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1.
The majority of Tswana sheep and goats in Botswana are indigenous. These animals provide income, employment and food security to the resource-poor farmers. Limited characterization of these species has been done, resulting in poor efforts to fully exploit and conserve them. The objective of this study was to phenotyically characterize indigenous sheep and goats countrywide. Measurements were collected from 2783 goats and 1282 sheep kept by traditional farmers, covering nearly all the districts of Botswana. In each district a total of 15 farmers with sheep and goats were selected randomly and records were taken on 4-12 animals per farm, depending on average district flock size. Traits recorded for each animal were body length, body weight, ear length, heart girth, height at withers, hip width, neck length, rump height, shoulder width, tail length (goats only) and horn length. Age (estimated from dentition) and sex of the animals were also recorded and vegetation type was noted. The data were analysed using the general linear model procedure in Statistical Analysis System. Prior to analyses, a main effects model of sex, age and vegetation type was fitted. Later, two types of analyses were done: (i) within a vegetation type fitting sex and age and their interaction, and (ii) within sex fitting age and vegetation type and their interaction. Least-squares means were separated using Student's t-test. Sex, age and vegetation significantly (p<0.05) affected the magnitude of traits. Phenotypic body measurements of castrates were generally higher than in both females and entire males, which were similar. The body measurements of younger animals were less than those of older age groups since the former were still growing compared to the latter. Different vegetation types promoted different body measurements, which should be expected due to differences in nutrient supply from different vegetation types. The indigenous breeds of sheep and goats can be classified as medium-size breeds. The breeds should be conserved since they are well suited to the harsh environment of Botswana where drought and livestock diseases are ever present. Efforts should be undertaken to characterize them genetically and increase their productivity.  相似文献   

2.
A survey of pastoralist and agropastoralist households in south-east Kenya was conducted to determine their production objectives and management strategies in order to optimize and extend a breeding programme for indigenous small East African Shorthorn Zebu cattle. The reasons for keeping cattle and the breed/trait preferences identified reflect the multiple objectives of the livestock keepers, with both adaptive traits and productive/reproductive traits rated as important. Although the Maasai and Kamba zebu (M&KZ) breeds were ranked highly with regard to adaptive traits, the population is considered to have been in decline over recent years. In order to promote the conservation and sustainable use of the M&KZ cattle, the formation of an open nucleus breeding scheme is recommended. In particular, such a scheme would be able to address several existing constraints (e.g. individual herds are very small and communal use of pastures/water makes controlled mating difficult). Such interventions would require the full participation of the livestock keepers, as well as ensuring that a holistic approach to species and breed attributes is taken into account in setting breeding goals, such that the full array of contributions that livestock make to livelihoods and the genetic characteristics related to these contributions are fully incorporated into the programme.  相似文献   

3.

This study was carried out in order to identify the body measurements of two different Dromedary camel breeds raised in Algeria. The animal material of the study consisted of a total of 115 animals belong to Steppe (n?=?55) and Sahraoui (n?=?60) camel breeds. Eye and coat colors along with body measurements such as head length, neck length, neck girth, tail length, distance between eyes, distance between ears, body length, withers height, chest girth, and live weight were determined. Least squares means for head length, neck length, neck girth, tail length, distance between eyes, distance between ears, body length, withers height, chest girth, and live weight are found 48.2, 116.9, 65.7, 55.6, 24.1, 22.5, 152.2, 184.5, 141.2 cm, and 217.2 kg for Steppe and 48.1, 101.2, 56.2, 51.2, 23.4, 18.3, 135.6, 167.3, 176.8 cm, and 298.9 kg for Sahraoui camel breeds, respectively. The distribution of brown and black eye colors for the Steppe camel breed is as 58.2% and 41.8%, respectively, while all of the Sahraoui camels studied had a brown eye color. The proportional distribution in terms of body color included are coffee, dark coffee, and red colors for 1.8%, 83.6%, and 14.6% in the Steppe camel and 98.3%, 1.7%, and 0.0% for the Sahraoui camel, respectively. As a result, this study concluded that the withers height and chest girth could estimate the body weight in the two breeds of camels with different ages.

