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1.
本文阐述了以30头3岁及3岁以上空怀或怀孕6个月以前中等膘情母牛体重为依变量 y,以体斜长 x_1、胸围 x_2为自变量,利用二元回归原理,对渤海黑牛体重估测公式进行了推导。通过 F 检验(P<0.01)、复相关系数检验(P<0.01)和实践检验,体重估测值与实际平均值仅差2.3千克,每头误差绝对值平均11.03千克,误差率3.26%(P>0.05);较约翰逊估重公式所得6.88%误差率降低3.62%,说明所得回归方程=2.14x_1+3.37x_2-522.09较客观地反映了上述母牛体重的变化规律。然后,对相同年龄范围怀孕6个月以上中等膘情母牛,空怀或怀孕6个月以前的上等、下等膘情母牛及公、阉牛的体重估测公式进行了校正。为便于记忆和实际应用,对所得公式进行了简化。 相似文献
2.
应用二元回归原理推导渤海黑牛体重估测公式 总被引：1，自引：0，他引：1
本文阐述了以30头3岁及3岁以上空怀或怀孕6个月以前中等膘情母牛体重为依变量y,以体斜长x_1、胸围x_2为自变量,利用二元回归原理,对渤海黑牛体重估测公式进行了推导。通过F检验(P>0.01)、复相关系数检验(P<0.01)和实践检验,体重估测值与实际平均值仅差2.3kg,每头误差绝对值平均11.3kg,误差率3.26％(P>0.05);较约翰逊估重公式所得6.88％误差率降低3.62％,说明所得回归方程y=2.14x_1+3.37x_2-522.09较客观地反映了上述母牛体重的变化规律。然后,对相同年龄范围怀孕8个月以上中等膘情母牛空怀或怀孕6个月以前的上等,下等膘情母牛及公、阉牛的体重估测公式进行了校正。为便于记忆和实际应用,对所得公式进行了简化。 相似文献
3.
张树金 《北方牧业(奶牛)》2009,(9):34-35
后备乳用小母牛的饲养成本占奶牛生产总成本的20～25％。25周龄时,保持小母牛健康、获得一致的生长以达到目标的骨架和体重,而体况膘情适宜、饲料成本较低是小母牛养殖场需要考虑的重要因素。 相似文献
4.
随机实测２６１头黎平黄牛的胸围，体斜长和体重，根据体重等于体积乘以密度的原理，采用回归分析方法进行了黎平黄牛体重估测公式的推导与验证。结果表明，黎平黄牛的性别对体尺与体重回归关系的影响差异不显著，合并公母牛的体尺体重数据。得出该品种总的体重估测公式：体重＝胸围＾ｍ）＊体斜长（ｍ）＊８８－８（ｒ＝０．９９７１，Ｓｙ／ｘ＝４．７０１）。胸围，体斜长对体重的回归关系极显著。估测体重的离回归标准误为４．７ 相似文献
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[目的]新疆地区通过引进美国瑞士褐牛导入杂交改良新疆褐牛,以提高新疆褐牛品质和生产性能。研究旨在校正约翰逊估测法中系数,准确估测美新杂交褐牛体重,为今后新疆褐牛选育提高和新类型培育中体重测定提供方法。[方法]试验共测定美新杂交褐牛生产母牛283头,包括体重、体斜长和胸围,通过实测体重与约翰逊法估测体重比较分析,校正约翰逊法公式中系数,再进行验证。[结果]结果表明,美新杂交褐牛实测体重极显著低于约翰逊法估测体重(P0.01),对约翰逊法公式中的系数校正,校正后系数为12 300,即经过校正后的美新杂交褐牛体重约翰逊法估测公式为:体重=胸围~2×体斜长/12300,该公式在50头美新杂交褐牛进行验证,实测体重与估测体重差异不显著(P0.05),说明校正系数后的约翰逊法公式用来估测美新杂交褐牛估测体重可行,但本次试验实测和验证牛群数较少,还需大量不断验证以获得更可靠的结果。 相似文献
6.
