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.

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.

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.

High-efficiency Embryo Cryopreservation Technology for Mutton Sheep

Embryo cryopreservation is an important part of embryo biotechnology.It plays a key role in the development of quality animal husbandry.However,the effect of in-vivo(in-vitro)embryo freezing of cattle and sheep in China has not reached an expected level,which limits the commercial application of embryo transfer technology.The technical bottleneck that needs to be broken through is that embryos are subject to mechanical damage and protective agent toxicity during freezing and thawing.This paper summarized the successful application of plant antifreeze protein in vitrification preservation of pig embryos,which makes this technology widely used in animal husbandry production,and is of great significance in accelerating the large-scale breeding of improved livestock and saving endangered animals.

Gait analysis in swine,sheep,and goats after neurologic injury:a literature review

Medical research on neurologic ailments requires representative animal models to validate treatments before they are translated to human clinical trials.Rodents are the predominant animal model used in neurological research despite limited anatomic and physiologic similarities to humans.As a result,functional testing designed to assess locomotor recovery after neurologic impairment is well established in rodent models.Comparatively,large r,more clinically relevant models have not been as well studied.To achieve similar locomotor testing standardization in larger animals,the models must be accessible to a wide array of researchers.Non-human primates are the most relevant animal model fo r translational research,however ethical and financial barriers limit their accessibility.This review focuses on swine,sheep,and goats as large animal alternatives for transitional studies between rodents and non-human primates.The objective of this review is to compare motor testing and data collection methods used in swine,sheep,and goats to encourage testing standardization in these larger animal models.The PubMed database was analyzed by searching combinations of swine,sheep,and goats,neurologic injuries,and functional assessments.Findings were categorized by animal model,data collection method,and assessment design.Swine and sheep were used in the majority of the studies,while only two studies were found using goats.The functional assessments included open pen analysis,treadmill walking,and guided free walking.Data collection methods included subjective behavioral rating scales and objective tools such as pressure-sensitive mats and image-based analysis software.Overall,swine and sheep were well-suited for a variety of assessment designs,with treadmill walking and guided free walking offering the most consistency across multiple trials.Data collection methods varied,but image-based gait analysis software provided the most robust analysis.Future studies should be conducted to standardize functional testing methods after neurologic impairment in large animals.

A computational framework for improving genetic variants identification from 5,061 sheep sequencing data

Background Pan-genomics is a recently emerging strategy that can be utilized to provide a more comprehensive characterization of genetic variation.Joint calling is routinely used to combine identified variants across multiple related samples.However,the improvement of variants identification using the mutual support information from mul-tiple samples remains quite limited for population-scale genotyping.Results In this study,we developed a computational framework for joint calling genetic variants from 5,061 sheep by incorporating the sequencing error and optimizing mutual support information from multiple samples’data.The variants were accurately identified from multiple samples by using four steps:(1)Probabilities of variants from two widely used algorithms,GATK and Freebayes,were calculated by Poisson model incorporating base sequencing error potential;(2)The variants with high mapping quality or consistently identified from at least two samples by GATK and Freebayes were used to construct the raw high-confidence identification(rHID)variants database;(3)The high confidence variants identified in single sample were ordered by probability value and controlled by false discovery rate(FDR)using rHID database;(4)To avoid the elimination of potentially true variants from rHID database,the vari-ants that failed FDR were reexamined to rescued potential true variants and ensured high accurate identification variants.The results indicated that the percent of concordant SNPs and Indels from Freebayes and GATK after our new method were significantly improved 12%-32%compared with raw variants and advantageously found low frequency variants of individual sheep involved several traits including nipples number(GPC5),scrapie pathology(PAPSS2),sea-sonal reproduction and litter size(GRM1),coat color(RAB27A),and lentivirus susceptibility(TMEM154).Conclusion The new method used the computational strategy to reduce the number of false positives,and simulta-neously improve the identification of genetic variants.This strategy did not incur any extra cost by using any addi-tional samples or sequencing data information and advantageously identified rare variants which can be important for practical applications of animal breeding.