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4.
探讨微卫星作为地方山羊品种生长性状的遗传标记   总被引：1，自引：2，他引：1  
采用微卫星技术及最小二乘拟合线性模型，利用崂山奶山羊、济宁青山羊、鲁北白山羊和莱芜黑山羊4个地方山羊品种中的10个多态性微卫星基因座，分析了微卫星基因座及其等位基因对山羊生长性状的关联效应。结果表明：与品种、性别和年龄等因子比较，标记因子对山羊体重和体尺性状的影响较小，但发现BM6404、BM1818、BM812和BM6444基因座对体重有显著影响（P〈0．05或P〈0．01），BM6404、BM1818、BMS12484、MAF70基因座对主要体尺性状有显著影响（P〈0．05或P〈O．01）。BM6404基因座的等位基因130可能对山羊的胸围、体高、尻宽均有正效应；120对胸围有较强的负效应，而对体高、尻长则有较强的正效应；168对尻长、尻宽均表现为负效应。MAF70基因座的等位基因142对体长有正效应，178对体长有负效应。BMS1248基因座的等位基因128对管围有正效应。  相似文献   

5.
Meat production is the most important trait in the breeding objectives of sheep production in East Africa. The aim of this study was to investigate breed differences in live weight, conformation, carcass traits and economic values for meat production among Red Maasai and Dorper sheep and their crosses. In total, 88 ram lambs, which were reared at the ILRI experimental station, Kapiti plains Estate in Central Kenya, were used for the study. The lambs were slaughtered at Kenya Meat Commission (KMC) at about 1 year of age. Prior to slaughter, the lambs were weighed, measured and assessed by experienced evaluators, and at the abattoir carcass traits were recorded. Large breed differences were found for most traits. Dorper lambs were heavier at delivery for slaughter and had better carcass grade but lower dressing percentage and fat levels than Red Maasai. Crossbreds were generally better than the parental breeds. Evaluators were willing to pay more for the Dorper lambs for slaughter although carcass weights later were shown not to be higher than for Red Maasai. Evaluators undervalued Red Maasai lambs by 8–13 % compared to Dorper lambs according to the prices quoted per kilogramme live or carcass weight by KMC. Live weight was better than any other live measure in predicting carcass weight. Due to the overall higher ranking of the crossbred lambs for meat production, Dorper may be useful as a terminal sire breed for crossing with Red Maasai ewes.  相似文献   

6.
为估计鲁中肉羊初生重、体高、体长、胸宽、胸深、胸围和管围的遗传参数,利用2018年上半年出生的611只鲁中肉羊的初生体尺体重数据,采用AI-REML (Average information restricted maximum likelihood)算法,借助DMU软件分析以产羔数为固定效应、个体加性遗传效应为随机效应的多性状动物模型。结果表明:鲁中肉羊初生重、胸宽、胸深、体高、体长、胸围和管围的遗传力分别为0.16、0.10、0.22、0.44、0.43、0.46和0.52,各性状之间遗传相关为-0.517～0.773,表型相关为-0.197～0.503。说明鲁中肉羊初生重、胸宽和胸深为低遗传力性状,体高、体长、胸围和管围为中等遗传力性状。  相似文献   

7.
为了比较道赛特羊、特克塞尔羊及小尾寒羊的生长发育性能和适应性,试验对3品种羊的初生重、断奶重、体高、体重、体长、胸围、管围等生长发育指标进行测定分析,育肥后进行屠宰测定。结果表明,2个引进品种间初生重和断奶重无显著差异,且均表现出早期生长发育快的特点,其体高、体重等生长发育指标及屠宰性状均高于小尾寒羊,表现出良好的肉用效果和适应性。育肥后无角道赛特羊、特克塞尔羊胴体重、腰肌重、大腿重和眼肌面积显著高于小尾寒羊(P0.05)。  相似文献   

8.
The relationships between live weight and eight body measurements of West African Dwarf (WAD) sheep were studied using 210 animals under on farm condition. Data obtained on height at withers (HW), heart girth (HG), body length (BL), head length (HL), head width (HDW), loin girth (LG), length of hindquarter (LHQ) and width of hindquarter (WHQ) were fitted into linear, allometric and multiple regression models to predict live weight from the body measurements. Results revealed that body measurements of WAD sheep were generally higher in the rams than in the ewes. Coefficient of determination (R(2)) values computed for the body measurements were generally higher (0.87-0.99) using allometric regression model than linear regression model (0.44-0.94). Heart girth (HG) and WHQ depicted the highest relationship to live weight in linear and allometric models compared to other body measurements. Based on stepwise elimination procedure, HG, HL and WHQ were better in predicting live weight in multiple linear regression models. The magnitude of correlation coefficient (r) indicate that WHQ shows the highest correlation with live weight (r = 0.96) compared to HG (r = 0.94).  相似文献   

