thus heavier clutches than did smaller ones. There was no significant linear relationship between relative clutch mass and female SVL. Phylogenetic generalized least squares (PGLS) analysis, accounting for phylogenetic relationships, showed that clutch size was positively correlated with mean maternal SVL in varanid lizards. PGLS analysis showed that phylogenetic relationships did not affect clutch (or/and egg) mass and the SVL although there were significant linear relationship between clutch (or/and egg) mass and mean maternal SVL. Therefore, we could draw some general conclusions about the body size and reproductive tactics in varanid lizards that larger females generally produced more eggs, larger eggs and thus heavier clutches than did smaller ones.展开更多
[ Objective] The study was to explore whether the body size, sexual behavior of male donkey had certain correlation with reproductive traits. [ Method] The data of body weight, body size and sexual behavior of male do...[ Objective] The study was to explore whether the body size, sexual behavior of male donkey had certain correlation with reproductive traits. [ Method] The data of body weight, body size and sexual behavior of male donkey during production were collected, combining with the semen quality data of ejaculation volume, density, motility and frozen-thawed semen motility were conducted the statistical analysis. [ Results] ( 1 ) Single ejaculation volume had a positive correlation with body height (r = 0. 423, P = 0. 044) and penis circumference (r = 0. 495, P = 0. 043 ) , and total number of sperm per ejaculate had a positiw: correlation with body weight (r = 0. 444, P = 0. 036) and scrotal circumference (r = 0. 520, P = 0. 039) ; (2) Ejaculation volume was negatively correlated with mount times (r = -0. 159, P = 0. 035) and erection time (r = -0. 181, P = 0. 023), semen density was negatively correlated with mating time (r = - 0.211, P = 0.004), and total sperm count was negatively correlated with erection time (r = - 0. 159 , P = 0. 047). [Condusion ] The quality of semen had a certain correlation with body size, body weight and sexual behavior.展开更多
In order to study the meat development value of princess chicken,the body size traits and slaughter performance of 12-week-old F1 hybrid offspring of princess chicken(♂) and kirin chicken(♀) were measured and the co...In order to study the meat development value of princess chicken,the body size traits and slaughter performance of 12-week-old F1 hybrid offspring of princess chicken(♂) and kirin chicken(♀) were measured and the correlations between different traits were analyzed. The results showed that body length,keel length and shank length of male F1 hybrid offspring were significantly higher than those of female chickens(P 【 0. 05). The live weight,carcass weight,semi-eviscerated weight,semi-eviscerated ratio,eviscerated weight,chest muscle weight,the leg muscle weight and heart weight of male chickens were extremely significantly higher than that of female chickens(P 【 0. 01),and the leg muscle ratio and wings weight were significantly higher than that of female chickens(P 【 0. 05),but sebum thickness of male chickens was extremely significantly lower than that of female chickens(P 【 0. 01). Other indicators failed to reach the significant difference level. There were extremely significant or significant correlations between the slaughter performance and body size in F1 hybrid offspring. The regression equations between different indicators were identified and developed. The results provided a certain theoretical reference to predict slaughter performance indicators through a living body size measurement,and revealed an improved production performance of F1 hybrid offspring.展开更多
Gazetted in 1997, The TCMP (Tobago Cays Marine Park) is the only marine protected area within the territorial boundaries of St. Vincent and the Grenadines. Sea turtles are an important species in TCMP, and because t...Gazetted in 1997, The TCMP (Tobago Cays Marine Park) is the only marine protected area within the territorial boundaries of St. Vincent and the Grenadines. Sea turtles are an important species in TCMP, and because their globally endangered status have become the focus of an in-water monitoring program, primarily for green turtles (Chelonia mydas). Preliminary assessment indicated that the TCMP contains an important foraging aggregation of sub-adult green turtles. Since then two additional years of data has been collected; this data was analyzed to assess the health of the turtle population. The data also indicated that the weight was predictable according to carapace width and length and that the population is dominated by larger sub-adults.展开更多
