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1.
为探究雏鸡不同初生重对后期体重和均匀度的影响,以及不同初生重雏鸡的生长发育规律,运用线性回归分析及Gompertz非线性模型对123只某褐壳纯系蛋种鸡体重进行0~12周龄生长曲线拟合和分析.结果表明:初生重与12周龄体重极显著相关,并对12周龄体重有极显著影响;Gompertz生长曲线模型显示,不同初生重组体重拐点均在...  相似文献   

2.
蛋鸡育雏期生长发育直接影响产蛋成绩,衡量雏鸡发育的主要指标是体重,五周龄体重和以后的产蛋成绩呈显著的正相关。实践证明雏鸡五周龄体重和以后产蛋率、平均蛋重、开产日龄和死亡率的相关系数分别为0.73、0.56、-0.49、-0.310,五周龄雏鸡体重低于标准时,即使以后采取措施使实际体重达到标准体重,也会相当程度地影响到今后产蛋生产性能。  相似文献   

3.
法系獭兔数量性状遗传参数估计   总被引:4,自引:2,他引:2  
用单元内同胞相关法对法系獭兔3个世代的繁殖性状和生长发育性状进行了遗传力估计,并对6月龄的体重体尺进行了相关分析。结果表明:产仔数(0.15)和初生窝重(0.20)属中等遗传力性状;21日龄个体重(0.42)、32日龄断奶个体重(0.38)及成活数(0.42)皆属高遗传性状;3月龄体重(0.37)及体尺(0.28-0.37)属较高遗传力性状,而6月龄的相应性状遗传力值(0.47-0.63)明显地高于3月龄。3月龄体重与6月龄体重、6月龄体尺间皆有很高的遗传相关(0.81-0.96)和表型相关(0.46-0.79)。  相似文献   

4.
试验旨在探究蛋种鸡育成前期体重对其产蛋性能的影响,为该品系蛋种鸡的体重管理及选育分析提供科学数据和管理思路。本试验将10周龄京红1号蛋种鸡按体重分为4组,并记录和分析产蛋鸡的开产日龄及不同周龄下的体重、产蛋数以及蛋重指标。结果表明:10周龄不同体重对蛋种鸡的开产日龄、产蛋期体重、产蛋数、蛋重均产生一定的影响。体重越大开产日龄越小,A组开产日龄最大(P<0.05),D组最小(P<0.05),B组与C组的开产日龄处于A组与D组之间,且二者之间差异不显著;除56周龄各组间体重差异不显著外,28周龄和36周龄各组体重随10周龄体重增大而增大(P<0.05);产蛋后期(48周龄和56周龄),B组和C组的产蛋数显著高于A组和D组;A组的36周龄蛋重显著小于B、C、D组,而B组和C组间差异不显著。本试验结果提示,10周龄体重处于平均体重的90%~110%范围内,京红1号蛋种鸡后期的综合产蛋性能更佳。  相似文献   

5.
番鸭的蛋重对受精率孵化率及鸭苗初生重的影响   总被引:7,自引:0,他引:7  
对黑白羽番鸭蛋重对受精率、孵化率及鸭苗初生重的影响程度进行观测分析。结果表明,大蛋(86-90克)和小蛋(70-74克)受精率都低,分别为85.38%、86.96%;受精蛋孵化率亦低,分别为67.57%、68.75%;出壳弱雏多,健雏率分别为90.71%、91.81%。中等蛋(75-85克)受精率高达93.97%,受精蛋孵化率亦达87.45%,健雏率为98%-99%。种蛋重与雏鸭初生重成正相关,初生重为蛋重的68.68%。  相似文献   

6.
蛋鸡5周龄体重对其产蛋期的各生产性能指标具有密切相关。即是说,如果某一蛋鸡群的5周龄全重能达到其体重标准或更高一些,则预示该鸡群在产蛋期将早开产,产蛋多及死亡率低。而生产实践中在多数情况下使蛋鸡的早生长发育(体重)达到要求并不容易。本文针对海赛克斯蛋鸡在国内的实际生产情况,对影响蛋鸣早期生长发育的因素及其相应的饲养管理技术要点给予分析与介绍。一.孵化方面的因素1.种蛋的大小对初生雏的体重的明显的影响,并由此影响蛋鸡早期的体重增长,一般讲一日龄雏鸡的体重约为入孵种蛋的三分之二。种蛋蛋重越大则雏鸡的初…  相似文献   