9.
The characterisation of the small ruminant populations in developing countries will play a major role in the maintenance of the genetic resources as the basis for future improvement in livestock production. The present study aimed at morphological characterisation of the two main breeds of sheep in Ghana by assessing variation within and between breed populations using principal component and discriminant analyses. The two breeds were the Sahel and the Djallonke sheep of both sexes and of two groups namely, young (1 year old, consisting of 74 animals) and mature sheep (≥2 years old, comprising 219 animals). The analysis of variance revealed significant (P?<?0.05) differences in the morphological traits of the Sahel and the Djallonke sheep breeds with higher values recorded for the former. Sexual dimorphism was in favour of male animals in all the morphological traits examined. Mature animals also had comparative advantage over the young. Two principal components were extracted to discern the structure of the two genetic groups. The most discriminating traits between the two sheep breeds were rump height, height at withers, neck girth and pin-bone width. Mahalanobis distance between the two genetic groups was 5.723 (P?<?0.0001). The developed discriminant functions clearly discriminated and classified the Sahel and the Djallonke sheep into their breeds of origin, thus yielding 100, 93.4 and 90.4 % accurate classification for the rams, ewes and the overall sheep population, respectively. The present approach would greatly help in establishing management and conservation policies for the sustainable production of the two Ghanaian sheep breeds.  相似文献   

10.
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11.
The goal of this research, conducted in the most southern part of Taiwan, was to create a new genotype: the "Hengchun Black Goat" (HB). Nubian (NU) goats were first crossed with a local breed, the Taiwan native (TN), then the F1 females were crossed with the imported black Boer (BO) bucks. The upgraded genotypes were then compared with the parental breeds and Kinmen (KM), another local breed, for growth traits and body conformation. The study concerned 1,136 kids born between 2005 and 2007. The analysed traits were body weight (BW), average daily gain and three linear measurements, namely height at withers, body length and chest girth. The results indicated that environmental factors, sex, birth and rearing type, dam parity and birth year had significant effects from birth to 6 months of age. The same differences persisted to 1 year. At 6 months of age, the least square means of BW were 16.2, 19.2, 25.1, 32.0, 23.9, 23.8, 23.0 and 23.9 kg, for KM, TN, NU, 1/2BO, 3/4BO, 7/8BO, BO and HB, respectively. These first results also indicate that the growth performances of the newly created line, Hengchun Black, were equivalent to those of Boer goats.  相似文献   

12.
试验旨在研究青年伊犁马不同运动性能间步幅指数与步频指数的差异,并探究其与运动性能的关联性,以期提高伊犁马个体选择和性能测定的科学性和准确性。试验以参加伊犁马常态化赛事的72匹2岁伊犁马为研究对象,测量其体尺与步态特征,计算其各项步幅指数与步频指数,分析不同途程、不同运动性能间的差异,并对各指标与竞赛用时做偏相关分析,探究各指标与运动性能的关联性。结果表明,伊犁马1 600 m竞赛中,精英组体高步频指数、体长步频指数均极显著高于普通组（P<0.01）,且与竞赛用时呈极显著负相关（P<0.01）,精英组体高双支撑相步幅指数、体长双支撑相步幅指数、体高步幅指数、体长步幅指数均极显著高于普通组（P<0.01）,并与竞赛用时呈极显著负相关（P<0.01）;3 600 m竞赛中,精英组体高步频指数、体长步频指数极显著高于普通组（P<0.01）,体长步频指数与竞赛用时呈极显著负相关（P<0.01）,精英组体高双支撑相步幅指数,体长双支撑相步幅指数均显著高于普通组（P<0.05）,且与竞赛用时呈显著负相关（P<0.05）。体高步频指数与体长步频指数可作为青年伊犁马的首选性能评估和选择指标,可广泛用于青年伊犁马育种和训练实践中,以提高性能评估效率。  相似文献   

