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1.
In order to predict the body weight of grass cutters from linear body measurements, the weights and measurements of 50 intensively managed female grass cutters aged 5 months were fitted into linear, quadratic and cubic regression models. Highly significant (p?<?0.01) R 2 values ranging from 74 to 98 % were obtained indicating that all body measurements were good predictors of body weight. Although quadratic and cubic models gave slightly higher R 2 values than linear models, it is recommended that farmers should use a simple linear equation based on tail length or heart girth to predict the body weight of their grass cutters. The recommended equations are (weight in kg)?=?0.47?+?0.08 (tail length in cm) and (weight in kg)?=?0.32?+?0.07 (heart girth in cm).  相似文献   

2.
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   

3.
The objective of this study was to determine the usefulness of some linear body measurements in predicting live weight in indigenous Tswana goats at various ages. Data for this study were obtained from 2,783 goats sampled from six agricultural regions of Botswana except for Tsabong and Ghanzi districts. Fifteen farmers keeping goats were randomly selected from each district and records taken on a random sample of 4–12 animals per farm depending on the 1999 Botswana Government average district flock size. Body measurements recorded were heart girth, height at withers, body length, shoulder width, and live weight. Information on age of each animal was estimated from dentition; flock size and sex of the animal were also recorded for each farm. Regression analysis using stepwise selection method in Statistical Analysis System was used to determine prediction equations for live weight with heart girth, height at withers, body length, and shoulder width as independent variables for male and female goats of different ages. In all models, heart girth contributed most in explaining variation in body weight as shown by high partial R 2 which ranged from 0.48 for female mature to 0.80 for mature male goats. Using mean square error, R 2, and Mallows’ C(p), the best prediction equations were for female and male kids (R 2 = 0.83 and 0.82, respectively) and mature male goats (R 2 = 0.82). The poorest model was for mature female goats with R 2 = 0.57. Live body weight could be estimated with accuracy from linear body measurements in Tswana goats which are unique for each sex and age. More research is required to explore using these models to develop measuring tapes for use by resource poor farmers who keep indigenous Tswana goats.  相似文献   

4.
The relationships between live weight and eight body measurements of West African Dwarf (WAD) goats were studied using 211 animals under farm condition. The animals were categorized based on age and sex. Data obtained on height at withers (HW), heart girth (HG), body length (BL), head length (HL), and length of hindquarter (LHQ) were fitted into simple linear, allometric, and multiple-regression models to predict live weight from the body measurements according to age group and sex. Results showed that live weight, HG, BL, LHQ, HL, and HW increased with the age of the animals. In multiple-regression model, HG and HL best fit the model for goat kids; HG, HW, and HL for goat aged 13–24 months; while HG, LHQ, HW, and HL best fit the model for goats aged 25–36 months. Coefficients of determination (R 2) values for linear and allometric models for predicting the live weight of WAD goat increased with age in all the body measurements, with HG being the most satisfactory single measurement in predicting the live weight of WAD goat. Sex had significant influence on the model with R 2 values consistently higher in females except the models for LHQ and HW.  相似文献   

5.
The accurate estimation of livestock weights is important for many aspects of livestock management including nutrition, production and appropriate dosing of pharmaceuticals. Subtherapeutic dosing has been shown to accelerate pathogen resistance which can have subsequent widespread impacts. There are a number of published models for the prediction of live weight from morphometric measurements of cattle, but many of these models use measurements difficult to gather and include complicated age, size and gender stratification. In this paper, we use data from the Infectious Diseases of East Africa calf cohort study and additional data collected at local markets in western Kenya to develop a simple model based on heart girth circumference to predict live weight of east African shorthorn zebu (SHZ) cattle. SHZ cattle are widespread throughout eastern and southern Africa and are economically important multipurpose animals. We demonstrate model accuracy by splitting the data into training and validation subsets and comparing fitted and predicted values. The final model is weight0.262?=?0.95?+?0.022 × girth which has an R 2 value of 0.98 and 95 % prediction intervals that fall within the ±20 % body weight error band regarded as acceptable when dosing livestock. This model provides a highly reliable and accurate method for predicting weights of SHZ cattle using a single heart girth measurement which can be easily obtained with a tape measure in the field setting.  相似文献   

6.
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 México. 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 = β o × (thoracic circumference)β1. Model 2: Live weight = β o × (height to the withers) βl × (thoracic circumference) β2. 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 × (thoracic circumference)1.84107 (R 2 = 0.9839). Females: live weight = 0.031255 × (thoracic circumference)1.72888 (R 2 = 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 México because they overestimated the live weight.  相似文献   

7.