1活重估测
活重估测的理论依据是体重和体积的关系。因为不同品种、年龄、性别和膘情的牛体型结构差异较大,所以很难用统一的公式来准确估测。一般估测体重要求与实际体重相差不过5%,如相差超过5%则估测公式就不能用。 相似文献
7.
为了分析大通种牛场牦牛体尺与体重的相关性,估测体重的回归分析,对大通牦牛母牛进行称重和体尺测量,根据得出的数据分析其体重与体高、背长、胸围的相关系数,同时估测大通牦牛母牛的体重回归模型。结果表明,大通牦牛母牛体重与体高、背长、胸围之间极显著相关,说明体重与体尺之间存在着明显的线性关系。 相似文献
8.
为了分析2.5岁大通牦牛母牛体尺与体重的相关性,以便在实际工作中应用,在11月份对31头2.5岁大通牦牛母牛进行称重和体尺测量,根据得出的数据分析其体重与体高、体斜长、胸围、管围的相关系数,同时估测大通牦牛2.5岁母牛的体重回归模型。结果显示,大通牦牛2.5岁母牛体重与体高、体斜长、胸围、管围的相关系数分别为0.309、0.713、0.846和0.595,经检验体高、管围与体重的相关系数达到了显著水平(p0.05),体斜长、胸围与体重的相关系数达到了极显著水平(p0.01),得到了3个估测体重的回归模型,估测值与实测值之间相关程度分别为0.923、0.864和0.893。大通牦牛2.5岁母牛体重与体高、体斜长、胸围、管围之间显著相关,说明体重与体尺之间存在着明显的线性关系。 相似文献
9.
4矿物质NRC-2001中,因子分析法用来确定对常量元素和微量元素的需求(维持、泌乳、妊娠、生长)。动物对矿物质的需求总量指能被吸收的矿物质的质量。表3提供了泌乳牛矿物质推荐使用量。5维生素泌乳奶牛对脂溶性维生素需求量如下:维生素A(国际单位/天)=110×体重(千克),维生素D(国际单位/天)=30×体重(千克),维生素E(国际单位/天)=0.08×体重(千克)。6生长后备母牛(90￣590千克)的营养需要青年母牛的营养需求在NRC-2001版本中进行了更新和完善。生长后备牛的目标重量是:第一次交配,占成熟体重55%;第一次产犊,占成熟体重82%;第二次产犊,占… 相似文献
10.
八、青年母牛的饲养管理应注意些什么? 母牛到18月龄已进入体成熟阶段,体内各器官已基本发育完全,生长速度开始减缓。青年母牛是指18月龄至初产(1胎)这一阶段的母牛,为后备母牛(又称发育母牛或生长母牛)的最后一个阶段。此阶段的长短取决于母牛的配妊月龄,若18月龄配妊,此阶段为10个月,每提前一个月配妊,则减少1个月,若15月龄配妊,此阶段为7个月。母牛的初配月龄主要根据母牛的体重,一般认为母牛体重达360公斤以上即可初配。 相似文献
11.
Body measurements of west African dwarf sheep as parameters for estimation of live weight 总被引：2，自引：1，他引：1
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
12.
Growth rates during rearing affect the age and body weight (BW) of replacement heifers at first calving. Diet and disease can affect growth via altered metabolic hormone concentrations, but are difficult to monitor accurately on commercial farms. This study investigated the effect of management and metabolic indices (IGF-I, insulin, glucose and urea) on the growth rate of 509 Holstein-Friesian heifers on 19 UK dairy farms. Size (BW, heart girth, height and crown-rump length) was measured at approximately 1, 6 and 15 months. The mean daily weight gain up to 6 months for all calves was 0.77 kg/day, with extreme variability both between cohorts of calves (range 0.49–1.02 kg/day) and between individual calves within farms (range 0.45–1.13 kg/day). Growth was enhanced by supplemental colostrum, by milk replacer as opposed to whole milk and by ad libitum milk feeding and was reduced by gradual weaning and dehorning after weaning. Larger group size slowed growth before weaning (>6 calves) but increased it post-weaning (>20 calves). These management differences were reflected in altered plasma IGF-I concentrations, which were positively associated with growth throughout the rearing period. Larger calves at 1 month had a greater weight gain up to 6 months. Sub-optimum growth of some heifers within each cohort was established at an early age and resulted in animals reaching the start of breeding at an inadequate size (BW range 209–498 kg at 15 months). This could be alleviated by altered management strategies and improved monitoring of growing heifers. 相似文献
13.