13.
OBJECTIVE: To compare pathologic changes of the horizontal ear canal associated with chronic severe otitis externa between Cocker Spaniels and dogs of other breeds. DESIGN: Retrospective study. ANIMALS: 80 dogs with severe otitis externa that required total ear canal ablation with lateral bulla osteotomy. PROCEDURE: Medical records were reviewed for breed, sex, and age at time of surgery. Histologic specimens from the horizontal ear canal were evaluated by a single examiner for overall tissue response pattern and scored for sebaceous gland hyperplasia, ceruminous gland hyperplasia, ceruminous gland ectasia, fibrosis, pigment-laden macrophages, and osseous metaplasia. RESULTS: 48 of 80 (60%) dogs were Cocker Spaniels. Thirty-five of 48 (72.9%) Cocker Spaniels had a predominately ceruminous tissue response pattern; only 9 of 32 (28.1 %) dogs of other breeds had the same pattern. Other breeds most commonly had a pattern dominated by fibrosis (n = 13 [40.6%]); fibrosis was the predominant pattern in only 4 of 48 (8.3%) Cocker Spaniels. Discriminant analysis and K-means clustering of 4 histopathologic criteria correctly classified 75% of the dogs as Cocker Spaniels or all other breeds. CONCLUSIONS AND CLINICAL RELEVANCE: Cocker Spaniels are at increased risk for chronic severe otitis externa requiring total ear canal ablation with lateral bulla osteotomy, indicating that earlier and more aggressive management of the primary otitis externa and secondary inflammation is warranted in this breed. Cocker Spaniels with chronic severe otitis externa have distinct differences in pathologic characteristics of the horizontal ear canal, compared with other breeds.  相似文献   

14.
Pelvis size plays an important role to prevent dystocia in cattle caused by the foeto-maternal disproportion in commonly primiparous females. The reproducibility and repeatability are two important aspects for the reliability of the measurements to use in the selection of cattle for culling. Pelvic measures were taken with a Rice pelvimeter from 224 young cattle (180 females and 44 males) of four beef breeds in South Africa. One experienced and two inexperienced observers each measured pelvic height and width twice. The proportion measurements with a maximum difference of 0.5 cm within animal compared with the first measurement by the experienced observer are around 80% and by the inexperienced observers around 50% for pelvic height and around 60% for pelvic width. Breed and sex do not affect the reliability of pelvimetry by an experienced observer. Under- and overestimation of pelvis size were observed in inexperienced observers, which seems to be unrelated to breed and sex.  相似文献   

15.
为探讨公羊体型与精液品质之间的相关性,本文收集了2014—2017年新疆天山畜牧生物技术有限公司种羊示范场精液生产性能与体尺测量记录,应用SPSS 19.0软件分别对萨福克羊和杜泊羊的周岁公羊和成年公羊的数据进行体尺性状和精液品质的相关性分析。结果表明:周岁萨福克公羊精液量与体高、体长、胸围、腹围、尻高、尻长呈极显著正相关;周岁杜泊羊精液密度与睾丸围呈显著正相关,与尻高呈极显著负相关,与体高呈显著负相关;成年萨福克公羊精液量与体高、尻高呈显著正相关;成年杜泊羊精液量与体高、尻长、腰角宽呈显著正相关;精液密度与尻高呈显著正相关。在保证种公羊体质与增重的前提下,适当选择体高、尻长和睾丸围值大的公羊,可增加精液量和精液密度。  相似文献   

16.
Live weight is an important trait in cattle farming. Weighing is not always feasible and therefore live weight is often estimated from easily accessible data. In this study, data on live weight, age and gender, and four body measurements, withers height (WH), heart girth (HG) and width of the shoulders (SW) and hind quarters (BcW) of double-muscled Belgian Blue beef (DM-BBB) farm animals were used to develop multivariable non-linear and linear regression models that predict live weight from these easily accessible data. The relationship between the logarithm of the live weight and the logarithm of time is adequately described by a general logistic function. The age period from 100 to 600 days of age is contained in the linear part of the logistic function. This region is of particular economic interest because it contains the yearling age and slaughter age that are important in DM-BBB breeding and management. Adding one of the body traits in the linear models that contain age and gender as fixed effects decreases the coefficient of variation. A model with withers height and shoulder width has the lowest coefficient of variation, with no further significant improvement when adding either heart girth or width of the hind quarters.  相似文献   

17.
Body measurements (length from nape of neck to the withers; height to withers; length from withers to tail root; length from shoulder to tuber ischii; thoracic circumference; umbilical circumference) were taken and correlated with live weight from 160 donkeys (mean +/- standard deviation = 6 +/- 2.6 years old) in Central Mexico. The age was assessed from dentition. Sex of the donkeys was also recorded. Sex was an important factor of variation (p = 0.011). Live weight was estimated using two allometric models. Model 1: Live weight = beta x (thoracic circumference)beta1. Model 2: Live weight = betao x (height to the withers) beta1 x (thoracic circumference) beta2. Separate prediction equations were produced for males and females, plus one for the total sampled. The 'best fit' models, were those using thoracic circumference to predict the live weight. Males: live weight = 0.018576 x (thoracic circumference)1.84107 (R2 = 0.9839). Females: live weight = 0.031255 x (thoracic circumference)1.72888 (R2 = 0.9839). The equations derived to estimate the live weight of donkeys in Britain, Morocco and Zimbabwe were less satisfactory for use with donkeys from Central Mexico because they overestimated the live weight.  相似文献   