Effects of LPA on the development of sheep in vitro fertilized embryos and attempt to establish sheep embryonic stem cells

Lysophosphatidic acid(LPA)is a small molecule glycerophospholipid,which regulates multiple downstream signalling pathways through G-protein-coupled receptors to achieve numerous functions on oocyte maturation and embryo development.In this study,sheep in vitro fertilized embryos were applied to investigate the effects of LPA on early embryos development and embryonic stem cell establishment.At first,the maturation medium containing estrus female sheep serum and synthetic oviduct fluid(SOF)were optimized for sheep IVF,and then the effects of LPA were investigated.From 0.1 to 10μmol L^(–1),LPA had no significant effect on the cleavage rate(P>0.05),but the maturation rate and blastocyst rate increased dependently with LPA concentration(P<0.05),and the blastocyst morphology was normal.When the LPA concentration was 15μmol L^(–1),the maturation rate,cleavage rate and blastocyst rate decreased significantly(P<0.05),and the blastocyst exhibited abnormal morphology and could not develop into highquality blastocyst.Besides,the exogenous LPA increases the expression of LPAR2,LPAR4,TE-related gene CDX-2and pluripotency-related gene OCT-4 in sheep early IVF embryos with the raise of LPA concentration from 0.1 to 10μmol L^(–1).The expression of LPAR2,LPAR4,CDX-2 and OCT-4 from the LPA-0.1μmol L^(–1)to LPA-10μmol L^(–1)groups in early embryos were extremely significant(P<0.05),while the expression of these genes significantly decreased in 15μmol L^(–1)LPA-treated embryos compared with LPA-10μmol L^(–1)group(P<0.05).The inner cell mass in 15μmol L^(–1)LPA-treated embryos was also disturbed,and the blastocysts formation was abnormal.Secondly,the sheep IVF blastocysts were applied to establish embryonic stem cells.The results showed that LPA made the blastocyst inoculated cells grow towards TSC-like cells.They enhanced the fluorescence intensity and mRNA abundance of OCT-4 and CDX-2 as the concentration increased from 0 to 10μmol L^(–1),while 15μmol L^(–1)LPA decreased OCT-4 and CDX-2 expression in the derived cells.The expression of CDX-2 and OCT-4 in the blastocyst inoculated cells of LPA-1μmol L^(–1)group and LPA-10μmol L^(–1)group extremely significantly increased(P<0.05),but there was significant decrease in LPA-15μmol L^(–1)group compared with LPA-10μmol L^(–1)group(P<0.05).Meanwhile,the protein expression of LPAR2 and LPAR4 remarkably increased after treatment of LPA at 10μmol L^(–1)concentration.This study references the IVF embryo production and embryonic stem cell research of domestic animals.

MicroRNA-370-5p inhibits pigmentation and cell proliferation by downregulating mitogen-activated protein kinase kinase kinase 8 expression in sheep melanocytes

In mammals,microRNAs(miRNAs)play key roles in multiple biological processes by regulating the expression of target genes.Studies have found that the levels of miR-370-5p expression differ significantly in the skins of sheep with different hair colors;however,its function remains unclear.In this study,we investigated the roles of miR-370-5p in sheep melanocytes and found that the overexpression of miR-370-5p significantly inhibited cell proliferation(P<0.01),tyrosinase activity(P=0.001)and significantly reduced(P<0.001)melanin production.Functional prediction revealed that the 3′-untranslated region(UTR)of MAP3K8 has a putative miR-370-5p binding site,and the interaction between these two molecules was confirmed using luciferase reporter assays.In situ hybridization assays revealed that MAP3K8 is expressed in the cytoplasm of melanocytes.The results of quantitative RT-PCR and Western blotting analyses revealed that overexpression of miR-370-5p in melanocytes significantly inhibits(P<0.01)MAP3K8 expression via direct targeting of its 3′UTR.Inhibition of MAP3K8 expression by siRNA-MAP3K8 transfection induced a significant inhibition(P<0.01)of melanocyte proliferation and significant reduction(P<0.001)in melanin production,which is consistent with our observations for miR-370-5p.Target gene rescue experiments indicated that the expression of MAP3K8 in melanocytes co-transfected with miR-370-5p and MAP3K8-cDNA(containing sites for the targeted binding to miR-370-5p)was significantly rescued(P≤0.001),which subsequently promoted significant increases in cell proliferation(P<0.001)and melanin production(P<0.01).Collectively,these findings indicate that miR-370-5p plays a functional role in inhibiting sheep melanocyte proliferation and melanogenesis by downregulating the expression of MAP3K8.

