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Hu sheep is an excellent short fat-tailed breed in China. Fat deposition in Hu sheep tail affects carcass quality and consumes a lot of energy, leading to an increase in feed cost. The objective of this study was to analyze the effects of HMGA1 polymorphism on tail fat weight in Hu sheep. Partial coding and non-coding sequences of HMGA1 were amplified with PCR and single nucleotide polymorphisms (SNP) of HMGA1 in 1163 Hu sheep were detected using DNA sequencing and KASPar technology. RT-qPCR analysis was performed to test HMGA1 expression in different tissues. The results showed that the expression of HMGA1 was higher in the duodenum, liver, spleen, kidney, and lung than in the heart, muscle, rumen, tail fat, and lymph. A mutation, g.5312 C > T, was detected in HMGA1; g.5312 C > T was significantly associated with tail fat weight, relative weight of tail fat (body weight), and relative weight of tail fat (carcass) (p < 0.05). The tail fat weight of the TT genotype was remarkably higher than that of the CC and TC genotypes. Therefore, HMGA1 can be used as a genetic marker for marker-assisted selection of tail fat weight in Hu sheep. [ABSTRACT FROM AUTHOR]

Background: This study investigated greenhouse gas (GHG) emission characteristics of lactating Holstein dairy cows in East China and provided a basis for formulating GHG emission reduction measures. GreenFeed system was used to measure the amount of methane (CH4) and carbon dioxide (CO2) emitted by the cows through respiration. Data from a commercial cow farm were used to observe the effects of parity, body weight, milk yield, and milk component yield on CH4 and CO2 emissions. Results: Mean herd responses throughout the study were as follows: 111 cows completed all experimental processes, while 42 cows were rejected because they were sick or had not visited the GreenFeed system 20 times. On average, lactating days of cows was 138 ± 19.04 d, metabolic weight was 136.5 ± 9.5 kg, parity was 2.8 ± 1.0, dry matter intake (DMI) was 23.1 ± 2.6 kg/d, and milk yield was 38.1 ± 6.9 kg/d. The GreenFeed system revealed that CH4 production (expressed in CO2 equivalent, CO2-eq) was found to be 8304 g/d, C H 4 ( C O 2 − e q) /DMI was 359 g/kg, C H 4 ( C O 2 − e q) /energy-corrected milk (ECM) was 229.5 g/kg, total CO2 production (CH4 production plus CO2 production) was 19,201 g/d, total CO2/DMI was 831 g/kg, and total CO2/ECM was 531 g/kg. The parity and metabolic weight of cows had no significant effect on total CO2 emissions (P > 0.05). Cows with high milk yield, milk fat yield, milk protein yield, and total milk solids yield produced more total CO2 (P < 0.05), but their total CO2 production per kg of ECM was low (P < 0.05). The total CO2/ECM of the medium and high milk yield groups was 17% and 27% lower than that of the low milk yield group, respectively. Conclusions: The parity and body condition had no effect on total CO2 emissions, while the total CO2/ECM was negatively correlated with milk yield, milk fat yield, milk protein yield, and total milk solids yield in lactating Holstein dairy cows. Measurement of total CO2 emissions of dairy cows in the Chinese production system will help establish regional or national GHG inventories and develop mitigation approaches to dairy production regimes. [ABSTRACT FROM AUTHOR]

