Allele-specific expression and splicing provide insight into the phenotypic differences between thin- and fat-tailed sheep breeds

The sheep(Ovis aries) was one of the first grazing animals to be domesticated approximately 11,000 years ago in the Fertile Crescent(Chessa et al., 2009). Since domestication, a wide variety of sheep breeds with different production traitsand morphological characteristics have been shaped under the influence of natural and artificial selection. According to the fat content in tail, sheep can be mainly classified into two groups: thin-and fat-tailed breeds.

Estimation of Fat-tail Weight by External Fat-tail Dimensions in Lori-Bakhtiari Sheep

In this study fat-tail weight was estimated by external fat-tail dimensions. External fat-tail dimensions included upper, middle and lower width, length, length of gap, depth, upper and middle circumference recorded on 1,482 head of Lori-Bakhtiari lambs at 6 months. Of these about 311 lambs were slaughtered at the age of six months. Prediction equations were derived for fat-tail weight by multiple regression analyses with two methods. The results showed that the measure of middle circumference fat-tail was as most important measure in estimation of fat-tail weight. The measure of middle circumference fat-tail accounted for 76 percent of variation in fat-tail weight. The regression equations for predicting fat-tail weight using external fat-tail dimensions obtained from stepwise regression procedure can be estimated only with using from the lower width, length, middle circumference fat-tail and body weight with high acc, uracy （0.92）. Average of fat-tail weight estimated in the age of six months in lambs was 2.39 kg. The highest regression coefficient of external fat-tail dimensions on fat-tail weight observed for the length of fat-tail （0.095 kg）. Results of the present investigation showed that fat-tail weight in live sheep of Lori-Bakhtiari, could be estimated by measuring external fat-tail dimensions.

Cervical dilation and improvement of reproductive performance in fat-tailed ewes via cervical dilator treatments

Objective:To determine the effect of different cervical dilators on cervical dilation and reproductive performance of fat-tailed ewes.Methods: In experiment 1140 ewes were divided into seven groups with seven different treatments as following: 10 mL normal saline (control group), 100 IU oxytocin (OT group), 100 μg estradiol and 100 IU oxytocin (E2+OT group), 5 mL relaxin (R group), 2 mL sensiblex (SEN group), 200 μg misoprostol (MIS group) or 200 μg dinoprostone (DIN group). In experiment 2, artificial insemination was applied for evaluation of reproductive performance in experimental groups.Results: In experiment 1, the highest cervical dilation was observed in OT (90%) and E2+OT (100%) groups (P<0.05), while no significant differences was found among DIN, MIS, SEN and R groups (80%, 75%, 70% and 65%, respectively). In addition, the lowest cervical dilation was observed in control group. Experiment 2 found no significant differences among control, OT and E2+OT groups. The highest pregnancy rate, parturition rate and lambing rate were observed in OT groups (60%, 60% and 70%, respectively) and E2+OT groups (65%, 60% and 70%, respectively) compared to SEN, R, MIS and DIN groups (P<0.05).Conclusions:Oxytocin treatment alone or with estradiol could be used as a suitable dilator for improving reproductive efficiency during artificial insemination in fat-tailed ewes.

Protein glycation:a wolf in sweet sheep’s clothing behind neurodegeneration

At the beginning of the 16th century,Paracelsus coined the maxim:“the dose makes the poison”.This principle can be applied to all living organisms,including organs and cells.The brain and its glial and neuronal cells are no exception.Even small compounds that are essential for the life of brain cells can become truly toxic when overdosed.