Phylogenetic Relationship and Molecular Divergence Dating Using SRY Gene Polymorphism about Four Ladoum Sheep Lineages in Senegal

Animal genetic resources are playing a vital role in livestock production and are essential to food security. The present study aims to contribute to a better understanding genetic local sheep breeds and to elucidate the phylogenetic relationships through the evolution of the SRY gene in four different lineages of Ladoum sheep raised in Senegal. After a brief analysis of genetic diversity, the phylogenetic relationships and molecular dating were inferred through haplotype networks and four phylogenetic reconstruction methods. The different haplotype networks are constructed with NETWORK ver. 5.0.0.0 using the Median-Joining method. Phylogenetic trees were reconstructed using neighbor-joining, maximum parsimony, maximum likelihood and Bayesian inference. The robustness of the nodes in phylogenetic trees of the three first methods was assessed by 1000 bootstraps. For Bayesian inference, the posterior probability distribution of the trees was estimated by 4 MCMC chains. 5,000,000 generations were performed for each of the chains by sampling the different parameters every 1000 generations. Results show a low polymorphism. Haplotypic diversity is much higher than the average nucleotide divergence between all pairs of haplotypes. The majority and central haplotype indicates a close relationship between “Batling” and “Tyson” individuals. “Birahim” lineage is very distinct from the rest. Phylogenetic trees confirm two genetically separate clades between “Birahim” and the other lineages. The period of divergence between “Birahim” lineage versus the common ancestor of the other three lineages was 2504 years ago. The polyphyly revealed in “Birahim” lindicates that this lineage does not contain the common ancestor of all individuals who compose it. It could therefore be derived from two or more sheep breeds with a common ancestor, Ovis aries. The monophyletic clade appears to be a group including a common ancestor and all of its genetic descendants. This group, bringing together the other three lineages, is in the process of being structured into sub-lineages. This study is the first to show that there are only two genetic lines within ladoum sheep in Senegal.

Effects of Antimicrobial Peptides on Production,Slaughter Performance and Blood Routine of Tan Sheep

[Objectives]This study was conducted to analyze effects of antimicrobial peptides added to the diet of Tan sheep on their production, slaughter performance and blood composition. [Methods] Ninety two four-month-old Tan sheep were randomly divided into two treatment groups according to their body weight, 46 in each group. The control check group(CK) was feed with conventional diet, and the experimental group was fed with the addition of antimicrobial peptide on the basis of the conventional diet, with the added amount of 2.5 g/sheep per day. The experimental period was 60 d. [Results] The incidence rate was 75.06% lower in the experimental group than in the CK. The average daily weight gain per sheep was 11.27% higher in the experimental group than in the CK(P<0.05). The feed conversion ratio was 8.45% lower in the experimental group than in the CK(P<0.05). The average daily gross profit per sheep was 12.12% higher in the experimental group than in the CK. For slaughter performance, the data difference of each item was not significant. The PH at 45 min and 24 h after slaughter was within the normal range of fresh mutton. The cooked meat percentage and water loss rate showed no significant differences(P>0.05). The marbling ranged from 2.45 to 2.50, indicating that the fat content was moderate, and the difference between groups was not significant(P>0.05). The flesh color ranged from 3.00 to 3.15, between light red and bright red, belonging to the normal color of mutton, and the difference between groups was not significant(P>0.05). The shear force was between 2.50 and 2.65, without a significant difference between groups(P>0.05). The white blood cells, lymphocytes and platelets in the experimental group were lower than those in the CK(P<0.01). The erythrocytes and hemoglobin in the erythrocyte group were higher than those in the CK(P<0.05). The neutrophils and monocytes in the experimental group were lower than those in the CK(P<0.05). [Conclusions] This study provides a technical basis for the rational use of antimicrobial peptides and their application in ruminants.

Study on Breeding Practices and Reproductive Performance of Black-Head Somali Sheep under Traditional Management System: The Case of Awbarre District, Eastern Ethiopia