Background During approximately 10,000 years of domestication and selection,a large number of structural variations(SVs)have emerged in the genome of pig breeds,profoundly influencing their phenotypes and the ability ...Background During approximately 10,000 years of domestication and selection,a large number of structural variations(SVs)have emerged in the genome of pig breeds,profoundly influencing their phenotypes and the ability to adapt to the local environment.SVs(≥50 bp)are widely distributed in the genome,mainly in the form of insertion(INS),mobile element insertion(MEI),deletion(DEL),duplication(DUP),inversion(INV),and translocation(TRA).While studies have investigated the SVs in pig genomes,genome-wide association studies(GWAS)-based on SVs have been rarely conducted.Results Here,we obtained a high-quality SV map containing 123,151 SVs from 15 Large White and 15 Min pigs through integrating the power of several SV tools,with 53.95%of the SVs being reported for the first time.These high-quality SVs were used to recover the population genetic structure,confirming the accuracy of genotyping.Potential functional SV loci were then identified based on positional effects and breed stratification.Finally,GWAS were performed for 36 traits by genotyping the screened potential causal loci in the F2 population according to their corresponding genomic positions.We identified a large number of loci involved in 8 carcass traits and 6 skeletal traits on chromosome 7,with FKBP5 containing the most significant SV locus for almost all traits.In addition,we found several significant loci in intramuscular fat,abdominal circumference,heart weight,and liver weight,etc.Conclusions We constructed a high-quality SV map using high-coverage sequencing data and then analyzed them by performing GWAS for 25 carcass traits,7 skeletal traits,and 4 meat quality traits to determine that SVs may affect body size between European and Chinese pig breeds.展开更多
It has been well known for many years that males of Luciola parvula (Coleoptera, Lampyridae) have two morphs, namely small and large morphs in Japan. This article performed a statistical reanalysis of their morphologi...It has been well known for many years that males of Luciola parvula (Coleoptera, Lampyridae) have two morphs, namely small and large morphs in Japan. This article performed a statistical reanalysis of their morphological measurements based on previously published data and compared them. As a result, the two morphs were found to have different allometric patterns in the Hakone and Nagano areas, Japan. In Hakone, the relationships between their pronotum width and length were expressed by a common allometric line and a shift in location along the line. However, in Nagano, the relationships between their pronotum width and body length were expressed by two parallel allometric lines (a common slope and different intercepts). The allometric pattern of males of this species may vary among different parts of the body or among different areas. Therefore, this article recommends future studies to measure the same parts of the body as previous studies to clarify geographic variation in allometric relationships.展开更多
Growth in arthropods in general and in insects in particular, is supposed to be discontinuous and occurs during moulting. In Culicidae in general and <i> <i><span style="font-family:Verdana;"&...Growth in arthropods in general and in insects in particular, is supposed to be discontinuous and occurs during moulting. In Culicidae in general and <i> <i><span style="font-family:Verdana;">Anopheles</span></i></i><span style="font-family:Verdana;"> in particular, the number of moults is five with the fourth which gives the pupae. It is known that moulting in insects is a genetic and physio</span><span><span style="font-family:Verdana;">logical phenomenon. Most physiological reactions are triggered by chemical or physical stimuli. The pressure exerted by the growth of the larval body on the exocuticle is one of the triggers of moulting. The objective of this work was therefore to determine the exact timing of the first three moults that determine the growth of <i></i></span><i><i><span style="font-family:Verdana;">An. gambiae</span></i></i></span><span style="font-family:Verdana;"> larvae from egg hatch to pupation to highlight the role of increased larval size in the stimulation of moulting. We therefore, undertook to rear larvae of this anopheline species</span><i> </i><span style="font-family:Verdana;">in the laboratory under conditions close to their natural environment from hatching to pupation. The length and width of the head, thorax and abdomen were recorded daily. Data analysis showed that the size of the head and thorax remained constant for the first three days (D0 to D2) of development and ab</span><span style="font-family:Verdana;">domen’s length for the first two days and then increased daily until day seven (D7) when it stopped. These observations led us to say that the M1 moult occurs at end of the third day of development and the M3 moult at end of the eighth day;the M2 moult could not be determined. All these observations led </span><span><span style="font-family:Verdana;">to the conclusion that the larval growth of <i> </i></span><i><i><span style="font-family:Verdana;">An. gambiae</span></i></i></span><span style="font-family:Verdana;"> has a continuous</span><span style="font-family:Verdana;"> regimen and the growth of the head and thorax of the larva plays a crucial role in the onset of moulting.</span>展开更多