Supplementation of Lycium barbarum residue increases the growth rate of Tan sheep by enhancing their feed intake and regulating their rumen microbiome and metabolome

Lycium barbarum residue(LBR),a by-product of L.barbarum processing,is packed with bioactive components and can be potentially utilized as a feed additive in animal husbandry.However,the fundamental understanding of its effectiveness on livestock animals is still lacking,particularly in ruminants.To explore the effects of LBR on the growth performance,rumen fermentation parameters,ruminal microbes and metabolites of Tan sheep,sixteen fattening rams(aged 4 mon)were fed a basal diet(CON,n=8)or a basal diet supplemented with 5%LBR(LBR,n=8).The experiment lasted for 70 d,with 10 d adaptation period and 60 d treatment period.The results showed that the LBR enhanced the average daily feed intake,average daily gain(P<0.05),and ruminal total volatile fatty acids(P<0.01)while decreasing ammonia-nitrogen concentration and rumen pH value(P<0.05).Additionally,the LBR improved the relative abundances of Prevotella,Succiniclasticum,Ruminococcus,Coprococcus,Selenomonas,and Butyrivibrio(P<0.05)and reduced the relative abundances of Oscillospira and Succinivibrio(P<0.05).The LBR altered the ruminal metabolome(P<0.01)by increasing the abundances of ruminal metabolites involved in amino acids(e.g.,L-proline,L-phenylalanine,L-lysine,and L-tyrosine),pyrimidine metabolism(e.g.,uridine,uracil,and thymidine),and microbial protein synthesis(e.g.,xanthine and hypoxanthine).In conclusion,LBR had positive effects on the growth rate of Tan sheep as well as on rumen fermentation parameters,rumen microbiome and rumen metabolome.

Etiological Agent, Pathogenesis, Diagnosis, Treatment, Measures for Prevention and Control of Caseous Lymphadenitis Disease in the Small Ruminants with Special Reference to Sheep

Caseous lymphadenitis (CL) is a chronic infectious disease caused by Corynebacterium pseudotuberculosis (C. pseudotuberculosis) that is transmitted mainly by contact with contaminated exudate wounds. Caseous lymphadenitis affects different species of animals and is considered an occupational zoonotic disease. CL is responsible for important economic losses in the small ruminant industry, which include decreased production, damaged quality of milk and wool, reproductive disorders, total or partial confiscation of carcasses, and depreciation of the skin. Caseous lymphadenitis disease can present in two clinical pictures: a skin or superficial picture and a visceral or deep picture. The presumptive diagnosis of CL in the skin is based on the exploration of superficial lymph nodes. These have little value in diagnosing visceral CL, where the main sign is emaciation. The prevention and control of CL involve identifying the skin condition and debriding the abscesses. In addition to the treatment of superficial lesions, the animal facilities must be repaired and adapted. To avoid exposure of negative herds to CL, new animals must be subjected to observation to identify any of the clinical manifestations. Another form of control is vaccination, though only some countries have commercial vaccines. General information on the etiological agent and its characteristics can be used to improve the understanding of this disease.

Cysticercus Tenuicollis in Visceral Organs of Goats and Sheep in Uganda: A Case Study in Lira Municipal Abattoir

Cysticercus tenuicollis is a metacestode stage of Taenia hydatigena residing in the visceral organs of small ruminants and its effects cause economic losses due to condemnation of visceral organs in slaughterhouses. This study reports on the prevalence of Cysticercus tenuicollis in small ruminants slaughtered in Lira Municipal Abattoir. A total of 70 sheep and 70 goats were sampled and examined after slaughter for the presence of Cysticercus tenuicollis in the visceral organs using standard meat inspection procedures. An abattoir data collection sheet was used to record data, which was then analysed in SPSS version 20. The study revealed 51.4% of goats and 68.6% of sheep to be infested with Cysticercus tenuicollis. Following the district of origin for the small ruminants, Otuke district had the highest prevalence of the parasite (82.6%), followed by Kole (72.4%), Alebtong (66.7%), Apac (59.4%) and Lira (31.4%). Cysticercus tenuicollis was more frequently seen in the intestines (57.8%) of sheep and goats than in any other visceral organs. The liver had a prevalence of 20.7%, the lungs 17.8%, the kidneys 3.5% and the fetal sac;(15.7%) in goats and (12.9%) in sheep. Cysticercus tenuicollis was detected in 68.8% of females and 58.8% of male small ruminants. It is recommended to routinely deworm goats and sheep by farmers most especially in districts with the highest prevalence of Cysticercus tenuicollis infestation. The sale of the condemned parts of sheep and goats and the feeding of dogs on these contaminated materials should be stopped forthwith. It is also being suggested that a national study be carried out to determine the prevalence and economic impact of Cysticercus tenuicollis in small ruminants.