Simple Summary: Increasing litter size is critical for the intensive sheep production system. Genetic marker-assisted selection (MAS) based on proven molecular indicators could enhance the efficacy of sheep selection with improving litter size traits. Many single nucleotide polymorphisms (SNPs) linked with litter size in Hu sheep and Small-tailed Han sheep have been identified. However, they usually explain a small portion of genetic variation and additional genetic markers linked with litter size have not been found. The present study investigated the potential SNPs in ten genes as candidate markers for improved litter size in sheep. As a result, nine SNPs in six out of ten genes can be served as useful genetic markers to improve the selection of litter size since they are significantly associated with litter size either in Hu sheep or Small-tailed Han sheep. Further, a combined haplotypes analysis of the two loci (LIFR: g.35862868C>T and LIFR: g.35862947G>T) revealed that H2H3 (CTTT) combined haplotypes had the largest litter size than the rest combined haplotypes and more than those with either mutation alone in Small-tailed Han sheep. Our knowledge is essential to implement the MAS in sheep and further to increase the profitability in the sheep industry. Hu sheep and Small-tailed Han sheep are the most widely raised and most famous maternal sheep breeds in China, which are known for precocious puberty, perennial oestrus and high fecundity (1–6 lambs each parity). Therefore, it is crucial to increase litter size of these two breeds for intensive sheep industry. The objective of this study was to identify potential genetic markers linked with sheep litter size located at ten genes. This study collected blood sample of 537 Hu sheep and 420 Small-tailed Han sheep with litter size of first parity. The average litter sizes in Hu sheep and Small-tailed Han sheep were 2.21 and 1.93. DNA-pooling sequencing method was used for detecting the potential single nucleotide polymorphisms (SNPs) in ten genes related to follicle development and female reproduction. SNPscan® was used for individually genotyping. As a result, a total of 78 putative SNPs in nine out of ten candidate genes (except NOG) were identified. In total, 50 SNPs were successfully genotyped in Hu sheep and Small-tailed Han sheep. After quality control, a total of 42 SNPs in Hu sheep and 44 SNPs in Small-tailed Han sheep were finally used for further analysis. Association analysis revealed that nine SNPs within six genes (KIT: g.70199073A>G, KITLG: g.124520653G>C, ADAMTS1: g.127753565T>C, ADAMTS1: g.127754640G>T, NCOA1: g.31928165C>T, NCOA1: g.32140565G>A, LIFR: g.35862868C>T, LIFR: g.35862947G>T and NGF: g.91795933T>C) were significantly associated with litter size in Hu sheep or Small-tailed Han sheep. A combined haplotypes analysis of the two loci (LIFR: g.35862868C>T and LIFR: g.35862947G>T) revealed that H2H3 (CTTT) combined haplotypes had the largest litter size than the rest combined haplotypes and more than those with either mutation alone in Small-tailed Han sheep. Taken together, our study suggests that nine significant SNPs in six genes can be served as useful genetic markers for MAS in sheep. [ABSTRACT FROM AUTHOR]

Corn straw and corncobs contain large amounts of crude fibers and are widely used in mutton sheep husbandry in northwest China. The aim of this study was to determine whether feeding with corn straw or corncobs affects lamb testis development. A total of 50 healthy Hu lamb at two-month-old (average body weight of 22.3 ± 0.1 kg) were randomly and equally divided into two groups, and the lambs were equally allocated to five pens in each group. The corn straw group (CS) received a diet containing 20% corn straw, whereas the corncobs group (CC) received a diet containing 20% corncobs. After a 77-day feeding trial, the lambs, except the heaviest and lightest in each pen, were humanely slaughtered and investigated. Results revealed no differences in body weight (40.38 ± 0.45 kg vs. 39.08 ± 0.52 kg) between the CS and CC groups. Feeding diet containing corn straw significantly (P < 0.05) increased testis weight (243.24 ± 18.78 g vs. 167.00 ± 15.20 g), testis index (0.60 ± 0.05 vs. 0.43 ± 0.04), testis volume (247.08 ± 19.99 mL vs. 162.31 ± 14.15 mL), diameter of seminiferous tubule (213.90 ± 4.91 μm vs. 173.11 ± 5.93 μm), and the number of sperm in the epididymis (49.91 ± 13.53 × 108/g vs. 19.34 ± 6.79 × 108/g) compared with those in the CC group. The RNA sequencing results showed 286 differentially expressed genes, and 116 upregulated and 170 downregulated genes were found in the CS group compared with the CC group. The genes affecting immune functions and fertility were screened out. Corn straw decreased the mtDNA relative copy number in the testis (P < 0.05). These results suggest that compared with corncobs, feeding corn straw in the early reproductive development stage of lambs increased the testis weight, diameter of seminiferous tubule and the number of cauda sperm. [Display omitted] • There were 286 DEGs in testis between corn straw and corncobs groups. • The genes closely related to testis function were screened out. • Feeding corn straw in the early reproductive development stage of lambs increased the number of sperm in the epididymis. [ABSTRACT FROM AUTHOR]