The study was conducted in the Awbarre district of the Fafen zone of the Somali regional state of Ethiopia. The objective of the study was to assess the breeding practices and reproductive performance of Black-head Somali sheep under a traditional management system. Purposive and simple random sampling techniques were used to select targeted kebeles and households, respectively. A total of 120 households were selected from four kebeles, each of 30 households, based on the production system and sheep population. Semi-structured questionnaires, group discussions, key informants interviews and field observations were used to generate the required data. The primary purpose of keeping sheep was for income generation, followed by saving as a future asset. The majority (89.2%) of the respondents separated male and female animals during herding. The selection criteria for breeding rams were appearance, growth, pedigree, and color while for breeding ewes were appearance, adaptability, pedigree, color, and lamb growth. The overall weaning age of Black-head Somali sheep in the study area was 3.7 months for both males & females. The castration of male sheep was common for the purpose of fattening, fattening with breeding control and breeding control as well. The castration is mainly performed during the summer and autumn and the methods of castration were both traditional and modern methods, the traditional castration method being the most important one in pastoral areas. The age of sexual maturity was 7.64 months for rams and 8.97 months for ewe’s male and female lambs in the pastoral area and 8.42 & 8.38 for rams & ewes in agro-pastoral and overall lambing interval was 11 months. On average, the ewe of Black-head Somali sheep in pastoral & agro-pastoral could produce 9.49 & 9.57 lambs, respectively in their lifetime. As the pastoralists and agro-pastoralists indicated the source of the breeding ram was their own, so the exchange of breeding ram is recommended to minimize the risk of inbreeding and further studies of on-farm performance investigation would be necessary to be carried out so as to understand the uniqueness of the breed better.

Improving the Local Sheep in Gansu via Crossing with Introduced Sheep Breeds Dorset and Borderdale

In order to improve the meat performance of local sheep in Gansu Province,Dorset and Borderdale were introduced to crossbreed with local sheep which were Tan sheep,Small-tail Han sheep and Mongolia sheep. The offspring under different crossbreeding combinations were sampled randomly at the different growing stage to measure their growth traits so as to select optimize the crossbreeding mode. The results indicated that,for the same crossbreeding mode,the growth rate of progeny was in order F3】 F2】 F1; for the F3 progeny,the combinations Dorset- Borderdale- Small tail Han sheep and Dorset- Borderdale- Mongolia sheep gave a higher growth rate,with a body weight of 1. 57%,3. 17%,8. 23%,1. 15% higher in male and female individuals than the counterparts of Dorset and Tan sheep and Small tail Han sheep; for the F2 progeny,the combinations Dorset- Borderdale- Small tail Han sheep and Dorset- Borderdale- Mongolia sheep also gave a higher growth rate,with a body weight of 2. 15%,4. 53%,9. 21% and 2. 75% higher in male and female individuals than the counterparts of Dorset and Tan sheep and Small tail Han sheep; for the F1 progeny,the combination Borderdale and Small tail Han sheep assumed a higher growth rate,with a body weight of 3. 23%,6. 07%,7. 42% and 8. 66% higher in male and female individuals than the counterparts of Borderdale- Mongolia sheep and Tan sheep- Small tail Han sheep,respectively. Therefore,in the Small-tail Han sheep and Mongolia sheep producing regions,the F2 or F3progeny bred by using Dorset or Borderdale sheep as male parent to cross with local breeds,or the hybrid lambs of Small-tail Han sheep and Borderdale sheep as highly qualified commodity,would produce significant economic benefit. Moreover,the novel breeds obtained by crossing were the valuable genetic resource for breeding meat sheep.

Analysis of Physiological and Biochemical Indexes of White-tibetan Sheep at Different Months of Age

To study the physiological and biochemical indexes of White-tibetan sheep in plateau environment, we measured the physiological and biochemical inde- xes of White-tibetan sheep at 3, 6, 9, 12, 15, 18,21 and 24 months of age. The results showed that the body temperature, respiration and heart rate of White-ti- betan sheep at 3 - 24 months of age were （38.89 ±0. 56） - （39.83 ± 0.32） ℃, （26.00±6.67 ） - （58.64 ± 12.67 ） times/rain and （ 83.90 ± 7.64） - （111.36 ±7.46） times/rain, respectively. The blood physiological indexes of WBC, HCT and RDW-CV at 3, 6, 15 and 18 months of age were lower than those at 9, 12, 21 and 24 months of age. On the contrary, the indexes of RBC, MCV, MCH and MCHC at 3, 6, 15 and 18 months of age were higher than those at 9, 12, 21 and24 months of age, while HGB and PLT did not vary with months of age. For blood biochemical indexes, ALT, AST, TP, ALB, LDH and CHOL reached the maximums at 21 months of age, while ALP, PCHE and GLU reached the maximums at 3 months of age. Besides, the GLO and GA reached the maxi- mums at 18 and 24 months of age, respectively. The physiological and biochemical indexes of White-tibetan sheep followed certain rules in growth and development process, and might be affected by plateau climate and season.