[Objective] In the Xinjiang new era from October 2012 to February 2013, agricultural and animal husbandry Co. Ltd. feedlot Yining Tuogelake village used tethered and scattered feeding methods to conduct fattening youn...[Objective] In the Xinjiang new era from October 2012 to February 2013, agricultural and animal husbandry Co. Ltd. feedlot Yining Tuogelake village used tethered and scattered feeding methods to conduct fattening young Xinjiang brown cattle experiment. [Method] The 16-month-old young Xinjiang brown bulls were se- lected totaling 68 heads, divided into scattered group and tethered group. Male claves were taken as test subjects from October to February of following year and body conformation linear evaluation were made, followed by measurement of body size indexes and Regular collection of Blood samples. [Result] In the two feeding ways, scattered group feeding improved the ADG of youth Xinjiang brown cattle bull calf (P〈0.01), and the whole calf ADG 845.58g was significantly higher than that in tethered group at 619.11g, increasing by 36.58%; furthermore, scattered group in the December, January and February average daily weight gain was significantly higher compared with the tethered group at 13.61%, 32.32%, 53.47%, respectively. Scattered group feeding significantly increased the young calf serum phosphorus content (P〈0.01), higher than the tethered group at 0.62%, 7.89%, 14.29% in February, December and January respectively. But the tethered feeding young cattle serum phosphorus content gradually declined. Of the two groups, male calf serum calcium content had little effects on the serum calcium with insignificant difference (P〉0.05). Bulls by scattered feeding method was proved faster and better in the whole growth period, in terms of body height, body length, circumference, leg cir- cumference, rump length, waist high, sciatic wide, hip width basically in the contin- ued growth trend. [Conclusion] Scattered feeding can significantly improve the young Xinjiang brown cattle's daily gain, and accelerate the body height, heart girth and body length etc body growth. What's more, scattered feeding serum calcium and phosphorus content are significantly higher than tethered feeding.展开更多
This work is concerned with a kind of optimal control problem for a size-structured biological population model.Well-posedness of the state system and an adjoint system are proved by means of Banach's fixed point the...This work is concerned with a kind of optimal control problem for a size-structured biological population model.Well-posedness of the state system and an adjoint system are proved by means of Banach's fixed point theorem.Existence and uniqueness of optimal control are shown by functional analytical approach.Optimality conditions describing the optimal strategy are established via tangent and normal cones technique.The results are of the first ones for this novel structure.展开更多
基金supported by the grants from the National Natural Science Foundation of China(31071910 and 31200282)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘We acclimated adults of two viviparous (Phrynocephalus guinanens& and P. vlangalii) and one oviparous (P. versicolor) species of toad-headed lizards (Agamidae) to 28 ℃, 33 ℃ and 38 ℃ to examine whether thermal preference (preferred body temperature, Tp) and thermal tolerance (critical thermal minimum, CTMin; critical thermal maximum, CTMax) were affected by acclimation temperature, and correlate with body size and habitat use. Both Tp and CTMax were highest in P. versicolor and lowest in P. vlangalii, with P. guinanensis in between. The two viviparous species did not differ in CTMin and thermal tolerance range, and they both were more resistant to low temperatures and had a wider range of thermal tolerance than the oviparous species. Both CTMin and CTMax shifted upward as acclimation temperature increased in all the three species. Tp was higher in the lizards acclimated to 33 ℃ than in those to 28 ℃ or 38 ℃. The range of thermal tolerance was wider in the lizards acclimated to 28 ℃ than in those to 33 ℃ or 38 ℃. The data showed that: 1) thermal preference and tolerance were affected by acclimation temperature, and differed among the three species of Phrynocephalus lizards with different body sizes and habitat uses; 2) both Tp and CTMax were higher in the species exchanging heat more rapidly with the environment, and CTMin was higher in the species using warmer habitats during the active season; and 3) thermal preference and tolerance might correlat with body size and habitat use in Phrynocephalus lizards.
基金supported by the National Natural Science Foundation of China (32273136,31872572)Agriculture Research System of China (ARS-47)+1 种基金Science and Technology Planning Project of Guangdong Province (2023B1212060023)Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) (SML2023SP201)。
文摘Animal body size variation is of particular interest in evolutionary biology,but the genetic basis remains largely unknown.Previous studies have shown the presence of two parallel evolutionary genetic clusters within the fish genus Epinephelus with evident divergence in body size,providing an excellent opportunity to investigate the genetic basis of body size variation in vertebrates.Herein,we performed phylotranscriptomic analysis and reconstructed the phylogeny of 13 epinephelids originating from the South China Sea.Two genetic clades with an estimated divergence time of approximately 15.4 million years ago were correlated with large and small body size,respectively.A total of 180 rapidly evolving genes and two positively selected genes were identified between the two groups.Functional enrichment analyses of these candidate genes revealed distinct enrichment categories between the two groups.These pathways and genes may play important roles in body size variation in groupers through complex regulatory networks.Based on our results,we speculate that the ancestors of the two divergent groups of groupers may have adapted to different environments through habitat selection,leading to genetic variations in metabolic patterns,organ development,and lifespan,resulting in body size divergence between the two locally adapted populations.These findings provide important insights into the genetic mechanisms underlying body size variation in groupers and species differentiation.
