• Asian-Australasian Journal of Animal Sciences
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• v.25 no.12
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• pp.1660-1666
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• 2012

Cystic echinococcosis (CE), one of the world's most geographically widespread diseases, still represents a considerable economic and public health significance, although a variety of methods has been used to control the disease. It has been demonstrated that genetic factors, especially variations in MHC loci, can influence the outcome of CE infection in the human population. The study described here was designed to determine whether variation in MHC-DQB1 was associated with susceptibility or resistance to CE in sheep. If so, it would lay a theoretical foundation for breeding disease resistance sheep in future. This study was carried out on 204 Chinese Merino sheep, including 101 CE sheep and 103 healthy controls. The polymorphism of MHC-DQB1 exon 2 was detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method, and $x^2$ test was used to compare genotype frequencies between CE sheep and healthy controls. A total of 22 alleles and 42 genotypes were identified in DQB1 exon 2 in Chinese Merino sheep. In addition, $x^2$ test showed that frequencies of DQB1-TaqIaa and DQB1-HaeIIInn genotypes were significantly higher in the healthy group (82.5% and 57.3%, respectively) than that in the CE group (57.4% and 28.9%, respectively) (both p values = 0, OR = 0.286, 0.303, respectively), suggesting that these genotypes appeared to be associated with resistance to CE. Whereas, frequencies of DQB1-TaqIab and DQB1-HaeIIImn genotypes were significantly higher in the CE group (36.9% and 32.0%, respectively), as compared with the healthy group (16.5% and 11.15%, respectively) (p = 0.001, 0.001 and OR = 2.963, 3.629, respectively), indicating that these genotypes might be associated with susceptibility to CE. It is concluded that the genetic polymorphism within MHC-DQB1 might influence immune responses to pathogens, thus leading to the development of CE or protection against CE in Chinese Merino sheep, which would pave the way for breeding disease resistance sheep in future.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.7
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• pp.922-928
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• 2000

The effects of animal species and supplements on rumen fluid characteristics, plasma urea-N (PUN) concentration, plasma urea-N pool size, urea-N degradation in the gut and urea-N net flux (urea-N synthesis rate) were studied in goats and sheep, with some minor differences detected. The animals were fed either chopped rice straw ad libitum+200 g soybean meal (SBM), or chopped rice straw ad libitum+190 g soybean meal+300 g sago meal (SBM+SM) for 14 days. The supplements were isonitrogenous (80 g crude protein/animal/d). [$^{14}C$]-urea was used as the marker for urea metabolism studies. Two animals from each species were fed either supplement in a cross-over design in two periods. The results showed that rumen pH was significantly (p<0.001) lower in animals fed SBM+SM than those fed SBM supplement. The ammonia concentrations of rumen fluid were significantly (p<0.01) higher in sheep (382.9 mg N/L) than goats (363.1 mg N/L) when fed SBM supplement but lower (282.5 mg N/L) than that of goats (311.0 mg N/L) when fed SBM+SM supplement. Total VFA concentrations were significantly (p<0.05) higher in animals fed SBM+SM supplement than those fed SBM supplement. Goats had significantly (p<0.01) higher molar proportions of acetate (79.1, 77.7%, respectively) than sheep (75.8, 74.0%, respectively) in both supplements. The molar proportion of acetate was significantly (p<0.05) higher, while that of butyrate lower in animals fed SBM supplement than those fed SBM+SM supplement. In animals fed SBM supplement, the molar proportion of propionate was significantly (p<0.01) higher in sheep (18.0%) than in goats (15.6%), but in animals fed SBM+SM, the molar proportion of butyrate was significantly (p<0.01) higher (9.6%) in sheep than in goats (7.2%). Plasma urea-N concentration, plasma urea-N pool size, urea-N degradation in the gut, urea-N net flux and the fraction of urea-C from the blood entering the rumen were not significantly different between goats and sheep fed either supplement. However, PUN concentration was significantly (p<0.05) lower in animals fed SBM+SM supplement (average of 13.8 mg N/100 ml) than in those fed SBM supplement (average of 16.5 mg N/100 ml). The urea net flux was significantly (p<0.05) higher in goats (average of 14.5 g N/d) than sheep (average of 12.9 g N/d), and animals fed SBM supplement showed higher (average of 14.9 g N/d) urea net flux than animals fed SBM+SM supplement (average of 12.9 g N/d). A significant (p<0.05) positive correlation was observed between urea-N net flux and urea-N degradation; urea-N net flux and pool size; urea-N net flux and urea excretion in the urine; and PUN and rumen ammonia in goats. While in sheep, significant (p<0.05) positive correlation was observed between urea-N net flux and urea excretion in the urine; and PUN and rumen ammonia.

