Effects of Astragalus Powder on Serum Lipid and Body Fat Content of Fast Large-scale Quality Chickens

[ Objective] To study the effects of astragalus powder on serum lipids and body fat contents of fast large-scale quality chickens, and thus provide a theoretical basis for its application in poultry production,[ Method ] All the 180 1-day-old healthy Liangfeng chickens were randomly divided into six groups. Group 1 was the control group, fed with basal diet; group 2, group 3 and group 4 were fed with basal diet added with 0.75%, 1.0% and 1.25% astragalus powder, respectively; group 5 and group 6 were separately fed with basal diet added with 1.0% and 1.25% astragalus pow- der, but the astragalus powder was used for 10 d and then was forbidden for 10 d in turn during the whole experiment. The content of triglyceride （TG）, total cholesterol （TCHO）, high-density lipoprotein-Cholesterol （ HDL-C）, and low-density lipoprotein-Cholesterol （LDL-C） were respectively determined when the chickens were 35-day-old and 63-day-old, while the percentage of abdominal fat （PAF） as well as intramuscular fat （IMF） and subcutaneous fat ply （SFP） was measured when the chickens were 63-day-old. [ Result] In 35-day-old chickens, the levels of TCHO were sig- nificantly or very significantly lower in group 3, group 4, and group 6 than in control group （ P 〈0.05 or 0.01 ） ; the levels of LDL-C significantly lower in group 3 and group 6 （ P〈0. 05） ; the level of HDL-C significantly higher in group 5 （P〈0.05）. In 63-day-old chickens, the levels of TCHO and LDL-C were significantly or very significantly lower in group 3, group 4, and group 5 than in control group （ P 〈 0.05 or 0.01 ） while the levels of HDL-C were significantly higher in these groups; the PAF was significantly lower in group 3 （ P 〈 0.05）. [ Condasion] Astragalus powder should re- duce the levels of TG, TCHO and LDL-C, promote HDL-C content, and also play a certain regulative role in deposition of abdominal fat.

Observation on Activities of Air Sac in Opened Body Cavity of Chicken

The body cavity of chicken under anesthesia was opened, and then the state of breathing and activities of air sac wal were observed. The results showed that, although the body cavity was opened, the chicken could stil breathe. When the chicken breathed in, the chest sidewal , thoracico-abdominal diaphragm and lung diaphragm al initiatively became larger, inflating the prethoracic and metathoracic air sacs; the cervical, clavicular and abdominal air sac wal s al contracted, shrinking the air sacs. When the chicken breathed out, the chest sidewal , thoracico-ab-dominal diaphragm and lung diaphragm initiatively contracted, shrinking the pretho-racic and metathoracic air sacs; the cervical, clavicular and abdominal air sac wal s al expanded, expanding the air sacs. Therefore, the chicken could stil breathe after the body cavity was opened. When the chicken breathed in, the prethoracic and metathoracic air sacs were al expanded, and the air flowed from the cervical, clav-icular and abdominal air sacs and respiratory tract to the prethoracic and metatho-racic air sacs through the lung, shrinking the cervical, clavicular and abdominal air sacs; when the chicken breathed out, the prethoracic and metathoracic air sacs wal s al contracted, and the air was extruded from the prethoracic and metathoracic air sacs into the cervical, clavicular and abdominal air sacs and respiratory tract trough the lung, expanding the cervical, clavicular and abdominal air sacs. During the entire breathing process, the prethoracic and metathoracic air sacs al can ex-pand and shrink initiatively, making the air flow though the lung.