基金Supported by Science and Technology Development of Hubei Province during the Eleventh Five-Year Plan Period (2006AA202A04)~~
文摘[Objective]The research aimed to study the polymorphism of intron 1 and its effects on prolactin(PRL) gene and body size traits of Jingjiang Partridge Duck.[Method]Taking 96 Jingjiang partridge ducks as materials,the polymorphism of intron 1 of PRL gene was detected by PCR-RFLP method.And the relationship between the gene polymorphism and body size traits was analyzed.[Result]Intron 1 in PRL gene of Jingjiang Partridge Duck had sequence polymorphism.Two kinds of genotypes(AB and BB) were detected by DraⅠrestriction and genotype BB was dominant in population(91.67%).The results of Chi-square test indicated that this site was in Hardy-Weinberg equilibrium in Jingjiang Duck(P 〉0.05).The results of least square analysis showed that the ducks with AB genotype had larger pelvis breadth(P 〈0.01) but smaller chest measurement(P 〈0.05) than those of BB ducks.[Conclusion]It was preliminarily concluded that PRL gene could be regarded as useful candidate gene(marker) for part of body size traits of Jingjiang Partridge Duck and part of body size traits can be improved by allele selection.
基金supported by the National Natural Science Foundation of China(3090014131270042)+1 种基金the Chinese Academy of Sciences(KSCX2-EW-J-22Y2C3011) to Jianguo CUI
文摘In anurans, the outcomes of male-male contests and female choice are often associated with body size. In some species, males evaluate an opponent’s fighting ability and females evaluate male quality on the basis of male communication signals, which are thought to reflect information concerning male body size. Nevertheless, previous studies reveal that male call structure is not always correlated with body size. In the present study we investigated the relationships between body size and call structure in the large treefrog, Rhacophorus dennysi, as well as the relationship of its calling behavior with air temperature and humidity. The results show that both the dominant and fundamental frequencies are negatively correlated with body size, while inter-note intervals are positively correlated with body size, indicating that call characters could reflect body size in this species.Additionally, calling in this tropical species exhibits a circadian rhythm insofar as relatively high temperature and low humidity during the day is associated with less vocal behavior. Thus, individual variations in call structure are mainly dependent on body size while the temporal rhythm of calling activity is affected by environmental conditions in large treefrogs.
文摘Arctodiaptomus salinus inhabits water bodies across Eurasia and North Africa. Based on our own data and that from the literature, we analyzed the influences of several factors on the intra- and inter-population variability of this species. A strong negative linear correlation between temperature and average body size in the Crimean and African populations was found, in which the parameters might be influenced by salinity. Meanwhile, a significant negative correlation between female body size and the altitude of habitats was found by comparing body size in populations from different regions. Individuals from environments with highly varying abiotic parameters, e.g. temporary reservoirs, had a larger body size than individuals from permanent water bodies. The changes in average body mass in populations were at 11.4 times, whereas, those in individual metabolic activities were at 6.2 times. Moreover, two size groups of A. salinus in the Crimean and the Siberian lakes were observed. The ratio of female length to male length fluctuated between 1.02 and 1.30. The average size of A. salinus in populations and its variations were determined by both genetic and environmental factors. However, the parities of these factors were unequal in either spatial or temporal scales.
基金Supported by the China Agriculture Research System(No.CARS-49)the National Natural Science Foundation of China(No.31772845)+1 种基金the Science and Technology Service Network Initiative of the Chinese Academy of Sciences(No.KFJ-STS-ZDTP-049)the Foundation of Zhejiang Key Laboratory of Exploitation and Preservation of Coastal Bio-Resource(No.J2018001)
文摘Gene expression variation can be considered as a phenotype,and it plays an important role in both acclimation and adaption.However,genetic variation of gene expression received much less attention than traditional commercial traits in aquaculture.To estimate the genetic variation and heritability of gene transcription in clam Meretrix petechialis,five Vibrio resistance-related genes were selected for gene expression analysis in the digestive gland,and an animal linear model was used to analyze data from quantitative real-time PCR(qRT-PCR).Among the five genes,BIRC7 showed significant additive genetic variations,the heritability of this gene of 12-month-and 15-month-old clams were 0.84±0.32 and 0.91±0.34,respectively.The heritability of other four genes(Bax,NFIL3,Big-Def,and CTL9)expression were low-tomoderate but not significantly expressed.Additionally,no significant phenotypic and genetic correlations between the BIRC7 transcription trait and body size were detected.This study highlights that certain gene expression variation is heritable and provides a reference for indirect selection of M.petechialis with high Vibrio resistance.