Genomic signatures of selection,local adaptation and production type characterisation of East Adriatic sheep breeds

Background The importance of sheep breeding in the Mediterranean part of the eastern Adriatic has a long tradition since its arrival during the Neolithic migrations.Sheep production system is extensive and generally carried out in traditional systems without intensive systematic breeding programmes for high uniform trait production(carcass,wool and milk yield).Therefore,eight indigenous Croatian sheep breeds from eastern Adriatic treated here as metapopulation(EAS),are generally considered as multipurpose breeds(milk,meat and wool),not specialised for a particular type of production,but known for their robustness and resistance to certain environmental conditions.Our objective was to identify genomic regions and genes that exhibit patterns of positive selection signatures,decipher their biological and productive functionality,and provide a"genomic"characterization of EAS adaptation and determine its production type.Results We identified positive selection signatures in EAS using several methods based on reduced local variation,linkage disequilibrium and site frequency spectrum(eROHi,iHS,nSL and CLR).Our analyses identified numerous genomic regions and genes(e.g.,desmosomal cadherin and desmoglein gene families)associated with environmental adaptation and economically important traits.Most candidate genes were related to meat/production and health/immune response traits,while some of the candidate genes discovered were important for domestication and evolutionary processes(e.g.,HOXa gene family and FSIP2).These results were also confirmed by GO and QTL enrichment analysis.Conclusions Our results contribute to a better understanding of the unique adaptive genetic architecture of EAS and define its productive type,ultimately providing a new opportunity for future breeding programmes.At the same time,the numerous genes identified will improve our understanding of ruminant(sheep)robustness and resistance in the harsh and specific Mediterranean environment.

Research and Application of Compressed Fermented Chestnut Leaf Feed in Fattening Mutton Sheep

Chestnut leaves and bran were evenly mixed according to different mass ratios,and the mixtures were sprayed and inoculated with a certain amount of prepared EM microbial liquid,and then compressed into 70 cm×40 cm×30 cm blocks by a fully automatic yellow-storage block compression and packaging machine.The obtained blocks were packaged and sealed with plastic film,and placed in a freely ventilated place for more than 15 d of anaerobic fermentation,so as to obtain compressed fermented chestnut leaf block feed.[Results]Through the detection and analysis of nutritional components in the compressed fermented chestnut leaf block feed in the laboratory,the protein content was equal to or greater than 10.2%,which was 44.68%higher than that of unfermented chestnut leaf feed;the tannin content was equal to or greater than 638 mg/kg,which was 18.41%lower than that of the original feed;and the crude fiber content was equal to or greater than 19.5%,which was 14.09%lower than that of the original feed.[Conclusions]This study improves the palatability of chestnut leaf feed,increases the use efficiency of feed and reduces feeding cost.It is worth popularizing.

Developmental Changes of the FAS and HSL mRNA Expression and Their Effects on the Content of Intramuscular Fat in Kazak and Xinjiang Sheep

Twenty-four male Kazak sheep and 30 Xinjiang fine wool sheep at different ages were selected to investigate the development-dependent expression levels of fatty acid synthase （FAS） gene and hormone-sensitive lipase （HSL） gene in muscle and their effects on the contents of intramuscular fat （IMF）. Longissimus dorsal muscle was sampled to measure IMF and total RNA was extracted to determine FAS and HSL mRNA expression levels by real-time PCR. The results showed that： l） The IMF content increased continuously with growth and showed significant differences （P 〈 0.05） between different age groups in male Kazak sheep, but in Xinjiang fine wool sheep there was no such difference observed. Furthermore, the IMF contents in Kazak were much higher （P 〈 0.01） than that of the other breed from day 30 to 90. 2） FAS mRNA expression level was the highest （P 〈 0.05） on day 0 in Kazak sheep and then declined with growth, in the other breed the gene showed a d‘ecline-rise-decline-rise＇ expression manner as the animals grew. HSL mRNA expression level had a similar model in two breeds, in Kazak sheep it was the highest on day 0 （P 〈 0.05） and in Xinjiang fine wool sheep on day 30 （P 〈 0.01）, then both decreased after this term. 3） In male Kazak sheep, FAS and HSL mRNA expression level were both negatively related to IMF content （r= -0.485 （P = 0.02）, r= -0.423 （P = 0.05））, and the ratio of FAS/HSL expression exhibited significantly negatively related IMF contents. In male Xinjiang sheep, there were no obvious relationship between FAS and HSL expression and IMF content （P 〉 0.05）.