Age and Gender Dependent Nutrient Composition of Feather and Feather-Free Body Fractions in Meat-Type Chickens

The objective of this research was to update current results about the nutrient composition of broiler chickens during the growth period up to market age. Two growth experiments were conducted for assessing the nutrient content of feathers and feather-free body of meat-type chickens (Ross 308). Both male and female birds were reared under uniform management conditions (floor pens;15 pens per gender;5 birds per pen). Experimental diets both for the starter (day 1 to 22) and the grower period (day 22 to 36) were based on corn, wheat, soybean meal, soybean protein concentrate and well balanced with feed amino acids. The feed protein quality was adapted to the ideal amino acid ratio and equated within both of the feeding periods by adjusting a constant mixture of the feed proteins. Each 15 birds per gender (3 pens of 5 birds) were selected and subsequently fasted for 24 h before quantitative de-feathering both at start of the experiment and further on weekly up to the end of the 5th week. Nutrient content was determined in representative samples of the feather and feather-free body fraction. In the feather dry matter (DM) very high crude protein (CP) concentrations (>96%) with low age-dependent and insignificant gender-specific differences were observed. In spite, a relatively high variation of CP content in the DM of feather-free body was found. Depending on age, the body CP significantly decreased with increasing age, but male birds yielded higher (p < 0.001) CP content. The crude lipid content of the feather-free and whole empty body significantly increased with age and was higher in female as compared to male birds (p < 0.001). Depending on age and gender, the crude ash content both in feathers and feather-free body of modern fast-growing chickens was rather low and with very low variation.

Age and Gender Dependent Amino Acid Concentrations in the Feather, Feather-Free and Whole Empty Body Protein of Fast Growing Meat-Type Chickens

Two consecutive growth experiments with meat-type chickens (Ross 308) were conducted in order to quantify the age-dependent amino acid (AA) content in the whole body protein of male and female birds based on experimental data of the feather and feather-free body protein fractions. Birds were reared under uniform housing and feeding conditions (floor pens, 15 pens per gender, 5 birds per pen) during the starter (day 1 to 22) and grower period (day 22 to 36). Both the starter and grower diet based on corn, wheat, soybean meal, soybean protein concentrate and feed amino acids was formulated to ensure an equal feed protein quality close to the ideal amino acid ratio by adjusting a constant mixture of the feed proteins. At start of the experiment and further on weekly up to the end of the 5th week, 15 birds per gender (each 3 pens of 5 birds) were selected and fasted for 24 h, to emptying of gastro-intestinal tract, respectively. Subsequently, birds were euthanized and the feathers were manually removed. Nitrogen (N) and AA content were determined both in the feather and feather-free body fraction. The concentration of individual AAs in both of body protein fraction is varying considerably. Explicitly higher Cys, Ser and Pro but importantly lower Met, Lys and His concentrations were found in the feather protein. Furthermore, significant differences (p for nearly all AAs of the studied body protein fractions and the whole empty body protein dependent on age of birds were observed. Especially high deviations were obtained during the first week of age and at the end of the experiment. According to this observed variation of AA concentrations must be concluded that the body AA composition of meat-type chickens during growth is not constant. The detected gender-specific differences for several AAs in the feather and body protein of male and female birds were rather low and with very low variation.

The Change of Plasm a very Low Density Lipoprotein Concentration Pre-or Post-Feeding and in Conrrelation with Body Fatness Traits in Broiler Chickens

Blood samples were taken from birds,from a commercial line of broiler chicken,being in a fully fed state and in fasting state for 2,4,6 hours respectively at 49 d of age and plasma very low density lipoprotein(VLDL) concentration was measured with turbidimetric assay.The experiment results showed that the variation coefficients of plasma VLDL concentration mersured at four different times were 58.11%,74.39%,69.70%,47.83%,respectively for male broilers,and 41.82%,60.87%.59.26%,50.0%for female broilers respectively.Plasma VLDL concentration decreased with the fasting time.There was a significant positive phenotypic correlation between abdominal fat weight,percentage of abdominal fat and plasma VLDL concentration for the birds being in fully feeding state,and the correlation decreased or no longer existed for the bired being in fasting state.The conclusion was that for practically application of plasma VLDL content selected in broiler chicken breeding,blood samples should be collected from birds being in feeding state.

Correlation Analysis between Body Size and Slaughter Performance in F-_1 Hybrid Offspring of Princess Chicken and Kirin Chicken

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.