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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8.
河南小尾寒羊体尺与体重的相关性分析   总被引：3，自引：1，他引：2  
为探讨河南小尾寒羊体尺指标与体重的相关性,更好的服务于选种、选育工作,作者运用SPSS软件对98只河南小尾寒羊的体尺、体重进行了相关分析和通径分析,并建立了最优回归方程。结果表明,河南小尾寒羊的体重（〖AKY-〗）与体高（X1）、体长（X2）、胸围（X3）、胸宽（X4）、胸深（X5）、尾宽（X6）、尾长（X7）呈极显著正相关（P＜0.01）;体长、胸围、胸宽和胸深4个指标对体重的直接作用和间接作用都极大;得到最优回归方程为：〖AKY-〗=0.226X2＋0.535X3＋0.200X4。  相似文献   

9.
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   

10.
The relationship between weight and body measurements of 227 Alpine ibex Capra ibex (162 males and 65 females, age range: 2-16 years) were analysed by linear and multiple regression. The animals were live-captured across all seasons of the year, in the Western Italian Alps, 1986-1994. The relationship between weight and body measurements changed with sex and season. In male ibex, the best annual estimation of the body weight was obtained using as predictor variables the squared value of the chest girth and age. In females, the best predictive variables were age, total body length and withers height. Age was always selected as a predictor variable, when considered in the prediction models. The use of chest girth and the squared value of the chest girth as predictive variables in the regression equation, being the most highly correlated linear measurements with total weight, did not result in an accurate prediction of ibex body weight. The best prediction was obtained using age and different linear measurements in stepwise multiple regression, nevertheless the standard error of the estimate and the magnitude of the 95% prediction interval were great. The use of linear measurements cannot be considered accurate nor precise predictors of body weight in Alpine ibex.  相似文献   

11.
The objective of this study was to use body measurements taken at birth to predict mature weight (MW) and maturing rate (MR) of mature cows. Measurements for length of rear leg from hook to dewclaw (LL), circumference of forearm (FA), heart girth circumference, body length from point of shoulder to pin bone (BL), width at loin (WL), width at hip, and depth at chest (DC) were taken within 24 h of birth on 131 purebred female Angus calves and 39 purebred Charolais female calves in 1992, 1993, and 1994. Fifty-four Angus and 20 Charolais cavles were available for estimates of MW and MR. Stepwise regression determined which traits would be significant predictors of MW and MR. Early BW or ADG (for various intervals up to 1 yr of age) were also included in some models. Stepwise regression, including the seven body measurements, resulted in the following equations: MW = −230.12 + 22.54 (LL) +16.38 (FA) + 1.12 (BL) + 30.61 (WL) − 21.66 (DC) and MR = 0.10018 − 0.00038 (BL). The R2 values were 0.46 and 0.29, respectively. Including early BW or ADG in models for MW did not result in higher R2 values, although models with fewer traits included were obtained. Results of this study indicate that body measurements taken at birth may be useful in predicting MW and MR of cows.  相似文献   

12.
本研究对30只94日龄中畜小型白羽肉鸭(CMD)在大群地面散养方式下的屠宰性能和体尺指标进行了测定,并对测定结果进行了相关分析,结果发现活重与体斜长、龙骨长、胸宽、胫围、半潜水长等体尺指标的相关系数分别达到0.588、0.660、0.618、0.654、0.582,均达到极显著水平(P<0.01);全净膛重与体斜长、龙骨长、胫围、半潜水长等体尺指标的相关系数分别达到0.476、0.566、0.552、0.455,均达到显著(P<0.05)或极显著水平(P<0.01)。此外,研究分别建立了活重与体斜长、龙骨长、胸宽、胫围、半潜水长以及全净膛重与体斜长、龙骨长、胫围、半潜水长的回归模型,两个回归模型经F检验均达到显著水平(P<0.05)。  相似文献   