Effects of in Vitro Maturation Time of Oocytes on Sheep Nuclear Transfer Efficiency

[Objective] The study aimed to provide references for the time of oocyte maturation in vitro and enucleation in the course of sheep nuclear transfer(NT).[Method] Compared the effects of different maturation time of oocytes on enucleation efficiency and reconstructed embryo development by means of blind enucleation and fluorescence microscopy.[Result] Treatment of IVM(in vitro maturation)19-21 h was significantly higher than IVM 16-18 h treatment in oocyte maturation rate(P<0.05)and was significantly higher than IVM 22-24 h treatment in enucleation rate(P<0.05).Three treatments had no significant difference in cleavage rate and blastocyst rate(P>0.05),but IVM 19-21 h treatment was significantly higher than the other 2 treatments in average cell number of blastocysts(P<0.05).[Conclusion] The appropriate in vitro maturation time of oocytes was 19-21 h for sheep nuclear transfer,which could significantly improve the quality of blastocysts according to the cell number per blastocyst(P<0.05).

Comparison of Growth and Development Traits among Crossbreds of Dorset and Local Sheep Varieties in Gansu Province

In order to improve the meat production performance of local sheep varieties in Gansu Province, Dorset was introduced to crossbreed with the local sheep varieties, including Tan sheep, Small Tail Han sheep and Mongolia sheep. The offspring of different crossbreeding combinations were sampled randomly at different growth stages, and their growth and development traits were measured so as to screen out the best crossbreeding mode. The results showed that under the same crossbreeding mode, the growth rate of F3 was higher than that of F2, and of F2 was higher than that of F1. Among the F3 population, the growth rates of Dorset ×Han and Dorset × Mongolia hybrids were higher. Compared with those of Dorset ×Tan F3 hybrids, the body weights of male and female Dorset × Han and Dorset ×Mongolia F3 hybrids were increased by 5.59%, 4.40%, 5.93% and 3.76%, respectively. Among the F2 population, the growth rates of Dorset × Han and Dorset ×Mongolia hybrids were also higher. The body weights of male and female Dorset ×Han and Dorset × Mongolia F2 hybrids were higher than those of Dorset × Tan ×Han F2 hybrids by 5.99%, 3.67%, 9.80% and 5.00%, respectively. In the F1 population, the growth rates of Dorset × Han and Dorset × Mongolia hybrids were higher.Compared with those of Tan × Han F1 hybrids, the body weights of male and female Dorset × Han and Dorset × Mongolia F1 hybrids were increased by 11.32%,5.22%, 7.60% and 7.20%, respectively. Therefore, in the feeding area of Small Tai Han sheep, Mongolia sheep and Tan sheep, Dorset was the best sire for producing hybrid lambs. The economic benefit of crossbred offspring was obvious.

