Induction of oestrus in Saanen goats at early breeding season by intravaginal progesterone sponges (MAP) or by prostaglandin F(2)alpha injections. Effect on different age groups

Twenty-one maiden and 29 pluriparous milking Ankara Saanen goats received either two i.m. injections of PGF(2)alpha (n=25) or intravaginal MAP sponges (n=25) early in November at the start of the breeding season. About twice as many pluriparous goats as maiden goats exhibited estrus after either treatment (87% vs. 47%). Breeding after this induced estrus caused pregnancies in 62% of the pluriparous goats, but only in 24% of the maiden animals. Maximal concentrations of progesterone were reached 11 days after the start of the MAP treatment. Progesterone declined to basal levels two to four days after sponge withdrawal. A significant slower progesterone increase also resulting in lower maximal concentrations could be observed in maiden goats. Luteolysis was evident in all animals within 24 h after PGF(2)alpha injection. Nine goats (six maiden and three pluriparous) did not exhibit Heat after the second injection and showed only a slow increase of progesterone. It seems that noncyclic animals are less sensitive to MAP treatment than to the first PGF(2)alpha injection. Goats at the beginning of the breeding season may react after a premature interruption of corpus luteum function (after second PGF(2)alpha injection) with delayed or inadequate follicular function.     

Genotyping of Novel SNPs in BMPR1B,BMP15, and GDF9 Genes for Association with Prolificacy in Seven Indian Goat Breeds

Goats form the backbone of rural livelihood and financial security systems in India but their population is showing decreasing trend. Improvement of reproductive traits such as prolificacy offers a solution to stabilize the decreasing goat population and to meet the nutritional needs of growing human population. In the present study, six novel SNPs in three candidate genes for prolificacy (BMPR1B, BMP15, and GDF9) were genotyped in seven breeds of Indian goats to evaluate their association with litter size. Tetra primer ARMS-PCR and PCR-RFLP based protocols were developed for genotyping six novel SNPs, namely, T(-242)C in BMPR1B; G735A and C808G in BMP15; and C818T, A959C, and G1189A in GDF9 gene. The effect of breed was highly significant (p ≤ 0.01) on litter size but the effect of genotype was nonsignificant. The effect of parity on litter size was also significant in the prolific Black Bengal breed. The litter size differences observed between breeds are attributed to breed differences. Novel mutations observed at different loci in GDF9, BMP15, and BMPR1B genes do not contribute to the reproductive capability of the investigated breeds. Further studies with more number of breeds and animals exploring association of these novel SNPs with reproductive traits may be fruitful.     

Prevalence and serotypes of Salmonella associated with goats at two Australian abattoirs

Aims:  This study was carried out to determine the prevalence and serotype of Salmonella in goats presented for slaughter.
Methods and Results:  A total of 121 goats were examined for the presence of Salmonella in matching rumen, faecal and carcass samples. Samples were analysed for the presence of Salmonella following the Australian Standard AS 1766.2.5-1991. Salmonella was isolated from 56 (46·3%) faecal samples, 55 (45·5%) rumen samples and 35 (28·9%) carcass samples. The dominant serotypes isolated were Salmonella serotype Saintpaul (31%), Salmonella serotype Typhimurium (13%) and Salmonella serotype Chester (11%).
Conclusions:  Salmonella was isolated from at least one of the three sample sites in 68% of animals. Carcase contamination with faeces, compared with rumen liquor, is a greater hazard for Salmonella contamination of goat carcases. Goat meat is a potential source of Salmonella serovars associated with human disease.
Significance and Impact of the Study:  Goat carcases contaminated with Salmonella during slaughter could be a source of food-borne disease if consumed raw or inadequately cooked, or may be a source of cross-contamination to other foods.     

Geographical partitioning of goat diversity in Europe and the Middle East

Thirty microsatellite markers were analysed in 1426 goats from 45 traditional or rare breeds in 15 European and Middle Eastern countries. In all populations inbreeding was indicated by heterozygosity deficiency (mean FIS = 0.10). Genetic differentiation between breeds was moderate with a mean FST value of 0.07, but for most (c. 71%) northern and central European breeds, individuals could be assigned to their breeds with a success rate of more than 80%. Bayesian-based clustering analysis of allele frequencies and multivariate analysis revealed at least four discrete clusters: eastern Mediterranean (Middle East), central Mediterranean, western Mediterranean and central/northern Europe. About 41% of the genetic variability among the breeds could be explained by their geographical origin. A decrease in genetic diversity from the south-east to the north-west was accompanied by an increase in the level of differentiation at the breed level. These observations support the hypothesis that domestic livestock migrated from the Middle East towards western and northern Europe and indicate that breed formation was more systematic in north-central Europe than in the Middle East. We propose that breed differentiation and molecular diversity are independent criteria for conservation.     