13.
Twenty-four nonlactating and nonpregnant Belgian Blue double-muscled cows, with diverging parities (one to seven), body conditions and body weights (436 to 903 kg), were used to investigate empty body (EB) composition. Direct measurements of EB composition, such as water, fat, protein, ash and energy, were carried out after slaughter. EB weight (EBW) averaged 624.7 kg and consisted of 393.3 kg water, 122.3 kg protein, 84.5 kg fat and 24.6 kg ash and was characterized by an energy content of 6158 MJ. Relationships between body weight (BW), body condition score (BCS), chest girth, dressing percentage, carcass grading score, EBW, rib-cut components and EB composition were determined. Significant regression equations (P<0.001) with a coefficient of determination (R2) of more than 0.9 were obtained between BW or BW and BCS and EB water, EB fat and EB energy. The prediction of EB ash was less accurate (R2<0.75). The relationship could further be improved by inclusion of carcass characteristics and rib-cut components (R2>0.95). Energy contents of EB lipids and protein amounted to 39.3 and 23.2 MJ/kg. EB protein (197 g/kg) was higher in the present double-muscled cows than reported for non-double-muscled animals, while EB fat (126 g/kg) and EB energy (9.5 MJ/kg) were lower. One BCS unit corresponded with 26.7 kg EB fat (P<0.001; R2=0.659). It can be concluded that simple live animal measurements as BW and BCS can be considered as potentially useful predictors of EB composition in double-muscled cows. Theoretical calculations based on the present observed data indicated that body reserves were lower in Belgian Blue double-muscled cows than in most other breeds. Body reserve tissue may be limited in young primiparous suckling cows so that energy restriction may be detrimental for reproductive performance.  相似文献   

14.
This paper investigated estimation methods: least squares method, M-estimation, Theil method, Least Absolute Deviation method to estimate the parameters of simple regression model in situation that the underlying assumptions of least squares estimation are untenable because of outliers. To compare these methods, the effect of chest girth on body weights of German Farm × Hair crossbred kids at weaning period was examined. Chest girth of kids is independent variable and body weight at weaning period is dependent variable in the model. Mean square error and R2 value are used to evaluate estimator performance. Because two observation values are outliers and the model estimated from this method have minimum mean square error and maximum R2 value for different sample sizes (n = 10, 20, 30 or 50), M-estimation method is proposed to predict the parameters of the model.  相似文献   

15.
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16.
最小二乘法在黄牛体重估测中的应用   总被引：4，自引：0，他引：4  
本文能过最小二乘法用黄牛的体长、胸围两项体尺估测黄牛的体重。不同的估测方法估测的精度不同,采用体长和胸围两项体尺建立在二元二次回归方程估测的体重Ｙ１与实测的体重Ｙ０的相关系数最高（ｒ０１为０．６７０５）;用体长Ｘ１的单项体尺估测的体重Ｙ２与实际体重Ｙ０相关系数（ｒ０２）为０．６１４;用胸围Ｘ２的单项体尺估测的体重Ｙ３与实测体重Ｙ０的相关系数（ｒ０３）为０．６２６;用体长Ｘ２建立二元一次回归方程估测  相似文献   