Age and Gender Depending Growth of Feathers and Feather-Free Body in Modern Fast Growing Meat-Type Chickens

Two growth experiments with fast growing meat type chickens (Ross 308) were conducted to assess the growth of feathers and feather-free body dependent on age and gender (male:female ratio = 1:1). Birds were reared under uniform management and feeding conditions (floor pens;15 pens per gender;5 birds per pen) during the starter (day 1 to 22) and grower period (day 22 to 36). Diets were based on corn, wheat, soybean meal, soybean protein concentrate and balanced with feed amino acids to ensure an equal feed protein quality close to the ideal amino acid ratio by a constant mixture of the feed proteins. At start of the experiment and further on weekly up to the end of the 5th week, 15 birds per gender (each 3 pens of 5 birds) were selected and 24 h fasted before quantitative de-feathering. Both feather and feather free body fractions were significantly increased with increasing age of the birds (p < 0.001). Feather percentage as related to the empty body weight increased non-linearly from approximately 2% at the end of the first week to about 4% at the end of the experiment. Feather percentage and dry matter content of the feather-free body was significantly higher in female birds (p < 0.001) as compared to males. Further investigations will show how this varying proportions impact on nutrient deposition of modern meat-type chickens dependent on age and gender, respectively.

Effect of dietary energy level on body weight, testicular development and semen quality of local barred chicken of the western highlands of Cameroon

This study was designed to examine the effects of dietary energy levels on some growth and reproductive parameters of local barred chickens in Cameroon. For this purpose, One hundred and forty four day-old barred male chicks, weighing 28.33 g in average were randomly divided into 12 groups of 12 chicks each. Three feeding programs (FP) comprising each a starter diet from day old to 12 weeks (S0: 2800 Kcal/Kg;S1: 2900 Kcal/Kg;S2: 3000 Kcal/Kg) and grower diet from 13 to 20 weeks (G0: 2900 Kcal/Kg;G1: 3000 Kcal/ Kg;G2: 3100 Kcal/Kg) were used and designated FP1, FP2 and FP3 respectively. Each of the FP was randomly allotted of 4 groups of 12 birds in a completely randomized design. Throughout experiment (1 day old to 20 weeks), body weight was recovered every 2 weeks. At 20 weeks of age, roosters were sacrificed;semen characteristic was analyzed and testes were characterized. Between 2 to 10 weeks old, body weight of cocks fed with FP3 was significantly higher (P < 0.05) as compared to others FP. Inversely, from 12 to 20 weeks, body weight of cocks receiving FP1 was significantly higher (P < 0.05) than that of cocks receiving feeding programs 2 and 3. At 20 weeks, 100% of cocks fed on FP3 produced semen versus 66.66% and 16.66% respectively for those on FP1 and FP2. Semen volume and mass motility of cocks fed on FP3 or FP1 were significantly (P < 0.05) higher than FP2. It was concluded that FP1 had more suitable dietary energy levels for growth and reproduction of local barred cocks.

Factors Influencing the Morphological Characteristics of Village Chickens’ Genetic Resources in the Abu-Dhabi Emirate, UAE

The study was accomplished to identify the characteristics of village chickens’ (VCs) genetic resources in the Abu-Dhabi Emirate of United Arab Emirate (UAE) and to study factors affecting these characteristics. Each bird was individually observed, identified, measured and characterized of thirteen VCs pure breeds and crossbreds. The overall VCs had normal feather morphology (95.1%) and distribution (77%). Except for Fayomi chickens which were 100% mottled, no specific plumage pattern was found. Almost 52% of the VCs had white skins. Six different colors were reported for the shanks and maximized for white shanks (34.3%). Large breasts (46%) were more available. The predominant plumage color was mixed colors (37.5%). Face size tended to be small (42.8%) to medium (40.4%). More brown (48.9%) then orange (27.3%) eyes were found. Dark (49.7%) beaks were more available than white (28.6%) or yellow (21.7%) beaks. The distribution of wattle colors was similar to that of ear-lob colors with some variation. Small wattles (41.9%) were most available. Single comb (82.4%) is the most available;11 other types and one with no comb were represented with low frequencies. In the whole sample, red and white combs (56.7%) were the most available;however, plain red (23.8%) and red and black (15.5%) were represented. Results of factors influence showed that body weight was high significantly (P < 0.01) influenced by the interaction between both breed and region and breed and sex. Significant (P < 0.01) influence of interaction was observed between breed and location on body length, wing span and shank length. The interaction between breed and sex only significantly (P < 0.01) influenced shank length. Though, all main effects of breed, sex and region significantly (P < 0.01) influenced continuous measures. Most morphological characteristics were significantly (P < 0.01) different among breeds. This study reported the morphological characteristics of the different VCs breeds kept in Abu-Dhabi Emirate, which considered the scientific base for future implementing of conservation and/or genetic improvement programs.