• Applied Biological Chemistry
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• v.8
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• pp.21-28
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• 1967

Two experiments with 32 sheep were conducted to study the effects of feeding the same amount of diet per day at different meal frequencies on ration digestibility, energy utilization, rate of gain, body composition and efficiency of gain. The results obtained are as follows: (1) The ingestion by sheep of the same amount of feed per day in 8 meals, 1 meal plus 7 ruminal inflations-deflations, and in 1 meal caused no different effect in the digestibility of the nutrients and energy, or the ME value of the diet. (2) Heat production per unit of metabolic size per unit of dietary intake was markedly lower for sheep ingesting 8 meals or administered 1 meal plus 7 ruminal inflations-deflations per day than for sheep fed 1 meal per day. (3) Body weight gain was significantly greater by sheep fed 8 meals per day or 1 meal plus 7 ruminal inflations-deflations than by those fed 1 meal per day. However, the gain in DM and energy of wool was not affected by frequency o( meals. (4) Sheep ingesting 8 meals or administered 1 meal plus 7 ruminal inflations-deflations per day gained body protein, fat and energy at a more rapid and efficient rate than sheep fed 1 meal per day. (5) Sheep fed 8 meals per day gained greater proportion of fat, protein and ash in the gained portion of the bodies than did 1 meal fed sheep. (6) An attempt was made to establish the possible explanations by which the frequency of ingesting meals exerts its effects.

• Korean Journal of Agricultural Science
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• v.28 no.2
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• pp.78-84
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• 2001

This study was analyzed by PCR technique with specific primer in order to investigate the characteristics of ${\beta}$-lactoglobulin (${\beta}$-LG) gene 5'flanking region in Korean native goat. This work confirmed amplified product of 1,077 bp fragments obtained from the amplification of ${\beta}$-LG promoter from genomic DNA using PCR in Korean native goat. The nucleotide sequence of ${\beta}$-LG gene 5'flanking region in Korean native goat as compared with that of sheep ${\beta}$-LG were different at 46 base of 897 nucleotides, and showed high homology as about 94.9% each breed. Especially we confirmed that the difference of nucleotide sequences between Korean native goat and sheep were consisted of $T{\rightarrow}C$ substitution and $C{\rightarrow}T$ substitution reversely. As a consequences, the sequences of ${\beta}$-LG gene 5'flanking region showed a high homology between Korean native goat and sheep. Furthermore we should be studied that relationships between the control of gene expression and nucleotide sequences of transcription factor in Korean native goat.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.4
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• pp.533-540
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• 2019

Objective: This study evaluated the growth, digestibility and rumen fermentation between goats and sheep fed a fattening diet fortified with linseed oil. Methods: Twelve 3 to 4 months old male goats and sheep were randomly allocated into two dietary treatment groups in a $2(species){\times}2$ (oil levels) factorial experiment. The treatments were: i) goats fed basal diet, ii) goats fed oil-supplemented diet, iii) sheep fed basal diet, and iv) sheep fed oil-supplemented diet. Each treatment group consisted of six animals. Animals in the basal diet group were fed with 30% alfalfa hay and 70% concentrates at a rate equivalent to 4% of their body weight. For the oil treatment group, linseed oil was added at 4% level (w:w) to the concentrate portion of the basal diet. Growth performance of the animals was determined fortnightly. Digestibility study was conducted during the final week of the feeding trial before the animals were slaughtered to obtain rumen fluid for rumen fermentation characteristics study. Results: Sheep had higher (p<0.01) average daily weight gain (ADG) and better feed conversion ratio (FCR) than goats. Oil supplementation did not affect rumen fermentation in both species and improved ADG by about 29% and FCR by about 18% in both goats and sheep. The above enhancement is consistent with the higher dry matter and energy digestibility (p<0.05), as well as organic matter and neutral detergent fiber digestibility (p<0.01) in animals fed oil- supplemented diet. Sheep had higher total volatile fatty acid production and acetic acid proportion compared to goat. Conclusion: The findings of this study suggested that sheep performed better than goats when fed a fattening diet and oil supplementation at the inclusion rate of 4% provides a viable option to significantly enhance growth performance and FCR in fattening sheep and goats.