Effects of Lysine on the Expression of GHR mRNA in Sheep

[Objective] This study was to investgate the effects of lysine on the growth of sheep and its mechanism. [Method] Fifteen sheep about one-year old as experimental material were divided into three groups （group A, group B end group C）, into whose basal feed 0, 4 and 10 g h/sine were respectively added. After 28 d of feeding, the experimental sheep were all slaughtered for sampling; then total RNAs were extrac- ted from the samples and used to clone GHR and GAPDH genes via retrotrenscription for analyzing the expression abundance of GHR mRNA in Iongissimus dorsi muscle from different treatments. [Result] The expression of GHR mRNA in treatment B was significantly higher than that in treatment A（ P 〈0.01 ）, and significantly higher then that in treatment C （ P 〈0.05） ; while that in treatment C and treatment A was insignificantly different（ P 〉 0.05）. [ Conclusion] Addition of lysine into basal feed of sheep could dose-independently improve the expression of GHR gene in Iongissimus dorsi muscle.

Genetic Polymorphism in GDF8 Region of HU Sheep Based on Microsatellite DNA

[ Objective ] This study was to analyze the genetic polymorphism in GDF8 Region of HU sheep. [Method] Four microsatellite loci including BMS1591, TEXAN-2, FCB128 and BM81124 mapped on GDF8 region of chromosome No. 2 of sheep that may be correlated with growth performance were chosen to detect the molecular genetics foundation of growth performance of Hu sheep. [ Result] Four microsatellite loci detected were high in heterozygosity, more in effective alleles number and rich in polymorphic information, all the three indices passed through the high polymorphic level （PIC 〉0.5）. [ Conclusion ] The four microsatellite loci detected could be used to estimate the genetic polymorphism of growth performance of Hu sheep.

Effect of RPlys on Digestive Metabolism of Nitrogen in Sheep

[Objective] The aim was to study the effect of RPlys on digestive metabolism of nitrogen in sheep.[Method] The contribution of RPlys for nitrogen residual in sheep was researched by digestive metabolism test.[Result] The results showed that adding RPlys decreased excretion of urine nitrogen （P0.05） and had no significant effect on excretion of fecal nitrogen （P0.05）,and precipitation coefficient of nitrogen was increased （P0.05）.[Conclusion] RPlys is propitious to the aggradations of nitrogen in sheep.

HISTOCHEMICAL TECHNIQUES IDENTIFYING MAST CELLS IN PIG,CATTLE AND SHEEP

Carnoy′s fluid and neutral buffered formalin(NBF)have been proved to be good fixatives for preservation of mast cells in pig,cattle and sheep except NBF blocked staining of most porcine mast cells,especially those located in intestinal mucosa(MMC)and in thymus medulla(TMMC). Both toluidine blue and Alcian blue were the excellent stains generally,but Alcian blue stained more porcine mast cells than did toluidine blue( P <0 01). Staining with toluidine blue of a wide pH range(from 0 1 to 7 0)showed that porcine mast cells were not very pH dependent,but the dye at pH 0 5 seemed to have the strongest affinity for all mast cells in pigs and it was also suitable for bovine and ovine mast cell staining. In the three species,unlike in rodents,the Alcian blue method did not distinguish between mast cells in the intestinal mucosa(MMC)and those in the connective tissue of the intestinal submucosa,tongue and skin(CTMC). Porcine CTMC,but not MMC,fluoresced strongly when stained with berberine sulphate or with a mixture of berberine sulphate and acridine orange. It suggested that porcine CTMC contained heparin proteoglycan.

Seasonal Variation of Physiological and Biochemical Indexes of White-tibetan Sheep

In this study, to understand the variation regulation of physiological and biochemical indexs of White-Tibetan sheep with seasons, the physiological and bio- chemical indexs of White-Tibetan sheep in Hongyuan Areas of Sichuan Province in four seasons were measured. The results showed that the respiratory change range of white-Tibetan sheep in four seasons was from （32.74±21.33） to （49.96±17.62） times/min, and the variation ranges of body temperature and heart rate were from （39.27±1.05） to （39.73±0.31） ℃ and from （88.75±8.32） to （104.63±10.39） times/min, respectively. The indexes of WBC, MCV, MCH and MCHC in autumn and winter were extremely significantly lower than those in spring and summer, while RBC,HCT and RDW-CV in autumn and winter were extremely significantly higher than those in spring and summer, HGB and PLT changed in different seasons with no signifi- cance. The indexes of AST,TP, ALB, GLO and LDH in summer and autumn were relatively higher than those in winter and spring, while the indexes of PCHE, GLU, CHOL and CA in summer and autumn were relatively lower than those in winter and spring, however, the indexes of ALT and ALP were relatively higher in spring and autumn.