Age and Gender Dependent Deposition of Crude Nutrients and Energy in Fast Growing Meat-Type Chickens

Two consecutive growth studies were conducted to investigate the age-dependent nutrient and energy deposition in male and female meat-type chickens (Ross 308) based on feather and feather-free body fraction data determined according to the comparative slaughter technique. Birds were reared under standardized housing conditions (15 floor pens per gender, 5 birds per pen). Both the starter (day 1 to 22) and grower diets (day 22 to 36) were based on corn, wheat, soybean meal, soybean protein concentrate and crystalline feed amino acids. Diets were formulated to ensure an equal feed protein quality close to the ideal amino acid ratio by adjusting a constant mixture of the feed proteins. Individual body weight (BW) and feed intake per pen were recorded weekly. At the start (day 1) as well as on a weekly basis until the end of the 5th week, 15 birds per gender (each 3 pens of 5 birds) were selected and euthanized following 24 h feed deprivation. Subsequently, the feathers were manually removed and quantified. Crude nutrient analysed in representative samples of both feather and feather-free body fractions. The nutrient and energy deposition in the bodies of both genders were significantly increased with increasing age (p . Male birds deposited significantly higher body protein (p and female birds significantly more fat and energy in the whole body (p during the entire growth period. In contrast, no differences were found in protein contents of the BW gain between genders dependent on age (p > 0.05). However, the protein partitioning in the gain of both analyzed body fractions provided oppositional results. Accordingly, male birds yielded relatively more protein in the feather-free body fraction (p and females relatively more feather protein (p as related to the whole body protein gain.

Effects of the Partial Replacement of Soybean Meal by Insect or Algae Meal in Chicken Diets with Graded Amino Acid Supply on Parameters of Gut Microbiology and Dietary Protein Quality

Insects or algae are considered future solutions to substitute imported feed proteins like soybean meal (SBM) in animal nutrition. The objective of this research, as part of the multidisciplinary project “Sustainability transitions”, focused on replacing 50% SBM by partly defatted larvae meal from black soldier flies (Hermetia illucens) or the blue-green algae Spirulina platensis in meat type chicken diets. The current study aimed to evaluate the effects on body composition, protein quality, apparent precaecal digestibility (apcD) and parameters of intestinal microbiota. In total, 288 one-day-old male growing chickens (Ross 308) from a commercial hatchery were randomly allotted to 48 pens (6 birds per pen) across five diets, which were fed at a free choice level. The control diet utilized SBM, wheat and corn as main ingredients, and experimental diets replaced 50% of SBM by the alternative proteins under study. Amino acid (AA) supplementation of the final diets was conducted both at a basic level (diets HM, SM;Lys and Met added equal to the control diet) and an extended level of AA fortification (diets HM+, SM+;extended supplementation of Lys, Met, Thr, Arg). After finishing the growth study, 4 individual birds per diet were slaughtered for whole body analyses to derive nutrient utilization and dietary protein quality parameters. Additionally, pooled chyme samples from 16 birds per diet (control, HM and SM) were analyzed to assess apcD and microbial parameters. Diets HM and SM with a basic level of AA fortification led to significant depressions in nutrient deposition and dietary protein quality. However, HM+ and SM+ diets with an extended level of AA supplementation led to significantly improved responses;however these were still generally not on par with the control diet. The HM+ diet provided superior CP deposition and dietary protein quality, as compared to the SM+ diet, but equal to the control diet. Results of gut microbiology yielded no significant effects due to feeding the alternative protein sources under study.

