• Asian-Australasian Journal of Animal Sciences
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• v.32 no.10
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• pp.1540-1547
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• 2019

Objective: This study was conducted to evaluate the effects of tannins and cellulase on growth performance, nutrient digestibility, blood profiles, intestinal morphology, and carcass characteristics in Hu sheep. Methods: A total of 48 three-month-old meat Hu sheep ($25.05{\pm}0.9kg$) were blocked based on body weight, and randomly allotted to 4 treatments with 3 replicates of 4 sheep each. The experiment lasted for 80 d, and dietary treatments were as follows: i) CON, control diet; ii) TAN, CON+0.1% tannins; iii) CEL, CON+0.1% cellulase; iv) TAN+CEL, CON+0.1% tannins and 0.1% cellulase. Results: Compared with CON, CEL, and TAN+CEL had greater (p<0.05) final body weight (FBW) and average daily gain but lower (p<0.05) feed conversion ratio, while FBW of TAN+CEL was lower (p<0.05) than that of CEL. The apparent total tract digestibility (ATTD) of dry matter in TAN, CEL, and TAN+CEL groups were higher (p<0.05) than that in CON. CEL and TAN+CEL groups had greater (p<0.05) ATTD of crude fiber compared with TAN and CON, while TAN group had lower (p<0.05) ATTD of crude protein than other treatments. TAN, CEL, and TAN+CEL groups increased (p<0.05) serum globulin and alkaline phosphatase but decreased (p<0.05) albumin/globulin. Serum total protein was greatest for TAN+CEL, intermediate for TAN and CEL and least for CON (p<0.05). TAN+CEL group increased (p<0.05) dressing percentage compared with CON, while the backfat thickness of CEL was lower (p<0.05) than that of CON. The villus height of jejunum and ileum in CEL and TAN+CEL groups were greater (p<0.05) than that in CON, and the crypt depth and villus height: crypt depth of jejunum were increased (p<0.05) in TAN, CEL, and TAN+CEL groups. Conclusion: The addition of tannins and cellulase together promoted nutrient digestion, liver protein synthesis and intestinal development and thus improved growth performance and carcass characteristics.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.5
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• pp.711-715
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• 2013

To investigate the effect of restricted grazing time on behavior of Tan sheep on desert steppe, forty 4-months old male Tan sheep with an original body weight (BW) of $15.62{\pm}0.33$ kg were randomly allocated to 4 grazing groups which corresponded to 4 different restricted grazing time treatments of 2 h/d (G2), 4 h/d (G4), 8 h/d (G8) and 12 h/d (G12) access to pasture. The restricted grazing times had a significant impact on intake time, resting time, ruminating time, bite rate and movement. As the grazing time decreased, the proportion of time spent on intake, bite rate and grazing velocity significantly (p<0.05) increased, but resting and ruminating time clearly (p<0.05) decreased. The grazing months mainly depicted effect on intake time and grazing velocity. In conclusion, by varying their foraging behavior, Tan sheep could improve grazing efficiency to adapt well to the time-limited grazing circumstance.

• Food Science of Animal Resources
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• v.42 no.4
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• pp.580-592
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• 2022

The aim of the present study was to evaluate the effectiveness of Lycium barbarum polysaccharide (LBP) on lipid oxidation and protein degradation in Tan sheep meatballs during the frozen period. The meatballs were treated with LBP at 0.01%, 0.02%, and 0.03% and stored at -18±1℃ for 0, 3, 6, 9, and 12 weeks. The effects of LBP treatment were investigated using the contents of total volatile basic nitrogen (TVB-N), texture profile (TP), thiobarbituric acid reactive substances (TBARS), colour, and pH values, compared with 0.02% butylated hydroxytoluene treatment and the blank control. The results showed that LBP treatment significantly decreased TBARS content compared with the control, which confirmed LBP to be a highly effective component in preventing lipid oxidation of Tan sheep meatballs during frozen storage, and protein degradation in Tan sheep meatballs had a significant inhibition effect because of TVB-N value reduction. In addition, the colour, TP and pH values of meatballs treated with LBP were improved dramatically. To further determine the quality changes of the blank control and all treated groups during storage, the comprehensive score evaluation equation based on principal component analysis was obtained: Y=0.51632Y₁+0.29589Y₂ (cumulative contribution rate=81.221%), and the 0.02% LBP-treated group had a higher comprehensive score than the other groups, and the quality of LBP-treated meatballs was better as well. In summary, LBP may reduce or inhibit lipid oxidation and protein degradation, and enhance overall quality and shelf-life in prepared meat products.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.9
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• pp.1229-1233
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• 2006

To find the candidate genes concerned with ovulation rate of sheep, Differential Display Reverse Transcription Polymerase Chain Reaction was employed to find the differently expressed cDNA controlling ovulation in the Small Tail Han sheep of polyembryony and in Tan sheep of single birth. Twenty-four primer pairs of three anchored primers and eight arbitrary primers were assembled to amplify the specialized bands from these sheep. Positive cross tests were applied to optimize the ascertainable PCR conditions in which different special bands can be identified by silver strain in one PCR tube. After eliminating the false positive PCR products by Northern hybridization, 24 differential display bands were acquired from the ovary in the Small Tail Han sheep. These EST bands were sequenced and 18 different ESTs were found in which five ESTs had several copies and 13 ESTs had only one copy. Comparing these ESTs with homologous sequences by BLAST in the GenBank, there were six ESTs with known open reading frame (ORF) and function, three ESTs with known ORF and no function, and 9 ESTs without homologous sequence. These ESTs partly represent several genes such as NOS2, tensin, TCRA, CDKN1A, ESR1 and ACTB which express especially in Small Tail Han sheep.