Sunflower seed husk (SH) and rape straw (RS) are widely used in mutton sheep husbandry in the Hexi Corridor of China. This study explored whether or not a pre-puberty lamb diet consisting of sunflower SH and RS affects ram testis development. Fifty 60-day-old healthy Hu ram lambs (average body weight of 22.3 ± 0.1 kg) were randomly divided into two groups. In each treatment group, 25 lambs were allocated to five pens (five lambs per pen). The SH group received a diet containing 20 % SH, and the RS group received a diet containing 20 % RS. After a 77-day feeding trial, three lambs, except for the heaviest and lightest in each pen, were humanely slaughtered and investigated. Results revealed that the two groups had no difference in body weight (39.23 ± 0.52 kg vs. 38.53 ± 0.46 kg, P = 0.321). However, the testis weight (288.74 ± 23.45 g vs. 215.18 ± 17.96 g), volume (294.29 ± 25.39 mL vs. 208.67 ± 16.63 mL), epididymis weight (38.38 ± 1.44 g vs. 33.86 ± 1.37 g), testicular index (0.74 ± 0.06 vs 0.56 ± 0.05), and epididymis sperm count (4.88 ± 0.92 ×109/g vs. 2.27 ± 0.69 ×109/g) in the SH group were significantly higher than those in the RS group (P < 0.05). SH reduced the mtDNA relative copy number (P < 0.01) in the testis and increased the total antioxidant capacity (3.41 ± 0.94 U/mg prot vs. 1.54 ± 0.38 U/mg prot, P = 0.05). RNA sequencing results showed 50 differentially expressed genes, with 27 genes upregulated and 23 genes downregulated in the SH group compared with the RS group. KEGG analysis revealed that the pathways related to polyunsaturated fatty acid metabolism, and vitamin digestion and absorption were enriched. The findings suggest that feeding SH in the early reproductive development stage of lambs is more beneficial for testis development and spermatogenesis compared with feeding RS. • Feeding sunflower seed husk during the peri-puberty was more conducive to ram reproductive than feeding rape straw. • Feeding sunflower seed husk stimulated testis development and increased the number of sperm in the epididymis. • The pathways related to polyunsaturated fatty acid metabolism, vitamin digestion and absorption were enriched. [ABSTRACT FROM AUTHOR]

Antibiotics are increasingly found in dairy products. To ensure consumer safety, rapid screening methods which are accurate and cost-effective are highly in demand. A multiplexed detection technology was tested for quantification of these four kinds of antibiotics simultaneously in milk. The visual microarray technology based on enzyme-linked immunosorbent assays was utilized in this method, which can detect multiple target molecules simultaneously. This colorimetric technology provides direct results that can be detected using common commercial microplate scanners. The limit of detection (LOD) were calculated as 3.30, 3.39, 2.42 and 4.88 μg kg−1 for quinolones, tetracycline, lincomycin and streptomycin, respectively. The limits of quantity (LOQ) were defined as 8.97, 8.43, 5.36 and 10.97 μg kg−1 for quinolones, tetracycline, lincomycin and streptomycin, respectively. The accuracy of method was also adequate for these four substances with the recovery rates ranging from 77.6% to 116.4% were obtained for the detection of practical samples. According to our evaluation, this methodology can be used for rapid screening of antibiotics in internal quality control programs in dairy industry. • The multiplexed detection method for testing veterinary antibiotics in milk were evaluation. • The ELISA-based visualization microarray chip technique using 96-well microplate. • The limit of detection are less than the MRL established in China, the CAC and the EU. • The accuracy of method was adequate for these four veterinary antibiotics. [ABSTRACT FROM AUTHOR]