Quantitative Study on Expression of MSTN Gene in Different Tissues of Tibetan Sheep at Different Ages

[Objective] The aim was to investigate the difference in MSTN gene expression in different tissues of Tibetan sheep at different ages.[Method] According to the sequence（NM_001009428.1）published in GenBank,a pair of specific primers was designed to amplify part of cDNA sequence of MSTN by using QRT-PCR technique.The relative expression level of MSTN gene in rennet stomach,rumen,leg muscle and cardiac muscle of Tibetan sheep at different ages were analyzed.[Result] After normalization with β-actin gene,the relative expression level of MSTN gene in the 6-month-old Tibetan sheep was the highest and it was 2.52 times than that in 12-month-old Tibetan sheep（P0.05）,the relative expression level of MSTN gene in leg muscle was the highest among all tissues and it was 3 984.78 times than that in rumen（P0.01）.[Conclusion] The results established theoretical foundation for the correct use of MSTN antibody.

Developmental Changes of IGF-Ⅰ mRNA Expression Level in Sheep Muscle

[ Objective] To detect the mRNA of muscle insulin-like growth factorl （IGF-I） in the early development of Kazak sheep and Xinjiang fine-wool sheep, so as to provide information for the research about the early growth and development of sheep. [ Method] With real-time quan- titative PCR, the muscle IGF-I mRNA level was separately detected in two varieties of sheep at 2, 30, 60, 90 and 120 days old. Then the data was analyzed with SPSS software. [ Result] The IGF-I mRNA in sheep muscle first increased and then decreased with ages, peaking at 30 days old in Kazak sheep and at 60 days old in Xinjiang fine-wool sheep. The IGF-I expression level of Kazak sheep had no significant difference with Xinjiang fine-wool sheep at 2 or 90 days old （ P 〉0.05）, but was lower than that of the latter with extremely significant difference （ P 〈0.01 ） from 30 to 60 days old. [ Conclusion] The male Kazak sheep and Xinjiang fine-wool sheep have similar model of developmental changes of muscular IGF-I mRNA, but the expression level is different between these two species.

Analysis on Genetic Diversity and Isolation Mechanism by Distance of Different Ecological Type Sheep Breeds in Mon-golia Sheep Group

In the present study with Tan sheep, small-tailed Han sheep, Hu sheep, Tong sheep, and Wadi sheep, we detected the distribution of gene frequency of several microsatellite sites in different chromosomes, the result showed that： 1） Hu sheep was in the status of Hardy-Weinberg extreme disequilibrium （P 〈 0.01）, while populations including Tong sheep, small-tailed Han sheep, Tan sheep, and Wadi sheep were in Hardy-Weinberg equilibrium （P 〉 0.05）. 2） Variance analysis of the heterozygosity and poly- morphic information content at rnicrosatellite makers showed that there were not significant differences among populations as to heterozygosity and PIC （P 〉 0.05）, as to effective number of alleles there were not significant differences both among Tan sheep, Hu sheep, Tong sheep, and Wadi sheep, and between Wadi sheep and small-tailed sheep （P 〉 0.05）, but between the former three populations and the latter two populations, there were significant differences （0.01〈 P 〈0.05）. The variation levels of small-tailed Han sheep was the highest in the five populations based on microsatellite maker data, subsequently followed by Wadi sheep, Tong sheep, Tan sheep, and then Hu sheep. 3） The phylogenetic relationships of the five sheep populations in this study did not meet the mechanism of isolation by distance, and the genetic differentiation relationships among five sheep populations were not closely linearly correlative with their geography distribution. Our findings supported related records in literature： The five populations originated on different time stage from the primogenitor population and communicated genetically with each other thereafter in the process of natural and artificial selection and on different ecological environment.