Study on Anti-infection Effect of Polysaccharide from Agaricus blazei Murrill on Chickens

In order to study the anti-bacterial infection effect of polysaccharide from Agaricus blazei Murrill on chickens, the experimental groups were orally administrated A. blazei polysaccharide at low dose and high dose, respectively, for 14 d continuously, and then, the chickens in various groups were infected with Escherichia coli or Pasteurella pneumotropica , so as to observe the clinical symptoms of chickens and record the change in body weight. Anatomy was performed 14 d later, and the organ indices were determined, so as to study the anti-bacterial infection effect of A. blazei polysaccharide on chickens. The results showed that after bacterial infection, the high-dose A. blazei polysaccharide group was significantly differed from other groups in changes of body weight and organ indices. It indicates that oral administration of high concentration of A. blazei polysaccharide could promote the development of poultry organs, thereby improving the immunity of organisms.

Long-Term Impacts of Cover Crops, Chicken Litter, and Crop Rotations on Soil Health in No-Till Systems

Identification of management practices that can improve soil health is critical to improving the sustainability of soybean [Glycine max (L.) Merr.] production. The objective of this study was to examine the long-term effects of continuous soybean, corn-soybean, and soybean-cotton rotations with chicken litter and cover crops (hairy vetch, wheat, fallow) on soil health parameters, including nutrient accumulation and soil organic matter dynamics under a split plot design. The depth intervals of soil sampling were 0 - 15, 15 - 30, 30 - 60, and 60 - 90 cm. Chicken litter resulted in 62.1% and 32.8% higher water extractable organic soil N content than fallow and wheat, respectively, in the surface 0 - 15 cm of soil only. However, there was no significant difference in 1-day Solvita respiration, water extractable organic C, C/N ratio, health score, moisture, earthworm, organic matter, pH, or CEC of soil among fallow, hairy vetch, chicken litter, and wheat regardless of soil depth. Unexpectedly, annual application of chicken litter at 4.4 Mg ha−1 as an N source or growing a winter-season cover crop such as hairy vetch or wheat for continuous 16 years did not significantly increase soil organic matter or water extractable organic soil C. Annual application of chicken litter at 4.4 metric tons (Mg) ha–1 for 16 years increased soil nitrate-nitrogen (NO3−-N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), copper (Cu), and zinc (Zn) contents by 92%, 400%, 134%, 20%, 43%, 206%, and 430% in 0 - 15 cm depth compared with their initial soil values, respectively, extracted with Haney H3A-2 (2 g L–1 lithium citrate + 0.6 g L–1 citric acid + 0.4 g L–1 malic acid + 0.4 g L–1 oxalic acid) solution. The increases enhanced soil supply of these nutrients to following crops, but also increased the risks of losing them to the environment. Hairy vetch caused higher H3A extracted soil manganese (Mn) content than fallow and chicken litter in 0 - 60 cm. There was no significant difference in 1-day Solvita respiration, water extractable organic C and N, health score, moisture, organic matter, pH, CEC, or population of earthworm of soil among continuous soybean, corn-soybean, and soybean-cotton in any soil depth. Another major finding of this study was that continuous soybean exerted no adverse effect on soil health relative to the commonly used corn (Zea mays L.)-soybean and soybean-cotton (Gossypium hirsutum L.) rotations under no-tillage after 16 years. To mitigate the risks of nutrient runoff and leaching from long-term chicken litter application, we recommend reducing litter application rates and integrating cover crops into crop rotations to enhance nutrient cycling and reduce environmental impacts.