7.
(一)根据雏鸡生理特点巧应对1.雏鸡生长迅速,代谢旺盛,对饲料和环境的要求高。蛋用雏鸡2周龄体重约为初生时的2倍,8周龄为15倍。所以既要保证雏鸡的营养需要,又要保证良好的空气质量。雏鸡羽毛生长快、更换勤,因此,雏鸡日粮的蛋白质,尤其是含硫氨基酸水平要高。  相似文献   

8.
白番鸭数量性状间相关性分析   总被引:5,自引:2,他引:3  
对RF系白番鸭蛋重与受精率,孵化率及初生重;见蛋白龄、性成熟期和产蛋率;耗料量和产蛋率;产蛋率与周龄等数量性状间相关性进行观测分析。结果表明:蛋重大(86~90g)受精率高(97.7%),但孵化率低(67.4%);中等蛋重(76~85g)孵经率高(81.0%);蛋重与初生重呈强直线正相关(r=0.9408)。经观测各组RF系白番鸭从见蛋到产蛋率无显著差异(P〉0.05);产蛋期间母鸭群的耗料量与产  相似文献   

9.
试验旨在研究不同蛋重对雏鸡初生重和器官发育的影响。选取90枚种鸡蛋按蛋重分为5组,每组18枚:Ⅰ组(59~62 g)、Ⅱ组(62~65 g)、Ⅲ组(65~68 g)、Ⅳ组(68~71 g)、Ⅴ组(71~74 g)进行为期21 d的孵化。出雏后对雏鸡进行称重、采血和屠宰,记录并分析数据。结果表明:(1)雏鸡初生重与蛋重呈显著正相关;(2)雏鸡的心脏、肝脏、脾脏、肺脏、肾脏、小肠、肌胃重量与蛋重呈正相关,Ⅴ组的腺胃指数显著低于Ⅰ组(P<0.05),其余器官指数各组间无显著差异(P>0.05);(3)Ⅴ组雏鸡血清中三酰甘油的含量显著高于Ⅰ、Ⅱ组(P<0.05),Ⅴ组高密度脂蛋白含量显著低于Ⅰ、Ⅱ组(P<0.05),Ⅴ组胆固醇的含量显著高于Ⅰ、Ⅱ、Ⅲ组(P<0.05)。综上,蛋重与雏鸡的健康水平相关,且蛋重较大不利于雏鸡的健康。  相似文献   

10.
矮小型肉鸡的早期选择研究   总被引:1,自引:0,他引:1  
研究测定了部分携带有dw基因鸡群从出壳到10周龄体重及跖长的生长发育情况,并对前后期体重、跖长作相关分析。结果证明:dw基因对雏鸡2周龄前的体重增长及跖长发育无显著影响,4周龄时矮小型鸡与正常型鸡相比体重轻38.38%,跖长短13.28%,差异显著。初生重、跖长与10周龄体重及跖长无显著性相关;4,6,8周龄各周体重与10周龄体重间均表现为极显著相关;本研究得出的6条直线回归方程可用来根据早期体重预测10周龄体重。矮小型鸡和正常型鸡一样可根据4周龄体重进行早期选种。4,6,8周龄各周跖长与10周龄跖长间均有极显著相关;对矮小型鸡跖长的选择可提前到4周龄进行,而不必等到10周龄之后,以利于种鸡早期进行限制饲养。  相似文献   

11.
Weight tapes and body weight estimation formulas are routinely used to determine the body weight of a horse when a scale is not available. The established formula to estimate body weight in mature horses is weight (kg) = (heartgirth2 × body length)/(11,880 cm3). Two variations of the body length measurement have been used, measuring distance from the point of the shoulder to the ischial tuberosity (Point) or to the midpoint of the distance between the widest part of the stifle and the tail when viewed from the rear (Stifle). The objective of this study was to evaluate the accuracy of a commercial weight tape and the body weight estimation formula using both body length measurements in estimating weight of adult horses. Horses (n = 145) were weighed on a portable livestock scale, and measured for height at the withers, heart girth circumference, and body length by using the Point and Stifle measurements. A commercial weight tape was used to estimate body weight on 110 horses. The two formula weight estimations and the weight tape estimation were significantly different from the actual weight and from each other. The mean difference between actual weight and tape weight (n = 110) was 65.81 kg, whereas the differences between actual weight and the formula estimations (n = 145) were 17.25 kg for the Point measurement and 45.26 kg for the Stifle measurement. The estimation formula using body length measurement with the ischial tuberosity endpoint most closely estimates the actual body weight of the horses.  相似文献   