• 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.1
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• pp.55-60
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• 2016

The aim of the present study is to determine the characteristics of genotype and phenotype of Echinococcus granulosus derived from wild sheep and to compare them with the strains of E. granulosus sensu stricto (sheep-dog) and E. granulosus camel strain (camel-dog) in Iran. In Khojir National Park, near Tehran, Iran, a fertile hydatid cyst was recently found in the liver of a dead wild sheep (Ovis orientalis). The number of protoscolices (n=6,000) proved enough for an experimental infection in a dog. The characteristics of large and small hooks of metacestode were statistically determined as the sensu stricto strain but not the camel strain (P=0.5). To determine E. granulosus genotype, 20 adult worms of this type were collected from the infected dog. The second internal transcribed spacer (ITS2) of the nuclear ribosomal DNA (rDNA) and cytochrome c oxidase 1 subunit (COX1) of the mitochondrial DNA were amplified from individual adult worm by PCR. Subsequently, the PCR product was sequenced by Sanger method. The lengths of ITS2 and COX1 sequences were 378 and 857 bp, respectively, for all the sequenced samples. The amplified DNA sequences from both ribosomal and mitochondrial genes were highly similar (99% and 98%, respectively) to that of the ovine strain in the GenBank database. The results of the present study indicate that the morpho-molecular features and characteristics of E. granulosus in the Iranian wild sheep are the same as those of the sheep-dog E. granulosus sensu stricto strain.

• Asian-Australasian Journal of Animal Sciences
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• v.9 no.3
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• pp.309-313
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• 1996

This experiment was carried out to investigate the effect of rumen-protected lysine (RPLys) on growth rate, feed efficiency and plasma amino acid concentrations in sheep. RPLys was supplemented at the level of 0% ($T_1$), 0.2% ($T_2$) and 0.4% ($T_3$) of total DMI with 24 sheep in a 56 day feeding trial. The results are summarized as follows: 1. live weight gain of sheep in groups $T_1$, $T_2$ and $T_3$ was 219, 216 and 244 g/d, and was significantly (p < 0.05) higher for $T_3$ through the entire experiment. 2. Feed intake was not affected by RPLys supplementation. 3. The group fed $T_3$ had a significantly (p < 0.05) better feed efficiency than the groups fed $T_1$ and $T_3$. The response of $T_3$ was higher in growing period II of feeding low protein basal diet than in period I. 4. Plasma lysine concentrations tended to be higher with supplementing RPLys, but there were no differences between $T_2$ and $T_3$. 5. Supplementing RPLys in the diets increased plasma concentrations of arginine, asparagines, threonine, serine, valine and leucine compared with sheep receiving no RPLys. In contrast, plasma histidine was lower in sheep fed the supplementing RPLys than fed the diet $T_1$ with significant (p < 0.05) difference.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.4
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• pp.363-372
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• 1999

This experiment was carried out to estimate an optimal lime and nitrogen levels on the growth control of sheep sorrel in mountainous pastures of Taekwalyon areas. The dry matter yield of sheep sorrel was recongnized significantly differences between the N levels and lime levels, respectively. Most effective growth control of sheep sorrel showed an over the N levels of 21kg/10a under the ranges of lime levels of 200~300kg/10a per annum. The highest dry matter yield of sheep sorrel was obtained at the N level of 16kg/10a under the N level of 48kg/10a per annum. The highest growth control effect of sheep sorrel was obtained at 2nd and 4th cuts, and 1st, 2nd and 4th cuts under the ranges of lime levels of 200~300kg/10a, and the N level of 48kg/10a per annum, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.2
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• pp.179-186
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• 1995

In the present study, nutritional status of some minerals in sheep grazed on native pasture was investigated in dry area, Ningxia district, of the People's Republic of China. Samples of some forages and blood of sheep were collected for two seasons, dry (March) and rainy (August) seasons. The Ca contents of forages (wheat straw, green-pea straw and some wild grasses) were relatively high as compared with that required ordinarily as standard, but on the contrary, the P content was much lower than that of standard. Consequently, Ca/P ratio was very high in cost of the roughages sampled in the region. Trace elements, Cu and Zn, content of forage samples were fairly low, and the contents of Mo and Fe were fairly high, particularly in some wild grasses, when the values were compared with that required normally. The Ca level in blood of sheep was in a range accepted as normal, and the other macro minerals(Mg and P) were contained at relatively high levels as compared with the values observed ordinarily, but not at a toxic level. With trace minerals, the plasma Fe level was extremely high as compared with the standard level, although there were no disorders due to toxicity, and Mo level in plasma was a little lower than the lower limit described as a normal. The plasma levels of other trace elements (Cu, Zn and Se) in all the animals were within the range accepted as normal. There would be no clear differences in mineral nutrition of sheep between dry and rainy seasons. These results could suggest that there is no severe unbalance and/or imbalance, and grazing sheep in the Ningxia area of midland China have no problems relating to the nutritional status of minerals.