Production Performance of Different Generations of Muchuan Blackbone Chicken

In order to formulate feasible conservation measures and develop and utilize Muchuan black-bone chicken rationally,two generations of Muchuan black-bone chicken were bred,and their production performance and slaughter traits( at the age of 300 d) were compared. The results showed that the reproductive performance,slaughter performance and body size of the Muchuan black-bone chicken of Generation 1( G_1)were all improved compared with those of the Generation 0( G_0)( P <0. 05). At the age of 300 d,the live weight,carcass weight,and leg muscle weight of the G_1 were significantly higher than those of the G_0( P <0. 05); and the chest width of the cocks of the G_1 was significantly higher than that of the G_0( P <0. 05). It suggests that after rigorous selection and utilization of modern poultry breeding techniques,the reproductive performance,slaughter performance and survival rate of Muchuan black-bone chicken can be improved significantly.

藏鸡杂交组合生长发育规律研究

研究旨在通过藏鸡杂交分析其生长发育规律,为藏鸡的杂交利用打好理论基础。以藏鸡纯系及其他2个地方鸡培育品系为素材,组成3个二元杂交组合和2个纯系组合,观测育雏期体重、公鸡7~13周龄体重、母鸡7~44周龄体重和13周龄公母鸡体尺、44周龄母鸡体尺,分析体重体尺相关性,探明藏鸡杂交鸡生长发育规律。结果显示:杂交组合各阶段公母鸡体重均明显大于藏鸡纯系(P<0.05),13周龄公母鸡体尺、44周龄母鸡体尺也明显大于藏鸡纯系(P<0.05)。各杂交组合公鸡体重体尺相关性较高,而母鸡则较低,综合分析表明,含藏鸡血缘的杂交鸡体重、体尺性状与藏鸡纯系相比均显著提高(P<0.05),其生长性能具有明显杂交优势。

温岭草鸡体尺和屠宰性能测定及相关性分析

温岭草鸡是浙江省优质地方品种,具有肉质好、口感佳等特点。本研究随机选择300日龄温岭草鸡公母各15只,进行体尺和屠宰性能测定并作相关性分析。结果显示,温岭草鸡胸深较大,体形紧凑,屠宰性能较好。胫围与屠宰指标相关程度高,除腹脂质量外,体尺与屠宰指标间均存在显著相关。

贵州地方鸡种体重生长曲线的拟合分析

为探究贵州省赤水乌骨鸡、黔东南小香鸡、乌蒙乌骨鸡、威宁鸡和贵州黄鸡这5个地方鸡种生长发育规律,采用Logistic、Gompertz和von Bertalanffy 3种非线性模型对5个地方鸡种的生长曲线进行拟合,选取5个品种鸡各60只,公母各30只,测定0、2、4、6、8、10、12、14、16、18周龄时的体重。结果:5个品种鸡的生长趋势一致,3个模型均能较好地拟合5个品种鸡的生长变化情况,拟合度均在0.98以上,其中von Bertalanffy模型对5个品种鸡的生长曲线拟合效果最好;同时期的鸡体重以贵州黄鸡最重,黔东南小香鸡最轻,赤水乌骨鸡、乌蒙乌骨鸡和威宁鸡相近;5个品种鸡的拐点周龄分别为9.2、7.9、7.3、8.9和8.4,拐点体重分别为870.71、509.18、708.29、834.35和945.52 g。通过拟合的生长曲线模型对鸡体重进行评估,可为贵州省地方鸡的科学饲养、品种资源利用及选育提供依据。