14.
Gundula Hoffmann Annika Bentke Sandra Rose-Meierhöfer Christian Ammon Petra Mazetti Grétar H. Hardarson 《Journal of Equine Veterinary Science》2013
The body weight of horses is an interesting variable for horse owners, as well as for veterinarians. It is useful to have methods of estimation like weight tape or formula, rather than visual estimation, when a weight scale is not available. Different methods of weight estimation exist for adult horses, but to date, there has been no validation of these methods in Icelandic horses. Therefore, three different methods of weight determination (weight scale, weight tape, and weight formula) were compared in this study to investigate whether it is possible to obtain reliable weight measurements of Icelandic horses by using an estimation method. Both the weight pursuant to weight tape and pursuant to weight formula showed no significant differences (P = 1.00 and P = 0.37, respectively) from the actual weight. The correlation between estimated and actual weights was r = 0.94 for weight tape and r = 0.93 for weight formula. However, the differences between the estimated and actual weights were smallest when estimated using an adjusted weight formula: weight (kg) = girth² × length (both in cm)/11,400. In conclusion, the body weight of Icelandic horses can be estimated from the measurements of body girth and length, and weight tape also seems to be a suitable method. 相似文献
15.
[目的]本文旨在寻找陇县改良母牛的生长发育规律,为乳用改良牛核心群的早期选育,固定乳用改良后代的优良性状况提供依据.[方法]随机抽取陇县改良母牛(0.5岁、3岁、5岁以上)个体体尺、体尺指数,采用方差分析和多重比较进行综合分析,通过各年龄组合内不同改良后代之间,横向比较不同年龄组合(0.5岁～3岁～5岁以上),纵向比较其体尺、体尺指数,[结果]显示改良个体0.5岁的体长指数,尻宽指数随着改良代数增加逐渐增大,体躯指数,胸围指数随着改良代数增加逐渐缩小,乳用体型及乳肉体型已基本具备等5条具有规律性.[结论]对0.5岁的早期个体,依照平均体尺、平均体尺指数,坚持"体尺绝对指标高于平均数,体长指数,体躯指数,胸围指数低于平均数,尻宽指数高于平均数"的早期乳用核心群的选育结论,对乳用改良工作具有一定的指导意义. 相似文献
16.
为研究内蒙古二郎山绒山羊体尺、绒毛性状与经济性状间的相关关系,选取1 000只3岁成年母羊进行生产性能测定,并利用SAS 9.0和Excel 2003软件进行统计分析。结果表明,二郎山绒山羊体尺、绒毛性状中体高(X1)、体斜长(X2)、胸围(X3)与体重(Y)之间呈极显著正相关(P<0.01),最优回归方程为Y=-12.0856+0.0821X1+0.4053X2+0.1624X3,回归方程的截距和3个偏回归系数都达到了极显著的程度(P<0.01),说明该方程是最优回归方程。胸围对体重的影响最大,而体高、体斜长和绒细度主要通过胸围对体重产生影响;体高对产绒量的影响最大,其次为绒厚度,但是就体高、体斜长、胸围、绒细度、绒厚度、毛长与产绒量之间并未找到最优回归方程。表明二郎山绒山羊体尺、绒毛性状与经济性状之间存在着复杂的内在联系。 相似文献
17.