• Animal Bioscience
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• v.35 no.9
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• pp.1340-1350
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• 2022

Objective: Luxi Black Head sheep (LBH) is the first crossbreed specialized for meat production and was developed by crossbreeding Black Head Dorper sheep (DP) and Small Tailed Han sheep (STH) in the farming areas of northern China. Research on the genomic variations and selection signatures of LBH caused by continuous artificial selection is of great significance for identifying the genetic mechanisms of important traits of sheep and for the continuous breeding of LBH. Methods: We explored the genetic relationships of LBH, DP, and several Mongolian sheep breeds by constructing phylogenetic tree, principal component analysis and linkage disequilibrium analysis. In addition, we analysed 29 whole genomes of sheep. The genome-wide selection signatures have been scanned with four methods: heterozygosity (H_P), fixation index (F_ST), cross-population extended haplotype homozygosity (XP-EHH) and the nucleotide diversity (𝜃_π) ratio. Results: The genetic relationships analysis showed that LBH appeared to be an independent cluster closer to DP. The candidate signatures of positive selection in sheep genome revealed candidate genes for developmental process (HoxA gene cluster, BCL2L11, TSHR), immunity (CXCL6, CXCL1, SKAP2, PTK6, MST1R), growth (PDGFD, FGF18, SRF, SOCS2), and reproduction (BCAS3, TRIM24, ASTL, FNDC3A). Moreover, two signalling pathways closely related to reproduction, the thyroid hormone signalling pathway and the oxytocin signalling pathway, were detected. Conclusion: The selective sweep analysis of LBH genome revealed candidate genes and signalling pathways associated with developmental process, immunity, growth, and reproduction. Our findings provide a valuable resource for sheep breeding and insight into the mechanisms of artificial selection.

• Parasites, Hosts and Diseases
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• v.54 no.3
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• pp.301-305
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• 2016

In order to determine the effect of various hosts on feeding performance of Rhipicephalus (Boophilus) microplus, we used 3 mammalian species as hosts, cattle (Qinchuan), sheep (Tan), and rabbits (Japanese white rabbit) for infesting ticks. Five hundreds of R. microplus larvae were exposed to each animal (3 animals/host species). Tick recoveries were 11.0%, 0.47%, and 5.5% from cattle, sheep, and rabbits, respectively. The averages of tick feeding periods were not significantly different on cattle, sheep, and rabbits, 28.8, 25.3, and 26.7 days, respectively. The average weights of individual engorged female from cattle, sheep, and rabbits were 312.5, 219.1, and 130.2 mg, respectively and those of egg mass weights each to 85.0, 96.6, and 17.8 mg. The highest egg hatching rate was in the ticks from cattle (96.0%), followed by those from rabbits (83.0%) and sheep (19.2%). These data suggest that rabbits could be as an alternative host to cultivate R. microplus for evaluating vaccines and chemical and biological medicines against the tick in the laboratory, although the biological parameters of ticks were less than those from cattle.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.8
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• pp.1241-1245
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• 1999

Nine two-year old sheep fitted with rumen and duodenum cannulas were used to study the effect of controlling protozoa flora on the degradation and utilization of dietary fibre and protein in the rumen and on nitrogenous flow to the duodenum. There were three groups in this experiment: defaunation (DF); partial defaunation (PDF); faunation (F) as control. Results showed that: 1,There were no differences between treatments in dietary DM degradation in the rumen, but defaunation and partial defaunation increased the quantity of nitrogenous material in the rumen and the flow of N to duodenum. 2, partial defaunation and defaunation improved the degradabilities of dietary NDF, ADF and HC, but there were no differences between the defaunated and partially defaunated groups. 3, Partial defaunation decreased the degradability of dietary protein in the rumen. There was no difference between defaunated and faunated groups. 4, Defaunation and partial defaunation increased the quantity of total N (TN) and microbial N (MCN) in the rumen and the amounts entering the duodenum. The protozoa N (PN) flow in the faunated group was higher than that in the partially defaunated group, and the amino acid pattern in the digesta at the proximal duodenum in the defaunated group was closer to the ideal amino acid pattern. 5, There were differences in the mole percent of acetic, propionic, total-VFAs and the non-glucogenic to glucogenic VFAs ratio (NGR) value in the rumen fluids. The order was as follows: mole percent of acetate: F>PDF>DF; mole percent of propionate: DF>PDF>F; total-VFAs: PDF>F>DF; NGR: F>PDF>DF.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.11
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• pp.1591-1598
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• 2002