17.
本研究旨在探讨兰州大尾羊×小尾寒羊F1代羔羊体重和体尺的相关关系,为通过体尺性状估计其体重提供科学的理论依据。试验随机选取80只150日龄兰小杂交F1代羔羊,公、母羔各半,测量其体重（Y）、体长（X1）、体高（X2）、胸围（X3）、管围（X4）、胸深（X5）和胸宽（X6）,运用SPSS 22.0软件分别对公、母羔的体重和体尺数据进行相关性分析、通径分析、逐步线性回归分析和相关系数的分解。结果表明,兰小杂交F1代羔羊的体重与体长、体高、胸围、管围、胸深、胸宽均呈极显著正相关（P<0.01）,公、母羔胸围与体重的相关程度最高,相关系数分别为0.907和0.908,其次为体长,相关系数分别为0.875、0.844。各体尺性状间也呈极显著正相关（P<0.01）,其中胸围和体长的相关系数最高。胸围和体长主要通过直接作用影响体重,胸深、管围、体高、胸宽主要通过间接作用影响体重,胸围对体重的直接作用最大,胸深对体重的间接作用最大。公、母羔体重与体尺的最优回归方程分别为：Y=-43.861+0.675X3+0.394X1（r=0.945,P<0.01）和Y=-38.378+0.590X3+0.397X1（r=0.948,P<0.01）。综上所述,胸围和体长是影响兰小杂交F1代羔羊体重的两个重要因素,在该品种的选育和肥羔的生产过程中,要加强对胸围和体长的选择力度,同时考虑胸深、管围、体高、胸宽的影响。  相似文献   

18.
Our aim was to ascertain inbreeding depression in the Spanish Purebred horses for eight body measurements. A total of 16,472 individuals were measured for height at withers, height at chest, leg length, body length, width of chest, heart girth circumference, knee perimeter and cannon bone circumference. Three different multivariate animal models including, respectively, no measure of inbreeding, individual inbreeding coefficients (Fi) or individual increase in inbreeding coefficients (ΔFi) as linear covariates were used. Significant inbreeding depression was assessed. Even though the models including measures of inbreeding fitted better with data, no effect on estimates of genetic parameters was assessed. However, the inclusion of inbreeding measures affected the ranking order according to the Expected Breeding Values (EBV). Due to the better fit with data and nice properties (the adjustment of individual inbreeding coefficients with the pedigree depth and linear behaviour) the use of ΔFi in the evaluation models can be recommended for morphological traits in horses.  相似文献   

19.
引进贾洛羊种公羊杂交改良甘加羊,贾甘F1平均初生重4.05kg、0～6月龄平均日增重132.55g/d,显著高于甘加羊的相应指标,差异极显著(P<0.01)。3、6、18月龄贾甘F1的体重增加明显,差异极显著(P<0.01);体高、体长、胸围、管围均高于甘加羊,杂交优势明显,经济效益显著。  相似文献   

20.
[目的]解析白羽王鸽屠宰性能与体尺性状的关联性,为今后在贵州地区科学系统地培养白羽王鸽积累参考数据。[方法]对30日龄白羽王鸽的体尺和屠宰性能指标进行了测定,并对测定指标进行显著性检验和相关性分析。[结果]白羽王鸽在30日龄时具有较高的屠宰率（87.200%）,平均活重（429.960±51.781）g,全净膛重（319.253±40.342）g,全净膛率74.610%,具有较好的肉用性能。白羽王鸽屠宰性能和体尺性状的相关分析结果显示,白羽王鸽胫长、活重和屠宰重与体斜长具有显著（P<0.05）相关性,翅重与体斜长极显著（P<0.01）相关;龙骨长与胸深、胸宽、全净膛重、胸肌重呈现极显著（P<0.01）正相关;胸深与胸宽极显著（P<0.01）正相关,与胫围极显著（P<0.01）负相关,与活重、屠宰重、胸肌重和腿肌重呈现显著（P<0.05）正相关;屠宰重、全净膛重、胸肌重、腿肌重、头重和翅重与活重呈现极显著（P<0.01）正相关;全净膛重、胸肌重、腿肌重、头重、翅重与屠宰重呈现极显著（P<0.01）正相关。该研究设立了白羽王鸽屠宰性能与体尺性状之间的多元回归方程,同时对白羽王鸽活重、屠宰重、全净膛重、胸肌重和腿肌重与体斜长、龙骨长、胫长和胫围分别建立了回归模型,模型拟合度F检验均达显著或极显著水平。[结论]以上研究结果可为白羽王鸽的相关研究提供参考。  相似文献   

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