WUDUBALA LIU Bin ZHAO Cun-fa LI Yu-rong HE Yun-mei ZHAO Yun-deng TANG Pei-rong TIAN Fu 《中国畜牧兽医》2015,42(5):1245-1252
To study the correlation and regression analysis of body size, cashmere traits and economic traits in Inner Mongolia Erlangshan cashmere goat, we selected the 1 000 3-year-old ewe and carried out production performance measurement, and using SAS 9.0 and Excel 2003 softwares for statistical analysis.The results indicated that a significant positive correlation of body height(X1), body length(X2), heart girth(X3) and weight(Y)in Erlangshan goat.Regression model was Y=-12.0856+0.0821X1+0.4053X2+0.1624X3.The intercept and three partial regression coefficient had reached a very significant extent (P<0.01), and indicating the equation was the optimal regression equation.The heart girth was the biggest influence on body weight, and the body height, body length and cashmere fineness impacted on body weight through the heart girth.The body height was biggest influence on cashmere yield and cashmere thickness for the second.We did not find optimal regression model between body height, body length, heart girth, cashmere fineness, cashmere thickness, hair long and cashmere yield.These results indicated the presence of complex intrinsic link between body size, cashmere traits and economic traits in Erlangshan cashmere goat. 相似文献
18.
秦川牛部分体量性状的遗传参数估测 总被引：5，自引：4，他引：1
本研究选用陕西秦川牛原种场饲养的33头公牛及其603头女儿1978年至2005年的记录资料,采用父系半同胞相关法对秦川牛初生、断奶、周岁及18月龄体重、体高、体长、胸围及体重体高比(BPI)的遗传力进行了统计分析,同时分析了各年龄段体重与体尺的相关性。结果表明,秦川牛初生重、断奶重、周岁重及18月龄体重的遗传力分别为0．4150、0．6136、0．2008和0．6371。同期体重体高比(BPI)的遗传力值为0．6225、0．6464、0．1632和0．4839。各年龄段体重与其它体尺性状均呈较强的正相关。 相似文献
19.
本文旨在研究生长期奶水牛体重与体尺指标的相关关系,为通过体尺指标估测其体重提供科学依据。选取76头健康的11~14月龄生长期奶水牛,用地磅、测仗、卷尺分别进行体重与体尺指标测量。采用Excel中LINEST函数对数据进行多元回归和多项式回归分析,用SPSS 17.0对体重与体尺指标进行相关性分析及主成分分析。结果表明,各体尺指标均在不同程度上影响生长期奶水牛的体重,体重与体高、体斜长、十字部高、胸围、腹围、胸宽、胸深、尻长、尻宽和管围均存在极显著相关关系(P<0.01),其中胸围与体重的相关性最大(P=0.823),其次是腹围、体斜长、胸深、管围等;由体重与各体尺指标间多元回归方程的相关系数r可知,11~14月龄奶水牛体重与体尺间存在较强的线性回归关系,可通过不同的体尺指标预测其体重;从主成分的特征根与累计贡献率来看,由第一主成分关系式可见,体重、胸围、体斜长、腹围、管围等的特征向量较大,对第一主成分的贡献也较大,基本反映11~14月龄奶水牛的体型结构,可称为体型因子,第二主成分为尻宽因子,第三主成分为体高因子。 相似文献
20.
为研究太平鸡早期生长发育规律,提高品种选育效果,采用Logistic、Von Bertalanffy、Gompertz三种非线性生长模型对其体重进行拟合,并对13周龄的体重与体尺进行相关性分析。结果表明：Gompertz模型对太平鸡0～15周龄体重的拟合效果最佳,拟合所得的太平公、母鸡的拐点周龄分别为7.08周、6.84周,拐点体重分别为572.24 g、482.74 g,成熟体重分别为1 555.34 g、1 312.09 g;13周龄太平鸡体重与体尺之间存在不同程度的相关性,公鸡的体重与体斜长、龙骨长、胫长、胫围、骨盆宽呈极显著正相关（P<0.01）;母鸡的体重与龙骨长、胫长、胫围、胸围、骨盆宽呈极显著正相关（P<0.01）。 相似文献