Growth traits is a critical economic trait for animal husbandry. In this study, the SNPs of CTNNA3 and CAP2 genes were investigated to check whether they are associated with growth traits (body weight, body height, body length and chest circumference) in Hu sheep. The result of the association analysis indicated that the mutation in CTNNA3 (g.2018018 A > G) were associated significantly with body weight, body height, body length and chest circumference (P < 0.05), the mutation in CAP2 (g.8588 T > C) were associated significantly with body height at 140, 160, 180 days (P < 0.05), AA and CC of CTNNA3 and CAP2 were the dominant genotypes associated with growth traits in Hu sheep. Moreover, combined effect analyses indicated that the growth traits with combined genotypes AA CTNNA3 -CC CAP2 and AA CTNNA3 -CT CAP2 were higher than those with genotype GG CTNNA3 -CT CAP2 . RT-qPCR indicated that CTNNA3 expression levels were significantly higher in liver and lung than in other nine tissues (P < 0.05), CAP2 expression levels were significantly higher in bone, heart, liver, lung and duodenum than in other six tissues (P < 0.05). In conclusion, CTNNA3 and CAP2 polymorphisms could be used as genetic markers for improving growth traits in Hu sheep husbandry., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The insulin like growth factor 1 receptor (IGF-IR) plays an important role in regulating growth and development. To investigate the effects of IGF-IR polymorphisms on the economic traits of dairy goats, polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and DNA sequencing methods were used to screen single nucleotide polymorphisms (SNPs) within 9 IGF-IR fragments in Xinong Saanen dairy goat (XS, n = 268) and Guanzhong dairy goat (GZ, n = 440). Consequently, two SNPs, including NC&#95;007319: g.26688 C>T (Leu 608 Leu) and NC&#95;007319: g.28273 T>C within exon 9 and intron 10 were identified in R8 and R9 loci, respectively. At R8 locus, three genotypes were found, including CC, CT and TT, with genotypic frequencies of 0.11, 0.65 and, 0.24 respectively in XS goats, and 0.13, 0.78 and 0.09 in GZ goats; three genotypes which are C 1 C 1 , C 1 T 1 and T 1 T 1 were also found in R9 locus, with the genotypic frequencies of 0.48, 0.20 and 0.32 in XS goats, and 0.43, 0.22 and 0.35 in GZ goats, respectively. Based on χ 2 test, both XS and GZ populations were deviated from Hardy-Weinberg equilibrium at above two loci. The association analysis revealed that XS goats with CC genotype at R8 locus had heavier milk density than the CT ones (P < 0.05). At R9 locus, the body height of GZ goats with C 1 C 1 and T 1 T 1 genotypes was significantly higher than those with C 1 T 1 genotype (P < 0.01 or P < 0.05). The individuals of GZ goat with C 1 C 1 genotype had longer body length than those with T 1 T 1 genotype (P < 0.05). The individuals of XS with T 1 T 1 and C 1 T 1 genotypes had higher body height than those with C 1 C 1 genotype (P < 0.05). This study can provide theoretical and practical significances to improve the milk production traits and promote the growth and development in two Chinese indigenous dairy goat breeds., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The Small Tailed Han sheep and Hu sheep are two prolific local sheep in China. In this study, the polymorphisms of BMPR-IB (Bone morphogenetic protein receptor IB), BMP-15 (Bone morphogenetic protein 15) and FSHR (follicle stimulating hormone receptor) were investigated to check whether they are associated with litter size in Small Tailed Han sheep and Hu sheep. Consequently, three polymorphisms, FecB mutation in BMPR-IB (c.746A>G), FecG mutation in BMP-15 (c.718C>T) and the mutation (g. 47C>T) in FSHR were found in the above two sheep breeds with a total number of 1630 individuals. The single marker association analysis showed that the three mutations were significantly associated with litter size. The ewes with genotype FecBB/FecBB and FecBB/FecB+ had 0.78 and 0.58 more lambs (p < 0.01) than those with genotype FecB+/FecB+, respectively. The heterozygous Han and Hu ewes with FecXG/FecX+ genotype showed 0.30 (p = 0.05) more lambs than those with the FecX+/FecX+ genotype. For FSHR gene, the ewes with genotype CC had 0.52 (p < 0.01) and 0.75 (p < 0.01) more lambs than those with genotypes TC and TT, respectively. Combined effect analyses indicated an extremely significant interaction (p < 0.01) between the random combinations of BMPR-IB, BMP-15 and FSHR genes on litter size. In addition, the Han and Hu ewes with BB/G+/CC genotype harbor the highest litter size among ewes analyzed in current study. In conclusion, BMPR-IB, BMP-15 and FSHR polymorphisms could be used as genetic markers in multi-gene pyramiding for improving litter size in sheep husbandry.

Background: The objective of this study was to establish a culture system and elucidate the unique characteristics of a bovine mammary epithelial cell line in vitro., Methodology: Mammary tissue from a three year old lactating dairy cow (ca. 100 d relative to parturition) was used as a source of the epithelial cell line, which was cultured in collagen-coated tissue culture dishes. Fibroblasts and epithelial cells successively grew and extended from the culturing mammary tissue at the third day. Pure epithelial cells were obtained by passages culture., Principal Findings: The strong positive immunostaining to cytokeratin 18 suggested that the resulting cell line exhibited the specific character of epithelial cells. Epithelial cells cultured in the presence of 10% FBS, supraphysiologic concentrations of insulin, and hydrocortisone maintained a normal diploid chromosome modal number of 2n=60. Furthermore, they were capable of synthesizing beta-casein (CSN2), acetyl-CoA carboxylase-alpha (ACACA) and butyrophilin (BTN1A1). An important finding was that frozen preservation in a mixture of 90% FBS and 10% DMSO did not influence the growth characteristics, chromosome number, or protein secretion of the isolated epithelial cell line., Conclusions: The obtained mammary epithelial cell line had normal morphology, growth characteristics, cytogenetic and secretory characteristics, thus, it might represent an useful tool for studying the function of Chinese Holstein dairy cows mammary epithelial cell (CMECs).