基金the NNSF of China (No.40206001)the Key Laboratory of Mariculture of Ministry of Education,Ocean University of China (No.200404)
文摘A 21-d laboratory experiment was conducted to study, the phosphorus (P) utilization of two different diets by redlip mullet Liza haematocheila T. & S. Sand-filtered water in salinity 30 and temperatare 25℃ was used. Twenty-nine fish individuals were divided into three groups: 11 to group 1 (G1) fed on diet 1, 11 to group 2 (G2) fed on diet 2, and 7 to contrast group. Diet 1 was a commercial feed, more valuable in nutrition than diet 2 that similar to natural detritus. The results show the intake phosphorus (IP) of G1 was significantly higher than that of G2, and both increased linearly with body size at a certain amount of diet. The retention phosphorus (RP) in fish of G1 was lower than G2. The relationship between retention phosphorus and body size was positive and stronger in G2. Significant difference in faecal phosphorus (FP) was found between G1 and G2. Body size significantly impacted the excretion phosphorus (EP) in G1 but G2. The loss of intake phosphorus in G1 was 10.83-20.27 mg per g fish weight gain, higher than that in G2 for 6.63-9.56. Of the phosphorus, about 10% was allocated into growth, 50% in faeces, and the rest lost in excretion. The main part of phosphorus was lost in faeces but excretion. The phosphorus budget of the fish could be described as 100IP = 7.40RP + 47.39FP + 36.63EP (Diet 1) or 100IP = 11.93RP + 56.64FP + 21.76EP (Diet 2).
基金the Sichuan Province Outstanding Youth Academic Technology Leaders Program(2013JQ0016)the Students Science and Technology Innovation Fund of China(201510638016)+1 种基金Sichuan Province Department of Education Innovation Team Project(14TD001515TD0019) for providing for financial support
文摘In anurans, body size and age of individuals generally affect male mating success. To test whether body size and age have effects on male mating success in the foam-nesting treefrog Polypedates megacephalus, a species widely distributed in China, we analyzed differences in body size and age between mated and unmated males for three populations using a Generalized Linear Mixed Model(GLMM). The results showed that mated males did not exhibit larger body size and older age than unmated males, suggesting that large and/or old male individuals did not have greater mating success than small and/or young males. Moreover, we also found a non-significant size-assortative mating pattern for all populations. Our findings suggest that body size and age of the foam-nesting treefrog do not affect male mating success.
基金funded by the National Key Research and Development Program of China(No.2019YFD0901000)the National Natural Science Foundation of China(No.31872575)the Key Research and Development Program of Shandong Province(No.2021SFGC0701).
文摘This study was performed to evaluate the effect of temperature on the carbon(C),nitrogen(N),and phosphorus(P)nu-trient budgets of adult steelhead trout(Oncorhynchus mykiss)with different body sizes.A complete two-factor experiment was con-ducted at four temperatures,i.e.,9(T9),13(T13),16(T1℃℃℃6),and 19(T19);and three body sizes,℃i.e.,0.65 kg±0.02 kg(S1),1.22 kg±0.06 kg(S2),and 2.05 kg±0.09 kg(S3).The following properties of steelhead trout were determined:C,N,and P nutrient budgets;feed intake rate;fecal production rate;oxygen consumption rate;ammonia excretion rate;phosphorus excretion rate;scope of the growth of C,N,and P;and absorption efficiency of C,N,and P.Results showed no significant interaction between temperature and body size in terms of the nutrient budgets of steelhead trout.However,temperature and body size played important separate roles in the nutrient budgets except for the absorption efficiency of nitrogen.The feed intake rate,fecal production rate,ammonia excretion rate,phosphorus excretion rate,and scope of the growth of C,N,and P were the highest in the T16 treatments.The absorption effi-ciency of C and P decreased as temperature increased.Nonlinear multiple regression results indicated that 15 was the approximate℃optimal temperature for the feeding and growth of steelhead trout.The feed intake rate,fecal production rate,oxygen consumption rate,ammonia excretion rate,phosphorus excretion rate,and scope of the growth of C,N,and P per unit of the body weight of fish decreased as body size increased.The absorption efficiency of C increased as body weight increased,and the absorption efficiencies of P in the S2 and S3 treatments were significantly higher than those in the S1 treatment.During the culture of steelhead trout,the daily ratio should be adjusted with changes in the temperature and body size of fish.Furthermore,managers should focus on the risk of hypoxia at high water temperatures.