12.
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   

13.
The purpose of the study was to test the therapeutic effects of novel vaccines for reducing weight gain and increasing weight loss in diet induced obesity (DIO) model. Male C57BL/6 J mice, fed a 60% Kcal fat diet for 8 weeks prior to the start of the study, were vaccinated via the intraperitoneal route with two formulations (JH17 & JH18) of chimeric-somatostatin vaccines at 1 and 22 days of the study. Control mice were injected with PBS. All mice continued to be feed the 60% Kcal fat diet for the 6 week study. Body weights were measured two times a week and food intake was measured weekly. At week 6, mice were euthanized and a terminal bleed was made and antibody levels to somatostatin and levels of insulin-like growth factor 1 (IGF-1) were determined. Vaccination with both vaccine formulations induced a statistically significant body weight change over the study period, as compared with PBS controls. Percentage of baseline body weight was also significantly affected by vaccination during the study period. Vaccinates finished the study at 104% and 107% of baseline weight, JH17 & JH18 respectively, while untreated controls reached 115% of baseline weight. Food intake per mouse was similar in all mouse groups during the entire study. Control mice did not demonstrate any antibody titers to somatostatin, while all vaccinated mice had measurable antibody responses (> 1:500,000 titer). IGF-1 levels were not statistically significant among the groups, but were elevated in the JH18 vaccinates (mean 440.4 ng/mL) when compared with PBS controls (mean 365.6 ng/mL). Vaccination with either JH17 or JH18 chimeric-somatostatin vaccines produced a statistically significant weight loss as compared with PBS controls (P < 0.0001), even though the DIO mice with continually fed a 60% Kcal fat diet. The weight loss/lower weight gain observations were even more significant, as all mice consumed similar amounts of food for the entire study. The presence of high levels of anti-somatostatin antibodies at 6 weeks was correlative with the weight observations and confirmed the success of vaccination.  相似文献   

14.
The purpose of the study was to test the therapeutic effects of novel vaccines for reducing weight gain and increasing weight loss in diet induced obesity (DIO) model. Male C57BL/6 J mice, fed a 60% Kcal fat diet for 8 weeks prior to the start of the study, were vaccinated via the intraperitoneal route with two formulations (JH17 & JH18) of chimeric-somatostatin vaccines at 1 and 22 days of the study. Control mice were injected with PBS. All mice continued to be feed the 60% Kcal fat diet for the 6 week study. Body weights were measured two times a week and food intake was measured weekly. At week 6, mice were euthanized and a terminal bleed was made and antibody levels to somatostatin and levels of insulin-like growth factor 1 (IGF-1) were determined. Vaccination with both vaccine formulations induced a statistically significant body weight change over the study period, as compared with PBS controls. Percentage of baseline body weight was also significantly affected by vaccination during the study period. Vaccinates finished the study at 104% and 107% of baseline weight, JH17 & JH18 respectively, while untreated controls reached 115% of baseline weight. Food intake per mouse was similar in all mouse groups during the entire study. Control mice did not demonstrate any antibody titers to somatostatin, while all vaccinated mice had measurable antibody responses (> 1:500,000 titer). IGF-1 levels were not statistically significant among the groups, but were elevated in the JH18 vaccinates (mean 440.4 ng/mL) when compared with PBS controls (mean 365.6 ng/mL). Vaccination with either JH17 or JH18 chimeric –somatostatin vaccines produced a statistically significant weight loss as compared with PBS controls (P < 0.0001), even though the DIO mice with continually fed a 60% Kcal fat diet. The weight loss/lower weight gain observations were even more significant, as all mice consumed similar amounts of food for the entire study. The presence of high levels of anti-somatostatin antibodies at 6 weeks was correlative with the weight observations and confirmed the success of vaccination.  相似文献   

15.

Mature weight for Large White sows was estimated as the asymptote of a negative exponential growth curve. The data consisted of 2620 weight recordings from 147 sows for the period 1995?1999. Body weight was recorded every 2 weeks from 150 days of age until first service and at parturition and weaning in each parity. A starting point of 150 days was chosen in order to fit the Brody function to the data. Estimates of mature weight in relation to the number of records available (5?10, 11?15, 16?20 and >20) per sow were 285, 258, 260 and 270 kg, respectively. The goodness of fit was calculated as a residual standard deviation (9.7?15.4). No significant effect on mature weight was found for feeding level during rearing or age at first service. The estimated mature weights increased with the number of records available and was more reasonable if the weights were collected throughout the growth and reproductive period.  相似文献   

16.

