Genetic aspects of body weight and growth parameters as related to reproductive performance in the fowl

1973 ◽  
Author(s):  
John Forrest Tierce
1988 ◽  
Vol 68 (1) ◽  
pp. 69-81 ◽  
Author(s):  
MOHAMED H. FAHMY ◽  
JACQUES J. DUFOUR

Reproductive performance and body weight were studied on 361 ewes, representing Finnsheep (F), DLS (a population of 1/2 Dorset, 1/4 Leicester, 1/4 Suffolk) and seven combinations ranging from 1/8 to 7/8 Finnsheep breeding. Conception rate in yearlings was 61.5% for DLS compared to 89.0% for F with the crosses being intermediate. Conception rate in older ewes was similar in the different genetic groups (avg. 94%). Ovulation rate and litter size at birth of DLS ewes were 1.72 and 1.44 lambs, which was less than half those of F ewes (3.51 and 2.86 lambs, respectively). Both traits increased progressively with an increase in F breeding in crosses and with advances in age. DLS ewes weaned 1.22 lambs compared to 2.03 lambs for F ewes and 1.84 lambs for 4/8 F ewes. The heaviest litters at weaning (31.7 kg) were raised by 4/8 F ewes, followed by 7/8 F (30.8 kg) while those raised by DLS ewes weighed 23.0 kg and F ewes 29.1 kg. Percentage of ova lost per ewe mated averaged 24% and ranged between 18% (DLS and 1/8 F) and 29% (6/8 F). About 3.6% of lambs were born dead and a further 13.8% died before weaning. Preweaning mortality rate was highest in F (22.9%) and lowest in 3/8 F (9.4%). Average kilograms of lambs weaned per ewe exposed was highest in 4/8 F (27.6 kg) followed by F (26.0 kg), whereas that of DLS was the lowest at 18.1 kg. The 4/8 F cross showed 25% heterosis in kg of lambs weaned per ewe exposed and 52.5% increase over DLS. Significant positive linear regressions were calculated for ovulation rate, litter size and preweaning mortality rate on proportion of Finnsheep breeding in crosses. The relation was quadratic for percent ova lost and lamb mortality at weaning. Yearling DLS females weighted 36 kg compared to 44 kg for F yearlings. However, at 5 yr of age DLS ewes weighed 62 kg, 5 kg heavier than F ewes. The heaviest ewes at all ages were the 4/8 F (45 kg at 1 yr, 65 kg at 5 yr). Key words: Reproduction, DLS sheep, Finnsheep, crossbreeding, heterosis, repeatabilities


2021 ◽  
Vol 15 (1) ◽  
pp. 151-155
Author(s):  
Abdul Muumin Sadick ◽  
Iddrisu Mubarik ◽  
Dennis Kodzo Awalime ◽  
Rebecca Akumbilim ◽  
Philip Larweh ◽  
...  

One hundred and twenty (120) 16 weeks old White Leghorn layer breeds were used for the study. The objective of the study was to determine effect of photoperiod on layer chicken. The research was carried out at the Poultry Section of the Animal farm of the Department of Animal Science Education, Akenten Appiah-Menka University of Skills Training and Entrepreneurial Development, Mampong. Four treatments made up of 12 hours of light, 14 hours of light, 16 hours of light and 18 hours of light were used for the study. Each treatment was replicated three times with 10 birds per replicate in a Completely Randomized Design. Birds were exposed equally to common daylight and in the evenings, lights were turned on at specified periods. Growth parameters measured were initial body weight, daily feed intake, daily weight gain and final body weight. Egg traits measured were egg weight, albumen height, yolk color and yolk weight. The data collected were analyzed using General Linear Model procedure of Statistical Analysis System. Results from the study indicated that, varied photoperiod regimes had no significant (P>0.05) effect on initial body weight, daily feed intake but had significant (P<0.05) effect on daily weight gain and final body weight of growth traits. Photoperiod had no significant (P>0.05) effect on the egg characteristics of the white Leghorn layer bird. It was concluded from the study that, increasing photoperiod had no positive effect on growth and egg characteristics of the white Leghorn layer.