基金a grant from the Chinese Natural Science Foundation to Fang ZHANG(NSFC grants 3187223031640073)Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources(No.591601)。
文摘Nonlinear phenomena are commonly shown in the vocalization of animals and exerts different adaptive functions.Although some studies have pointed out that nonlinear phenomena can enhance the individual identification of male Odorrana tormota,whether the nonlinear phenomena play a specific role in the sexual selection of O.tormota remain unclear.Here we presented evidence that there was a significant negative correlation(Pearson:n=30,r=0.65,P<0.001)between the nonlinear phenomena content and snout-vent length in the male O.tormota,and two-choice amplexus experiments showed that female O.tormota preferred male with smaller body size containing higher nonlinear phenomena content in its calls.Phonotaxis experiments also revealed that females preferred calls with higher nonlinear phenomena content.Additionally,compared to the calls with lower nonlinear phenomena content and higher fundamental frequency,there was shorter response time in phonotactic behaviour of female induced by the calls with higher nonlinear phenomena content and lower fundamental frequency.We argue that the nonlinear phenomena content in the calls of male O.tormota can convey its body size information and may provide important clues for female frogs in darkened surroundings to identify males’body size during mate choice,meanwhile,higher nonlinear phenomena content in males’calls may increase the attractiveness of males to females.The results of this study provide confirmation that,for O.tormota,nonlinear phenomena have specific function in mate choice.
基金supported by the National Natural Science Foundation of China(Nos.3127056831572290)+1 种基金the Youth Innovation Promotion Association CAS(2015304)the Sichuan Province Distinguished Youth Fund(2014JQ0056)
文摘Variation in body size and sexual size dimorphism(SSD) can have important consequences for animal ecology, behavior, population dynamics and the evolution of life-history traits. Organisms are expected to be larger in colder climate(i.e., Bergmann's rule) and SSD varies with body size(i.e., Rensch's rule). However, the underlying mechanisms are still elusive. The plateau brown frog(Rana kukunoris), a medium-sized anuran species with femalebiased SSD, is endemic to the Qinghai-Tibetan Plateau(QTP). From 1797 m(Maoxiang'ping) to 3453 m(Heihe'qiao) in the eastern margin of the QTP, we surveyed 10 populations of R. kukunoris and collected phalanges and snout vent length(SVL) data for 258 adult individuals(199 males versus 59 females). Based on these data, we explored how body size and SSD varying along the altitudinal gradient and examined the corresponding effects of temperature. We found body size to be larger at higher altitude for males but not for females, with likely effects from the temperature on the variation in male body size. Sex differences in growth rates may be the main cause of the variation in SSD. Our results suggested that only males follow the Bergmann's rule and variation in SSD of R. kukunoris do not support the Rensch's rule and its inverse. Therefore, the variations of body size can be different between sexes and the applicability of both Bergmann's rule and Rensch's rule should depend on species and environment where they live.
基金Financial supports were provided by grants from Natural Science Foundation of China (31270571)Hainan Key Program of Science and Technology (ZDXM20110008)131 Talent Project of Hangzhou City
文摘Body size and female reproduction in the water adult females larger than 500 mm SVL and 32 adult males Ledong, Hainan under permit to our laboratory in Hainan monitor lizard (Varanus salvator) were studied. Forty-two larger than 400 mm SVL were donated by local people in in 2013 and 2014. The largest male and female measured 745 and 755 mm SVL, respectively. The mean SVL was greater in adult females than in adult males. Males had larger heads (head width) than females of the same SVL. The smallest reproductive female in our sample was 565 mm SVL. Females produced a single clutch of 17.1 (10-23) pliable-shelled eggs per breeding season stretching from mid-June and mid-September. Clutch size and clutch mass were all positively related to female SVL. However, there was no significant linear relationship between egg mass and female SVL. Larger females generally produced more eggs, and thus heavier clutches than did smaller ones. There was no significant linear relationship between relative clutch mass and female SVL. Phylogenetic generalized least squares (PGLS) analysis, accounting for phylogenetic relationships, showed that clutch size was positively correlated with mean maternal SVL in varanid lizards. PGLS analysis showed that phylogenetic relationships did not affect clutch (or/and egg) mass and the SVL although there were significant linear relationship between clutch (or/and egg) mass and mean maternal SVL. Therefore, we could draw some general conclusions about the body size and reproductive tactics in varanid lizards that larger females generally produced more eggs, larger eggs and thus heavier clutches than did smaller ones.