Sheep feeding regimes were studied in years when little roughage was available by comparing two levels of concentrate (high and low) and three types of roughage [silage, hay and ammonia-treated (AT) straw]. The duration of the experiment was two production years (1995 and 1996) and included 121 ewes. The traits recorded were live weight for ewes, ewe performance (number of lambs, birth weight, average daily weight gain) and slaughter data (class, value and weight). After 14 weeks, ewes fed low-concentrate AT straw were 6-12 kg lighter ( P < 0.01) than the other ewes, and tended to be undernourished. Lambs from these ewes were up to 1.5 kg lighter at birth ( P <0.01) than the other lambs. No difference was found at the end of the experiment. The gross margin in the group fed the high-concentrate AT straw diet was 205 NOK higher ( P <0.01) than the group with the lowest gross margin (low-concentrate hay). Wool and wood eating was found in groups fed large amounts of concentrate and silage.  相似文献   

17.
文章通过分析托佩克大白头胎母猪初配日龄、体重、背膘和分娩前体重、背膘以及妊娠期间背膘和体重的变化与首胎繁殖成绩的关系发现,托佩克大白猪繁殖最佳条件为:配种日龄为239~245日龄,配种体重为150~160 kg,妊娠期间体重增加88~95 kg,分娩前体重为240~250 kg,配种背膘为14~20 mm,妊娠期间背膘...  相似文献   

18.
The objective was to determine factors influencing social organization in postpartum Angus cows and its effect on variation of cow–calf weight after 90 d. Postpartum Angus cows (N=90) with no history of puerperal problems, a calf suckling, and body condition score (BCS) no less than 3 were allocated into 3 groups of 30 (A, B, and C) according to parity (P) and cow body frame (CF). Using the agonistic interactions recorded during the study, a raw dominance value with subsequent Arc-sin conversion (Arc-sin DV) was calculated to generate a linear social dominance order (DO) with 3 social categories (dominant—D-, intermediate—I-, and subordinate—S-cows). The effects of postpartum body weight (PPBW), BCS, CF, and P on Arc-sin DV were statistically analyzed using ANOVA. Similar procedure was applied to analyze the effects of group, P, CF, and DO on cow body weight at 90 d (CW90), and the effects of DO of dams, P, group, calf gender (CG), and sire within breed (SWB) on calf body weight at 90 d (CFW90). Cows with larger CF and heavier PPBW obtained greatest (P<0.0005) Arc-sin DV. The youngest and the oldest cows tended (P<0.10) to obtain the lowest Arc-sin DV. After 90 d of trial, D cows were heavier than I (P<0.002) and S cows (P<0.0001). Calf birth weight was influenced by SWB (P<0.03) and P (P<0.05), and D cows had heavier (P<0.05) calf at birth than S cows. At 90 d, calf body weight was influenced by P (P<0.03) and DO of dam (P<0.008). Thus, calf weight at 90 d increased with DO of dams. In conclusion, CF, PPBW, and to a less extent P, influenced DO. Parity and CF influenced PPBW. Variation of CW90 was influenced by DO. Calf birth weight was influenced by SWB, P, DO of cow, and CG. Meanwhile, CFW90 was influenced by P and DO of cow. Interactions among social organization, management strategies, calf growth, and reproductive aspects need more attention.  相似文献   

19.
A 9-year-old multiparous Thoroughbred broodmare presented for evaluation of acute signs of colic. The patient had a 4-month history of poor appetite, weight loss, and decreased body condition after parturition, despite appropriate feeding by the farm to minimize weight loss associated with increased nutrient requirements. The patient was diagnosed with a diaphragmatic hernia through transabdominal and thoracic ultrasonography. The diaphragmatic hernia was repaired surgically under general anesthesia.  相似文献   

20.
莫嘉凌  韦波 《广西蚕业》2000,37(1):53-55
通过对我所保育的蓖麻品种全茧量、茧层量这两个主要经济性状进行分析,结果表明,我所保育的21个蓖麻蚕品种仍然保持基因型和表现型的多样性,仍是一个有效的品种资源。各品种对环境的抗性有差异。  相似文献   

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