PEDIATRICS ◽  
1988 ◽  
Vol 81 (3) ◽  
pp. 379-384 ◽  
Author(s):  
Sharon I. Kurzner ◽  
Meena Garg ◽  
Daisy B. Bautista ◽  
David Bader ◽  
Russell J. Merritt ◽  
...  

The mechanisms underlying growth failure in infants with bronchopulmonary dysplasia are poorly understood. Thirteen infants with bronchopulmonary dysplasia at 6 months of corrected age and 12 full-term healthy control infants matched for age or size were studied. Resting oxygen consumption was measured during natural sleep, and an estimation of the resting metabolic expenditure by indirect calorimetry was performed. Growth parameters were measured, and a nutritional profile including dietary intake, stool analysis, and serum albumin, cholesterol, glucose, and prealbumin was obtained. Seven of the 13 infants with bronchopulmonary dysplasia had growth failure (defined as length and weight less than the tenth percentile of the Babson growth curves). These infants had lower birth weight, lower gestational age, and a greater number of days spent in supplemental oxygen or on mechanical ventilation. There was no statistical difference between the bronchopulmonary dysplasiagrowth failure and bronchopulmonary dysplasia-normal growth infants for dietary intake or stool or serum analyses. However, serum prealbumin showed a significant linear correlation with body weight in infants with bronchopulmonary dysplasia. Resting metabolic expenditure was elevated in infants with bronchopulmonary dysplasia with growth failure and was inversely correlated with body weight in all infants with bronchopulmonary dysplasia. Thus, infants with bronchopulmonary dysplasia and growth failure have increased metabolic demands and decreased prealbumin values suggesting a relative state of protein-calorie malnutrition.


2018 ◽  
Vol 39 (4) ◽  
pp. 1737
Author(s):  
Gustavo Duarte Farias ◽  
Liliane Cerdótes ◽  
Ricardo Zambarda Vaz ◽  
João Restle ◽  
Marcia Ferreira Bitencourt ◽  
...  

This study aimed to evaluate the production, reproductive performance, and productive efficiency of predominantly Charolais cows and their calves (Straightbred, ¾ C, ¼ N) according to body size at calving. Sixty-three cow-calf pairs were used and classified into three weight groups: Light (331.3±5.8 kg), Moderate (385.9±5.3 kg), and Heavy (424.4±6.2 kg). The classes were formed using half standard deviations above or below the average weight of the cows at calving. For each pair, the body weight was evaluated at calving, at weaning (63 days), at the beginning and at end of the reproductive period, and at 9 months for the calves. Pregnancy rates were similar (P > 0.05) between weight groups. The calves did not differ (P > 0.05) in terms of body weight and weight gain from calving until pregnancy diagnosis (210 days). The heavy cows had greater weight variations from 210 days to 270 days than the light cows. The calf production rate (kg calf/cow kept in herds) did not differ between weight groups. However, in relation to the weight of the cows at 210 days, light cows were 11.28% and 13.02% more productive (P < 0.05), than moderate and heavy cows, respectively. Light cows were more efficient than the other classes of cows at calving and at 210 days old. Our simulations showed that there were more kilograms for sale in herds of light cows (53.085 kg) than moderate and heavy cows (52.310 and 52.870 kg, respectively), while maintaining the structures of the herd constant. The size of the Charolais cow did not influence the weight of calves from calving until 7 months of age or their reproductive performance provided they were weaned early. The need for space for the maintenance of the cow-calf pair increased as the weight of the cows increased. In herds with smaller cows, higher numbers and a higher production of weight for sale are observed than in herds with moderate and heavy cows. Light cows were the most efficient at calving and during pregnancy diagnosis at 210 days.