A comparison of susceptibility to stocks of Trypanosoma simiae of Glossina pallidipes originating from allopatric populations in Kenya

Abstract. A colony of Glossina pallidipes which originated from Nguruman, Rift Valley Province, Kenya, was significantly more susceptible than a colony of the same species which originated from Shimba Hills, Coast Province, Kenya, to infection with a stock of Trypanosoma simiae CP 11 isolated from wild G. austeni in Coast Province, Kenya, irrespective of whether pigs or goats were used as infecting hosts. Male G. pallidipes from both the colonies were more susceptible than females to this T. simiae stock. Similarly, a G. pallidipes colony of Nguruman origin was significantly more susceptible than the colony of Shimba Hills origin to infection with another stock of T. simiae CP 813 isolated from wild G. pallidipes in Coast Province, Kenya, again irrespective of whether pigs or goats were used as infecting hosts. The susceptibility of the sexes of G. pallidipes from both the colonies to T. simiae CP 813 did not differ significantly when pigs were used as infecting hosts, but male G. pallidipes from both the colonies were significantly more susceptible than female tsetse to this T. simiae stock when goats were used as infecting hosts. Nevertheless, if the observed differences in susceptibility of the two G. pallidipes colonies reflect transmission of trypanosomes by the two allopatric populations of tsetse in the field, then the epidemiology of simiae- trypanosomiasis probably differs between these two areas of Kenya.     

Comparative study on the infection rates of different laboratory strains of Glossina species by Trypanosoma congolense

Teneral Glossina morsitans centralis Machado, G.austeni Newstead, G.palpalis palpalis Robineau-Desvoidy, G.p.gambiensis Vanderplank, G.fuscipes fuscipes Newstead, G.tachinoides Westwood and G.brevipalpis Newstead, from laboratory-bred colonies, were fed at the same time on the flanks of ten goats infected with Trypanosoma congolense Broden isolated in Tanzania or in Nigeria. The seven tsetse species were infected over the range 0.3-49.2%. Survival of both T.congolense isolates was best in G.m.centralis, poorest in G.austeni and the four palpalis group tsetse, with G.brevipalpis intermediate. It is suggested that there are differences in the gut of different laboratory-bred cultures of Glossina Westwood species and subspecies such that T.congolense parasites can survive better in the gut of some than in others and undergo cyclical development to metacyclics in the hypopharynx.     

Leaf miners on Ochna ciliata (Ochnaceae) growing on Aldabra Atoll: patterns of herbivory in relation to goat browsing and exposure to the sun

Abstract.

• 1 The patterns of herbivory by leaf miners on the shrub Ochna ciliata growing on Aldabra Atoll were studied in relation to browsing by feral goats and exposure to the tropical sun versus shading.
• 2 Damage due to both tunnelling (Diptera) and ‘blotch-making’ (Lepidoptera) leaf miners was statistically greater on trees that had been browsed and on those that received more extensive exposure to the sun.
• 3 Effects of exposure and browsing were additive, as evidenced by the lack of statistical interaction between these factors.
• 4 There was a significant negative correlation between the numbers of tunnelling and blotch-making miners in trees that had been browsed, but not in unbrowsed trees.
• 5 Three geographical areas were sampled to test whether the effects of browsing on leaf mining were invariant or influenced by as yet unknown environmental factors. A statistically significant interaction between browsing and geographical region indicated that, while browsed trees had significantly more mines whatever the habitat, the extent of this effect differed across the habitats.

     

Dairy goat kids fed liquid diets in substitution of goat milk and slaughtered at different ages: an economic viability analysis using Monte Carlo techniques

The aim of this study was to analyze the economic viability of producing dairy goat kids fed liquid diets in alternative of goat milk and slaughtered at two different ages. Forty-eight male newborn Saanen and Alpine kids were selected and allocated to four groups using a completely randomized factorial design: goat milk (GM), cow milk (CM), commercial milk replacer (CMR) and fermented cow colostrum (FC). Each group was then divided into two groups: slaughter at 60 and 90 days of age. The animals received Tifton hay and concentrate ad libitum. The values of total costs of liquid and solid feed plus labor, income and average gross margin were calculated. The data were then analyzed using the Monte Carlo techniques with the @Risk 5.5 software, with 1000 iterations of the variables being studied through the model. The kids fed GM and CMR generated negative profitability values when slaughtered at 60 days (US$ −16.4 and US$ −2.17, respectively) and also at 90 days (US$ −30.8 and US$ −0.18, respectively). The risk analysis showed that there is a 98% probability that profitability would be negative when GM is used. In this regard, CM and FC presented low risk when the kids were slaughtered at 60 days (8.5% and 21.2%, respectively) and an even lower risk when animals were slaughtered at 90 days (5.2% and 3.8%, respectively). The kids fed CM and slaughtered at 90 days presented the highest average gross income (US$ 67.88) and also average gross margin (US$ 18.43/animal). For the 60-day rearing regime to be economically viable, the CMR cost should not exceed 11.47% of the animal-selling price. This implies that the replacer cannot cost more than US$ 0.39 and 0.43/kg for the 60- and 90-day feeding regimes, respectively. The sensitivity analysis showed that the variables with the greatest impact on the final model’s results were animal selling price, liquid diet cost, final weight at slaughter and labor. In conclusion, the production of male dairy goat kids can be economically viable when the kids diet consists mainly of either cow milk or fermented colostrum, especially when kids are slaughtered at 90 days of age.     