基金Supported by Natural Science Foundation of Shandong Province(No.ZR2015PC010)Fiscal Application of Agricultural Technology Innovation Project of Shandong Province+1 种基金Gluse TCM industry upgrate key technology research and developmentNational Standardization Project of Traditional Chinese Medicine(No.ZYBZH-Y-SD-31)
文摘[ Objective] The study was to explore whether the body size, sexual behavior of male donkey had certain correlation with reproductive traits. [ Method] The data of body weight, body size and sexual behavior of male donkey during production were collected, combining with the semen quality data of ejaculation volume, density, motility and frozen-thawed semen motility were conducted the statistical analysis. [ Results] ( 1 ) Single ejaculation volume had a positive correlation with body height (r = 0. 423, P = 0. 044) and penis circumference (r = 0. 495, P = 0. 043 ) , and total number of sperm per ejaculate had a positiw: correlation with body weight (r = 0. 444, P = 0. 036) and scrotal circumference (r = 0. 520, P = 0. 039) ; (2) Ejaculation volume was negatively correlated with mount times (r = -0. 159, P = 0. 035) and erection time (r = -0. 181, P = 0. 023), semen density was negatively correlated with mating time (r = - 0.211, P = 0.004), and total sperm count was negatively correlated with erection time (r = - 0. 159 , P = 0. 047). [Condusion ] The quality of semen had a certain correlation with body size, body weight and sexual behavior.
基金Supported by Fund Project for Transformation of Scientific and Technological Achievements(2012GB2E000341)Science and Technology Program of Guangdong Province(2012B020305008)
文摘In order to study the meat development value of princess chicken,the body size traits and slaughter performance of 12-week-old F1 hybrid offspring of princess chicken(♂) and kirin chicken(♀) were measured and the correlations between different traits were analyzed. The results showed that body length,keel length and shank length of male F1 hybrid offspring were significantly higher than those of female chickens(P 【 0. 05). The live weight,carcass weight,semi-eviscerated weight,semi-eviscerated ratio,eviscerated weight,chest muscle weight,the leg muscle weight and heart weight of male chickens were extremely significantly higher than that of female chickens(P 【 0. 01),and the leg muscle ratio and wings weight were significantly higher than that of female chickens(P 【 0. 05),but sebum thickness of male chickens was extremely significantly lower than that of female chickens(P 【 0. 01). Other indicators failed to reach the significant difference level. There were extremely significant or significant correlations between the slaughter performance and body size in F1 hybrid offspring. The regression equations between different indicators were identified and developed. The results provided a certain theoretical reference to predict slaughter performance indicators through a living body size measurement,and revealed an improved production performance of F1 hybrid offspring.
文摘Gazetted in 1997, The TCMP (Tobago Cays Marine Park) is the only marine protected area within the territorial boundaries of St. Vincent and the Grenadines. Sea turtles are an important species in TCMP, and because their globally endangered status have become the focus of an in-water monitoring program, primarily for green turtles (Chelonia mydas). Preliminary assessment indicated that the TCMP contains an important foraging aggregation of sub-adult green turtles. Since then two additional years of data has been collected; this data was analyzed to assess the health of the turtle population. The data also indicated that the weight was predictable according to carapace width and length and that the population is dominated by larger sub-adults.
基金supported by the National Key R&D Program of China(2021YFD1301101)National Swine Industry Technology System(CARS-35)Agricultural Science and Technology Innovation Program(ASTIP-IAS02)。
文摘Background During approximately 10,000 years of domestication and selection,a large number of structural variations(SVs)have emerged in the genome of pig breeds,profoundly influencing their phenotypes and the ability to adapt to the local environment.SVs(≥50 bp)are widely distributed in the genome,mainly in the form of insertion(INS),mobile element insertion(MEI),deletion(DEL),duplication(DUP),inversion(INV),and translocation(TRA).While studies have investigated the SVs in pig genomes,genome-wide association studies(GWAS)-based on SVs have been rarely conducted.Results Here,we obtained a high-quality SV map containing 123,151 SVs from 15 Large White and 15 Min pigs through integrating the power of several SV tools,with 53.95%of the SVs being reported for the first time.These high-quality SVs were used to recover the population genetic structure,confirming the accuracy of genotyping.Potential functional SV loci were then identified based on positional effects and breed stratification.Finally,GWAS were performed for 36 traits by genotyping the screened potential causal loci in the F2 population according to their corresponding genomic positions.We identified a large number of loci involved in 8 carcass traits and 6 skeletal traits on chromosome 7,with FKBP5 containing the most significant SV locus for almost all traits.In addition,we found several significant loci in intramuscular fat,abdominal circumference,heart weight,and liver weight,etc.Conclusions We constructed a high-quality SV map using high-coverage sequencing data and then analyzed them by performing GWAS for 25 carcass traits,7 skeletal traits,and 4 meat quality traits to determine that SVs may affect body size between European and Chinese pig breeds.