High gene flows promote close genetic relationship among finewool sheep populations(Ovis aries) in China

The aim of our present study was to construct genetic structure and relationships among Chinese fine-wool sheep breeds. 46 individuals from 25 breeds or strains were genotyped based on the Illumina Ovine 50K SNP array. Meanwhile, genetic variations among 482 individuals from 9 populations were genotyped with 10 microsatellites. In this study, we found high genetic polymorphisms for the microsatellites, while 7 loci in the Chinese superfine Merino strain （Xinjiang types） （CMS） and 5 loci in Gansu alpine superfine-wool sheep strain （GSS） groups were found deviated from Hardy-Weinberg equilibrium （HWE）. Genetic drift FsT=0.019 （P〈0.001） and high gene flows were detected in all the 7 fine-wool sheep populations. Phylogenetic analysis showed fine-wool sheep populations were clustered in a group independent from the Chinese indigenous breeds such that the 7 fine-wool sheep clustered distinct from Liangshan semifine-wool sheep （LS） and Hu sheep （HY） reflected by different population differentiation analyses. Overall, our findings suggested that all fine-wool sheep populations have close genetic relationship, which is consistent with their breeding progress. These populations, therefore, can be regarded as open-breeding populations with high levels of gene flows. Furthermore, the two superfine-wool strains, viz., CMS and GSS, might be formed by strong artificial selection and with frequent introduction of Australian Merino. Our results can assist in breeding of superfine-wool sheep and provide guidance for the cultivation of new fine-wool sheep breeds with different breeding objectives.

The Levels of Genetic Differentiation of Small-Tailed Han Sheep and Tan Sheep Populations Using Structural Loci

Using the method of ＂random sampling in typical colonies of the central area of the habitat＂ and several electrophoresis techniques, the variations of 17 structural loci encoding blood proteins in 60 Small-Tailed Han sheep and 73 Tan sheep were examined and compared with those of 14 other sheep populations in China and other countries to investigate their levels of genetic differentiation. The average heterozygosities of Small-Tailed Han sheep and Tan sheep were 0.2360 and 0.2587, respectively. The average polymorphic information content values were 0.1974 and 0.2102, respectively. The average effective numbers of alleles were 1.5723 and 1.5751, respectively. The coefficients of gene differentiation in the four groups （including 4, 6, 13, and 16 sheep populations, respectively） were 0.049323, 0.059987, 0.1728, and 0.201256, respectively, indicating that the degree of gene differentiation at the structural loci was the least in Hu sheep, Tong sheep, Small-Tailed Hart sheep, and Tan sheep; followed by the above-mentioned four sheep populations and two Mongolian sheep populations; and was the highest in sheep populations belonging to the Mongolian sheep group, South Asian sheep, and European sheep. The earlier researchers＇ conclusions that both Small-Tailed Han sheep and Tan sheep evolved from Mongolian sheep were further verified by the results of this study. Hu sheep, Tong sheep, Small-Tailed Han sheep, and Tan sheep were decreasingly affected by the bloodline of Mongolian sheep to different degrees. The relationships among sheep populations were not closely related to the geographical distances among sheep populations.

JIVET Research on Texel Sheep

The present study was conducted to explore ways of JIVET research on Texel sheep,and to provide technical support for the improvement of the JIVET technology system for research on Texel sheep.Superovulation was conducted on 4-8-week old Texel sheep,and in-vivo ovum collection,in-vitro oocyte maturation and fertilization,and fertilized-embryo culture and transplantation were adopted to perform JIVET research on Texel sheep.The results showed that 296 available oocytes were obtained at an average of 74 oocytes per sheep;205 fertilized eggs were obtained at the 2-4 cell stage at an average of 51.25 eggs per sheep and a cleavage rate of 69.26%;and 66 of the fertilized eggs were transplanted to 11 receptor sheep.Six sheep were conceived at a conception rate of 54.55%,and 11 lambs were born.These results indicated that the present test could be used as a method for the study of JIVET technique on Texel sheep.