The effect of different dietary structural carbohydrate (SC) to nonstructural carbohydrate (NSC) ratios on fiber degradation, digestion, flow, apparent digestibility and rumen fluid characteristics was studied with a design using 18 wethers fitted with permanent rumen and duodenum cannulae. All sheep were divided into six groups randomly, receiving six diets with varying SC to NSC ratios. All diets contained the same proportion of wheat straw and concentrate. The dietary SC to NSC ratios were adjusted by adding cornstarch to the concentrate supplements. The duodenal and fecal flows of dry matter (DM), neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose (HC) and cellulose (CEL) were estimated using chromium-mordanted wheat straw as a flow marker. The degradation parameters of wheat straw DM, NDF, ADF, HC and CEL were determined by incubating the ground wheat straw in nylon bags in the rumen for different periods of time. There was no effect (p>0.05) of the different dietary SC to NSC ratios on rumen pH or $NH_3$-N, but acetate, propionate and butyrate concentrations were significantly affected (p<0.05 or p<0.01) by dietary SC to NSC ratios in the rumen fluid. When the dietary SC to NSC ratio was 2.86, the highest rumen degradability of wheat straw DM, NDF, ADF and CEL was found, but the highest apparent rumen digestibilities of DM, NDF, ADF, HC and CEL occurred at a 2.64 SC to NSC ratio. However, because of compensatory digestion in the hindgut, the apparent digestibilities of DM, NDF, ADF, HC and CEL were highest when the dietary SC to NSC ratio was 2.40. In conclusion, there is a optimal range of dietary SC to NSC ratios (between 2.86 and 2.40) that is beneficial to maximize wheat straw fiber degradation and apparent digestibility.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.10
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• pp.1374-1382
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• 2001

Fifteen Inner Mongolian wethers with permanent ruminal and duodenal cannulas were used to study the effects of dietary rumen-undegradable protein (RUP) to rumen-degradable protein (RDP) ratios or protein sources on fiber digestion in the gastrointestinal tract and ruminal fluid characteristics. Fiber digestion and ruminal fermentation were not affected (p>0.05) by dietary RUP to RDP ratios (from 1.54 to 0.72). Soybean meal supplementation improved ruminal digestion. Fish meal supplementation increased (p<0.05) the ruminal degradability of fiber. The different RUP to RDP ratios (from 1.54 to 0.72) did not influence (p>0.05) ruminal fluid pH, but there were differences (p<0.05) in ruminal fluid $NH_3-N$ concentration because of urea replacement. Soybean meal as a dietary protein source decreased (p<0.05) ruminal fluid pH and increased (p<0.05 or p<0.01) $NH_3-N$, acetate, propionate and butyrate concentrations in the rumen. Fish meal as a dietary protein source decreased (p<0.05 or p<0.01) ruminal $NH_3-N$ and acetate concentrations and increased (p<0.05) ruminal propionate concentration. It can be concluded that dietary protein sources have more significant effect on fiber digestion and ruminal fermentation than different dietary RUP to RDP ratios, when the dietary crude protein requirements of growing sheep are satisfied.

• Animal Bioscience
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• v.35 no.10
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• pp.1556-1565
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• 2022

Objective: Tan lambs (n = 36, 3 mo old, 19.1±0.53 kg) were used to assess effects of dietary guanidinoacetic acid (GAA) and rumen-protected methionine (RPM) on growth performance, carcass traits, meat quality, and serum parameters. Methods: Lambs were randomly assigned to three treatment groups, with 6 pens per group and 2 lambs per pen. Dietary treatments were: basal diet alone (I); basal diet supplemented with 0.08% GAA+0.06% RPM (II); and basal diet supplemented with 0.08% GAA+0.08% RPM (III). Diets were provided three times a day for 90 d. Intake per pen was recorded daily and individual lamb body weight (BW) was measured monthly. Carcass traits were measured after slaughter and meat quality at the end of the experiment, blood samples were taken on a subgroup of lambs for analysis of indicators mostly related to protein metabolism. Results: Final BW and average daily gain for the first and second month, and for the entire experiment were greater in Treatment II compared to Treatment I (p<0.05), whereas feed to gain ratio was lower (p<0.05). Treatment II had the optimal dressing percentage and net meat weight proportion, as well as crude protein and intramuscular fat concentrations in muscles. Treatment II improved meat quality, as indicated by the greater water holding capacity, pH after 45 min and 48 h, and lower shear force and cooking loss. Dietary supplementation of GAA and RPM also increased the meat color a^* and b^* values at 24 h. Finally, Treatment II increased total protein, and serum concentrations of albumin and creatinine, but decreased serum urea nitrogen concentrations, indicating improved protein efficiency. Conclusion: In this study, 0.08% GAA+0.06% RPM supplementation improved growth performance and meat quality of Tan lambs.