8个地方鸡品种的体尺、屠宰性能及肉品质的比较及综合评价

【目的】通过比较分析贵州省8个地方鸡品种的体尺、屠宰性能及肉品质性状差异,为贵州地方鸡种的保护开发和利用提供基础数据。【方法】采用常规方法对乌蒙乌骨鸡、威宁鸡、普定高脚鸡、兴义矮脚鸡、黔东南小香鸡、赤水乌骨鸡、长顺绿壳蛋鸡和瑶山鸡的体尺指标、屠宰性能和肉品质性状指标进行测定,利用主成分分析法构建肉用性状综合评价模型。【结果】贵州8个地方鸡品种体尺性状、屠宰性能及肉品质指标存在明显差异,但屠宰率均大于86%,全净膛率均大于67%,8个品种均表现出了较佳的产肉性能;成功构建了肉用鸡综合评价模型,评分结果为:威宁鸡>乌蒙乌骨鸡>普定高脚鸡>赤水乌骨鸡>瑶山鸡>兴义矮脚鸡>黔东南小香鸡>长顺绿壳蛋鸡。【结论】8个地方鸡品种均表现出了良好的产肉性,是优质的肉鸡种质资源;综合评价结果显示,威宁鸡和乌蒙乌骨鸡肉用性能比较出色。

白背黄花稔环境和饲养方式对宁都黄鸡体尺、屠宰性能、肉品质以及血清生化指标的影响

【目的】旨在探究种植白背黄花稔(Sida rhombifolia L.)的散养环境和不同饲养方式对宁都黄鸡体尺性状、屠宰性能、肉品质以及血清生化指标的影响,为宁都黄鸡养殖模式选择和优化提供科学依据。【方法】选择180只72 d宁都黄鸡母鸡,随机分成3组:白背黄花稔种植环境散养组(SF组)100只、不含白背黄花稔环境散养组(NSF组)50只、笼养组(CK组)30只。两个散养组饲养密度相同。121 d时,每个组随机选取10只鸡测定体尺、屠宰性能、肉品质以及血清生化指标。【结果】(1)体尺性状方面,与NSF组相比,SF组体斜长、龙骨长、胸宽显著升高(P<0.05);CK组龙骨长、胸宽、胫长显著降低(P<0.05)。(2)屠宰性能与肉品质方面,较之NSF组,CK组半净膛率、全净膛率、胸肌率、肌胃指数、脾脏指数、肌束内肌纤维数量显著降低(P<0.05),宰前体重、屠体重、肝脏指数、腹脂率、卵巢指数、输卵管指数、肠长、胸肌pH值、肌束膜厚度显著升高(P<0.05);SF组肌胃指数显著降低(P<0.05)。(3)血清生化指标方面,较之NSF组,CK组白蛋白(ALB)显著降低(P<0.05),尿素氮(BUN)和谷丙转氨酶(ALTGPT)显著升高(P<0.05);SF组尿素氮(BUN)和肌酐(CRE)显著降低(P<0.05)。【结论】散养模式能促进宁都黄鸡体尺性状发育、提高屠宰性能和免疫器官发育,可显著降低肉质pH值,以及改善机体蛋白质代谢和肝脏代谢功能。白背黄花稔环境下散养可促进宁都黄鸡体尺发育,可减缓宁都黄鸡肾脏损伤。

固始鸡A系与矮小贵妃鸡杂交F_(1)代生长性能探究及生长曲线拟合

试验旨在探究固始鸡A系与矮小贵妃鸡杂交后代的生长发育规律,选育出最优杂交组合。试验以固始鸡A系和矮小贵妃鸡进行正反交后代为素材,每周测量体重,90日龄和110日龄分别测量体尺性状并进行相关性分析,使用Logistic、Gompertz和Von-Bertalanffy三种模型拟合其生长曲线。结果显示,前4周,AG公母鸡与GA公母鸡的生长速度差异不大,4周龄以后,生长速度出现差异分化,GA公鸡的拐点周龄为8周,AG公鸡的拐点周龄为7.2周。GA母鸡的拐点周龄为7.9周,AG母鸡的拐点周龄为6.7周。90日龄时,GA母鸡的体重、体斜长、胫长、胸深优于AG母鸡,110日龄时,GA公鸡的体斜长优于AG公鸡,与AG群体相比,GA群体体尺性状较为优良。GA群体体重与体斜长和骨盆宽存在显著相关(P<0.05)。Gompertz模型对AG公鸡与GA母鸡这两个群体拟合效果更佳,Logistic曲线对AG母鸡和GA公鸡这两个群体拟合效果更佳。综上所述,矮小贵妃鸡♂×固始鸡A系♀为最优杂交组合。