文摘It has been well known for many years that males of Luciola parvula (Coleoptera, Lampyridae) have two morphs, namely small and large morphs in Japan. This article performed a statistical reanalysis of their morphological measurements based on previously published data and compared them. As a result, the two morphs were found to have different allometric patterns in the Hakone and Nagano areas, Japan. In Hakone, the relationships between their pronotum width and length were expressed by a common allometric line and a shift in location along the line. However, in Nagano, the relationships between their pronotum width and body length were expressed by two parallel allometric lines (a common slope and different intercepts). The allometric pattern of males of this species may vary among different parts of the body or among different areas. Therefore, this article recommends future studies to measure the same parts of the body as previous studies to clarify geographic variation in allometric relationships.
文摘Growth in arthropods in general and in insects in particular, is supposed to be discontinuous and occurs during moulting. In Culicidae in general and <i> <i><span style="font-family:Verdana;">Anopheles</span></i></i><span style="font-family:Verdana;"> in particular, the number of moults is five with the fourth which gives the pupae. It is known that moulting in insects is a genetic and physio</span><span><span style="font-family:Verdana;">logical phenomenon. Most physiological reactions are triggered by chemical or physical stimuli. The pressure exerted by the growth of the larval body on the exocuticle is one of the triggers of moulting. The objective of this work was therefore to determine the exact timing of the first three moults that determine the growth of <i></i></span><i><i><span style="font-family:Verdana;">An. gambiae</span></i></i></span><span style="font-family:Verdana;"> larvae from egg hatch to pupation to highlight the role of increased larval size in the stimulation of moulting. We therefore, undertook to rear larvae of this anopheline species</span><i> </i><span style="font-family:Verdana;">in the laboratory under conditions close to their natural environment from hatching to pupation. The length and width of the head, thorax and abdomen were recorded daily. Data analysis showed that the size of the head and thorax remained constant for the first three days (D0 to D2) of development and ab</span><span style="font-family:Verdana;">domen’s length for the first two days and then increased daily until day seven (D7) when it stopped. These observations led us to say that the M1 moult occurs at end of the third day of development and the M3 moult at end of the eighth day;the M2 moult could not be determined. All these observations led </span><span><span style="font-family:Verdana;">to the conclusion that the larval growth of <i> </i></span><i><i><span style="font-family:Verdana;">An. gambiae</span></i></i></span><span style="font-family:Verdana;"> has a continuous</span><span style="font-family:Verdana;"> regimen and the growth of the head and thorax of the larva plays a crucial role in the onset of moulting.</span>
基金Supported by the NationalTechnology Support Program(2011BAD47B02)~~
文摘[Objective] In the Xinjiang new era from October 2012 to February 2013, agricultural and animal husbandry Co. Ltd. feedlot Yining Tuogelake village used tethered and scattered feeding methods to conduct fattening young Xinjiang brown cattle experiment. [Method] The 16-month-old young Xinjiang brown bulls were se- lected totaling 68 heads, divided into scattered group and tethered group. Male claves were taken as test subjects from October to February of following year and body conformation linear evaluation were made, followed by measurement of body size indexes and Regular collection of Blood samples. [Result] In the two feeding ways, scattered group feeding improved the ADG of youth Xinjiang brown cattle bull calf (P〈0.01), and the whole calf ADG 845.58g was significantly higher than that in tethered group at 619.11g, increasing by 36.58%; furthermore, scattered group in the December, January and February average daily weight gain was significantly higher compared with the tethered group at 13.61%, 32.32%, 53.47%, respectively. Scattered group feeding significantly increased the young calf serum phosphorus content (P〈0.01), higher than the tethered group at 0.62%, 7.89%, 14.29% in February, December and January respectively. But the tethered feeding young cattle serum phosphorus content gradually declined. Of the two groups, male calf serum calcium content had little effects on the serum calcium with insignificant difference (P〉0.05). Bulls by scattered feeding method was proved faster and better in the whole growth period, in terms of body height, body length, circumference, leg cir- cumference, rump length, waist high, sciatic wide, hip width basically in the contin- ued growth trend. [Conclusion] Scattered feeding can significantly improve the young Xinjiang brown cattle's daily gain, and accelerate the body height, heart girth and body length etc body growth. What's more, scattered feeding serum calcium and phosphorus content are significantly higher than tethered feeding.
基金Supported by the ZPNSFC (LY12A01023)the National Natural Science Foundation of China (11271104,11061017)
文摘This work is concerned with a kind of optimal control problem for a size-structured biological population model.Well-posedness of the state system and an adjoint system are proved by means of Banach's fixed point theorem.Existence and uniqueness of optimal control are shown by functional analytical approach.Optimality conditions describing the optimal strategy are established via tangent and normal cones technique.The results are of the first ones for this novel structure.