基于宏基因组研究植物乳酸菌或博落回提取物对山羊回肠微生物合成维生素B12的影响

【目的】探索研究反刍动物胃肠道微生物合成维生素B₁₂的方法,并评估植物乳酸菌或博落回提取物对断奶山羊回肠食靡微生物合成维生素B₁₂的影响。【方法】选取体重相近年龄相仿的断奶黑山羊20只,随机分为对照组(CON, n=7)、乳酸菌组(LAC, n=7)和博落回组(MAC, n=6)。CON组饲喂普通的日粮,LAC组饲喂基础日粮+10 g/d的植物乳酸菌(Lactobacillus plantarum P-8 strains, 4.0×10⁹ CFU/g),MAC组饲喂基础日粮+0.3 g/d的博落回提取物(Macleaya cordata 3.75%)。试验结束后,采集回肠中段食靡样品。利用宏基因组测序技术,比对最新功能基因数据库VB12Path和公共数据库KEGG,分析植物乳酸菌和博落回提取物对山羊回肠食靡微生物合成维生素B₁₂的影响。【结果】结果显示,比对VB12Path数据库共注释到55个与维生素B₁₂合成相关的基因。与CON组相比,LAC组和MAC组中合成维生素B₁₂基因的丰富度和均匀度降低(P<0.05）。3组间基因的β多样性也有显著的差异(P<0.05);比对KEGG数据库共注释到49个与维生素B₁₂合成相关的基因,LAC组的多样性与CON组没有差异,但MAC组的α多样性显著降低(P<0.05)。值得注意的是,比对VB12Path数据库和KEGG数据库均发现LAC组和MAC组中参与前咕啉2合成途径、参与无氧合成途径、有氧合成途径、参与重排转换途径以及腺苷钴胺素合成途径的部分基因(gltX、cbiT、cobT和btuD等)的丰度均显著地高于CON组(P<0.05)。【结论】2个数据库比对后的相似结果表明博落回提取物在对断奶山羊回肠微生物合成维生素B₁₂相关代谢上与植物乳酸菌的作用相似,均可以通过改变其多样性和提高部分关键基因的丰度,从而影响微生物合成维生素B₁₂的潜能,为后期博落回提取物和植物乳酸菌在畜牧养殖中的运用提供一定的理论支撑。此外,2个数据库比对的差异提示未来研究胃肠道微生物维生素B₁₂相关代谢时,应用多个数据库比对,能更全面精确地进行评价,为后期分析过程奠定研究基础和提供新的思路。     

Estimates of (co)variance components due to direct and maternal effects for body weights in Jamunapari goats

Estimates of (co)variance components were obtained for weights at birth, weaning and at 6, 9 and 12 months of age in Jamunapari goats maintained at the Central Institute for Research on Goats, Makhdoom, Mathura, India, over a period of 23 years (1982 to 2004). Records of 4301 kids descended from 204 sires and 1233 does were used in the study. Analyses were carried out by restricted maximum likelihood (REML), fitting an animal model and ignoring or including maternal genetic or permanent environmental effects. Six different animal models were fitted for all traits. The best model was chosen after testing the improvement of the log-likelihood values. Direct heritability estimates were inflated substantially for all traits when maternal effects were ignored. Heritability estimates for weights at birth, weaning and at 6, 9 and 12 months of age were 0.12, 0.18, 0.13, 0.17 and 0.21, respectively. Maternal heritability of body weight declined from 0.19 at birth to 0.08 at weaning and was near zero and not significant thereafter. Estimates of the fraction of variance due to maternal permanent environmental effects were 0.09, 0.13 and 0.10 for body weights at weaning, 6 months and 9 months of age, respectively. Results suggest that maternal additive effects were important only in the early stages of growth, whereas a permanent environmental maternal effect existed from weaning to 9 months of age. These results indicate that modest rates of genetic progress appear possible for all weights.