18.
A total of 436 young bulls from fifteen Western European breeds, including beef, dairy and local types from five countries, were studied to assess variability in live weight, live weight gain, body measurements and carcass traits. Animals were logged indoors, and fed a diet based on concentrate and straw offered ad libitum from 9 months of age to slaughter at 15 months of age. The weight, body length, height at withers and pelvis width, of the animals were recorded at 9, 12 and 15 months of age. After slaughter, 15 carcass variables were recorded, including carcass weight, EU classification scores, morphological measurements and dissection data. Data were analysed by GLM, regression and principal component analysis procedures.Significant differences were found between breeds for all variables studied, however, the body size measurements and the carcass traits were more useful to discriminate among cattle breeds, than either live weight or daily gain. With respect to the body size and carcass traits the studied breeds could be grouped as:
– Specialized beef breeds, comprising Piemontese, Asturiana de los Valles, Pirenaica, Limousin, South Devon, Charolais and Aberdeen Angus, all of which were characterized by high muscularity, wide pelvis and medium height and a low to medium level of fatness.
– Local and dairy breeds, comprising Jersey, Casina, Highland, Holstein and Danish Red, the latter two breeds were tall animals, while the former three breeds were small in size. In general the group was poorly muscled and tended to have a high or medium level of fat.
– Intermediate group, Avileña, Marchigiana and Simmental: these breeds were characterized by an intermediate muscle conformation and fatness level and were relatively tall.
This study provides a detailed assessment or a wide range of variables in the major breeds, and several minor breeds, that are used in breeding programmes across Europe and elsewhere, and will provide information that will be of use to define breeding strategies to meet the demands of the European beef market.  相似文献   

19.
This study used discriminant analysis to evaluate body measures and sexual dimorphism in Mangalarga Marchador horses. Discriminant analysis is a multivariate method that generates functions to classify animals using a prior criterion. In this study a prior criterion is male or female. The study analyzed 25 linear and 11 angular measures obtained from 25 stallions and 56 mares registered with the Mangalarga Marchador Brazilian Breeders Association. Knee girth, cannon girth, chest width, chest girth, back-loin length, hip width, distance from elbow to knee, hind limb hoof length, head width, shoulder length, and body length were found to be linear measures that provided evidence of sexual dimorphism. Angular measures with evidence of sexual dimorphism were shoulder–humerus, metacarpal–phalanx, coxae–femur, and femur–tibial angles. Stallions were larger than mares for almost all linear measures, except for back-loin length, hip width, and distance from elbow to knee. Shoulder–humerus and coxal–femur angles were larger in mares, while metacarpal–phalanx and femur–tibial angles were larger in stallions. Using linear measures, two mares were classified as stallions and three stallions were classified as mares. For angular measures, two other mares were classified as stallions and three other stallions were classified as mares. The discriminant functions can be useful for the selection of horses and to avoid registration of animals not meeting the phenotypic standards of the breed association.  相似文献   

20.
The Sahiwal breed has been used for upgrading the East African Zebu (EAZ) for improved milk production and growth performance in the southern rangelands of Kenya. Main users of this breed are Maasai pastoralists. Until now, there has been no deliberate effort to understand why these pastoralists specifically prefer to keep Sahiwal genetic resources as well as which traits are considered important by them and what is the underlying reason for this. However, this information is regarded vital for further development of the breed. A survey was conducted between May and October 2009 among Maasai pastoralists in Kajiado and Narok counties in the Southern part of Kenya, and private ranches and government farms to identify production objectives and breeding goals of Sahiwal cattle producers. Sahiwal genetic resources were mainly kept for domestic milk production and for revenue generation through milk sales and live animals. To a limited extent, they were kept for breeding and also for multiple objectives that included insurance against risks and social functions. Production aims were influenced to varying extents by various household and farmer characteristics. Sahiwal cattle and their crosses were generally perceived to be better with respect to productive traits and fertility traits when compared to the EAZ. However, the EAZ was rated higher with respect to adaptation traits. The breeding objective traits of primary importance were high milk yield and big body size, good reproductive efficiency and relatively good adaptation to local production conditions. Performance and functional traits are important breeding goals that play a major role in fulfilling the multiple production objectives. This forms the basis for the optimisation of a breeding programme for sustainable utilisation to meet the needs of Sahiwal cattle producers.  相似文献   

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