Study on In-vitro Production Technology of Embryos from Young Dorper Sheep

This study was conducted to investigate the in-vitro production technology of embryos from young Dorper sheep, so as to provide technical support for the utilization of ovarian follicles in young Dorper sheep. Tests were conducted from the induction of Dorper sheep of 4 to 8 weeks old using follicle stimulating hormone(FSH) and pregnant horse serum(PMSG), collection of oocytes, in-vitro oocyte maturation-fertilization-zygote cultivation and 2-4-cell-stage fertilized ovum transfer. The results showed that 585 oocytes were collected from eight Dorper sheep at the age of 4 and 8 weeks, with an average of 73.13 oocytes/sheep. 346 of the 2-4-cell-stage fertilized eggs were obtained, whose cleavage rate was 59.15%. 77 in-vitro fertilized eggs at 2-4-cell stage were transplanted into 17 recipient sheep, seven of which were pregnant and gave birth to 13 "test-tube sheep" with a conception rate of 41.18%. It is indicated that the hormone induction technique, in-vitro oocyte maturation-fertilization-zygote cultivation technique and 2-4-cell-stage fertilized ovum transfer technique used in this study can serve as effective techniques for the in-vitro production of embryos from Dorper sheep of 4-8 weeks old.

Countermeasures and Recommendations for High Quality Development of Tan Sheep Industry in Ningxia

Tan sheep industry is a characteristic and superior agricultural industry in Ningxia,and it is also an enriching industry that helps in poverty alleviation and increases farmers’income.The local government has been committing to building the"Yanchi Tan Sheep"brand and has made remarkable achievements.In order to explore the resource efficiency and quality of Tan sheep industry,the current situations and advantages of brand development,this paper made an empirical research through field investigations.The research was mainly concentrated on breeding scale,industrial integration,brand building,breeding benefits,and policy support.After a comprehensive evaluation,it came up with the recommendation that the Tan sheep industry should take the high-quality,high-end and green development road.

The CRISPR/Cas9 induces large genomic fragment deletions of MSTN and phenotypic changes in sheep

The CRISPR/Cas9 system has been extensively used to engineer genetic loci for the generation of knockouts, insertions, and point mutations in animal models. However, many mutations that have been reported in animals are small insertions or deletions. This study used the CRISPR/Cas9 system to induce large DNA fragment deletions in MSTN via three guide RNAs in sheep. This successfully achieved the precise gene editing of the ovine MSTN gene by injecting both Cas9 m RNA and sg RNAs into embryos at the one-cell stage. Of 10 edited animals, 3 animals(30%) exhibited large genomic fragment deletions(~5 kb). Furthermore, the body weights of these 3 animals were significantly different(P0<0.0001, P15=0.001, P30=0.005, P60=0.027) between lambs with large deletions and wildtype lambs. In addition, the edited lambs were also significantly different(P0<0.0001, P15<0.0001, P30=0.002, P60=0.011) compared with wildtype. These results suggest that the generated MSTN knockout sheep is a reliable and effective animal model for further study. Furthermore, this method is time-and labor-saving, and efficient for the creation of animal models for agriculture, biology, and medicine.

Effects of Chinese herbal medicine on plasma glucose,protein and energy metabolism in sheep

Background： The use of antibiotics in animal diets is facing negative feedback due to the hidden danger of drug residues to human health. Traditional Chinese herbal medicine has been used to replace antibiotics in the past two decades and played an increasingly important role in livestock production. The present study was carried out to assess the feeding effects of a traditional nourishing Chinese herbal medicine mixture on kinetics of plasma glucose, protein and energy metabolism in sheep. Ruminal fermentation characteristics were also determined. Methods： Four sheep were fed on either mixed hay （MH-diet） or MH-diet supplemented with 2% of Chinese herbal medicine （mixture of Astragalus root, Angelica root and Atractylodes rhizome; CHM-diet） over two 3S-day periods using a crossover design. The turnover rate of plasma glucose was measured with an isotope dilution method using [U-^13C]glucose. The rates of plasma leucine turnover and leucine oxidation, whole body protein synthesis （WBPS） and metabolic heat production were measured using the [1-^13C]leucine dilution and open circuit calorimetry. Results： Body weight gain of sheep was higher （P = 0.03） for CHM-diet than for MH-diet. Rumen pH was lower （P = 0.02）, concentration of rumen total volatile fatty acid tended to be higher （P = 0.05） and acetate was higher （P = 0.04） for CHM-diet than for MH-diet. Turnover rates of plasma glucose and leucine did not differ between diets. Oxidation rate of leucine tended to be higher （P = 0.06） for CHM-diet than for MH-diet, but the WBPS did not differ between diets. Metabolic heat production tended to be greater （P = 0.05） for CHM-diet than for MH-diet. Conclusions： The sheep fed on CHM-diet had a higher body weight gain and showed positive impacts on rumen fermentation and energy metabolism without resulting in any adverse response. Therefore, these results suggested that the Chinese herbal medicine mixture should be considered as a potential feed additive for sheep.