2018 ◽  
Vol 47 (2) ◽  
pp. 76-84
Author(s):  
A Akhter ◽  
SC Das ◽  
MS Hasan ◽  
T Akter ◽  
M Sultana ◽  
...  

The experiment was conducted to compare the growth performance among four genotypes of indigenous chicken namely Non-descriptive Native (ND), genetically Improved Native (IN), Hilly (HC) and Naked Neck (NN) of Bangladesh under free-range rearing system.  A total of 288 day old chicks (DOC) from four genotypes were divided into four treatments having eight replications of each for a period of 12 weeks under free-range system with supplementation of commercial broiler diet. During first 4 weeks, all chicks were kept together, whereas chicks of ND was brooded in the same room but separated by a partition. At 5 weeks of age chicks were randomly distributed to the selected farmers. Growth parameters were recorded to determine the comparative growth performance among four genotypes of chicken. The highest body weight (1110.76 g/bird) was achieved by HC, followed by IN (900.63 g/bird) and NN (831.13 g/bird) at 12 weeks of age. The lowest body weight (734.13 g/bird) however was found in ND chicken. During the growing period under free range rearing (5-12 weeks), HC group consumed the highest amount of feed (2697.02 g/bird) with an average FCR of 3.06 while the lowest feed consumption (2666.13 g/bird) with the highest FCR of 4.90 was observed in ND. IN consumed (2674.63 g/bird) feed with an average FCR of 3.92 and BLRI improved NN consumed (2668.13 g/bird) feed with an average FCR of 4.19. Live weight gains in all the four genotypes of indigenous chicken were changed almost in a similar pattern. Significant differences were observed in live weight, dressing percentage, breast meat, drumstick, thigh meat among the four genotypes of chicken. The HC was superior to other genotypes of indigenous chicken including ND in terms of growth performance, meat yield characteristics and net returns. Bang. J. Anim. Sci. 2018. 47 (2):76-84


Reproduction ◽  
2002 ◽  
pp. 419-427 ◽  
Author(s):  
JG Gong ◽  
WJ Lee ◽  
PC Garnsworthy ◽  
R Webb

Although it has become increasingly clear that fertility in modern dairy cattle is declining in association with increased milk yields, the underlying mechanism is poorly understood. The first ovulation post partum is delayed in dairy cows undergoing selection for genetic merit for milk yield in association with lower circulating insulin concentrations. The aim of this study was to investigate whether feeding a diet to increase circulating insulin concentrations can overcome this delay in the first ovulation post partum. The experiment was a 2 x 2 factorial design (n = 10 per group) involving diet and genetic merit for milk yield. The dietary treatment started on the day of calving and lasted for 50 days. Plasma samples were collected each day and ovarian ultra-sonography was performed three times a week during the experimental feeding period. Milk yield was recorded each day, and body weight and body condition score were determined each week. Milk samples were collected three times a week from day 50 to day 105 post partum, and reproductive performance data were recorded for all the cows as part of the routine farm practice. The dietary treatment induced significant differences in plasma insulin concentrations in both high and low genetic merit cows. Although high genetic merit cows produced more milk, lost more body weight and had lower body condition scores during the experiment, no significant effect of diet was observed on these measurements. The high insulin inducing diet increased the proportion of cows ovulating within 50 days of calving and reduced the intervals from calving to first ovulation, and tended to reduce the intervals from calving to first service and to conception. These fertility parameters were also more favourable in low than in high genetic merit cows, but no interaction between diet and genetic merit was observed for any of these parameters. Genetic merit, but not diet, also affected the number of services required per conception and the conception rate. In conclusion, these results have confirmed that genetic selection for high milk yield is associated with a decrease in reproductive performance in dairy cows. More importantly, this study has demonstrated that it is possible to alleviate this problem by nutritional manipulation.


1985 ◽  
Vol 68 (7) ◽  
pp. 1828-1831 ◽  
Author(s):  
L. Badinga ◽  
R.J. Collier ◽  
C.J. Wilcox ◽  
W.W. Thatcher

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