25 research outputs found
Genetic parameters for quail body weights using a random regression model
A model including fixed and random linear regressions is described for analyzing body weights at different ages. In this study, (co)variance components, heritabilities for quail weekly weights and genetic correlations among these weights were estimated using a random regression model by DFREML under DXMRR option. Data of 1046 pedigreed quail were used. Individual live weights were obtained weekly from hatching to six weeks of age. Records for the same bird were taken as repeated measurements and single measurement error variance was assumed to be constant for all ages. Orthogonal polynomial regressions (on the Legendre scale) of sixth order were sufficient to model the additive genetic, phenotypic and permanent environmental (co)variances. Heritability estimates for ages were moderate, ranging from 0.007-0.61 and estimated measurement error variance was 9.60 g2. Correlations were found positive among weights. Genetic correlations were higher than phenotypic and permanent environmental correlations. The correlations between adjacent periods are more closely correlated than between remote periods.
South African Journal of Animal Science Vol.34(2) 2004: 104-10
Genetic parameters for quail body weights using a random regression model
WOS: 000224120900006A model including fixed and random linear regressions is described for analyzing body weights at different ages. In this study, (co)variance components, heritabilities for quail weekly weights and genetic correlations among these weights were estimated using a random regression model by DFREML under DXMRR option. Data of 1046 pedigreed quail were used. Individual live weights were obtained weekly from hatching to six weeks of age. Records for the same bird were taken as repeated measurements and single measurement error variance (alpha(e)(2)) was assumed to be constant for all ages. Orthogonal polynomial regressions (on the Legendre scale) of sixth order were sufficient to model the additive genetic (alpha(a)(2)), phenotypic (alpha(p)(2)) and permanent environmental (alpha(pe)(2)) (co)variances. Heritability estimates for ages were moderate, ranging from 0.007-0.61 and estimated measurement error variance was 9.60 g(2). Correlations were found positive among weights. Genetic correlations were higher than phenotypic and permanent environmental correlations. The correlations between adjacent periods are more closely cot-related than between remote periods
Effects of meal-time feeding and protein restriction on walking ability and some bone and carcass properties in broilers
This experiment was designed to investigate the effects of meal-time feeding and protein restriction on performance, gait score (GS) and carcass and bone traits in broilers. A total of 420 1-day-old chicks were wing banded and randomly distributed into 21 pens with 20 chicks each. At 7 days of age, chicks were weighed and randomly assigned to one of the three treatments: (1) control (C) feed (23.02% crude protein (CP)) was available ad libitum; (2) meal-time feeding (MF); control feed was available from 0100 to 0900 h and from 1500 to 2300 h. Food was withdrawn from 0900 to 1500 h and whole wheat (10 g/bird per day) was dispersed on the floor from 7 to 21 days; and (3) low-protein (LP) diet (19.71% CP) was fed to the chicks from 7 to 21 days. All of the groups were fed ad libitum from I to 7 days of age and from 21 to 45 days of age with a standard commercial diet Individual body weight was measured on days 7, 21 and 45. Feed consumption was measured from 7 to 21 days and from 21 to 45 days. Forty-two chicks were humanly slaughtered and eviscerated for bone evaluation, on days 21 and 45. Also carcass characteristics were determined on day 45. Control group body weight was significantly higher (P < 0.05) at 21 and 45 days of age than the MF and LP groups which did not differ Feed intake was reduced by meal-time feeding and LP diet (P < 0.01). Feed efficiency was the best in the MF group during the period of 21 to 45 days of age (P < 0, 0 1). In the control group, shank was significantly longer than that of the LP group and tibia breaking strength was higher than that of the MF group at 21 days (P < 0.05). However shank width, tibia wet weight and tibia mid-diaphysis ash percentage of the MF group were significantly lower than those of the C and LP groups at 21 days of age (P < 0.05). GS, shank and carcass and tibia bone traits on day 45 were not significant among groups. No compensatory growth and walking ability improvement were observed at 45 days of age for broilers fed with MF and LP between 7 and 21 days of age
Effects of dietary ascorbic acid on performance, carcass composition and bone characteristics of turkeys during high summer temperature
WOS: 000253878600019Heat stress is major welfare problem in the poultry industry. Huge economic losses occur every year because of mortality and decreased production due to high environmental temperatures. This experiment was conducted to determine the effects of level of inclusion of ascorbic acid supplementation to the diet on performance, carcass composition and bone characteristics of male turkeys during high summer temperature. A total of 120 day-old turkey chicks were wing banded at hatch and randomly distributed into 3 treatment groups. Three diets were formulated to provide a similar nutrient profile with the exception of using three graded levels of ascorbic acid, namely 0, 150 and 300 mg/kg of the diet. The experimental diets were used from 0 to 18 weeks of age. Body weights, feed intake and feed conversion ratio, slaughter weight, carcass yield, portions, composition and thigh and breast pigmentation of the turkeys were not affected by ascorbic acid (p>0.05). Also, shank and tibia bone characteristics were not affected by ascorbic (p>0.05)
The colostrum quality and composition of simmental and brown swiss heifers [A qualidade e a composição do colostro de novilhas simental e de pardo suiço]
The present study was conducted to determine the quality and composition of colostrum samples obtained from Simmental and Brown Swiss heifers on a Turkish dairy farm in Ödemiş, İzmir. The average volume of colostrum obtained from Simmental and Brown Swiss heifers at the first milking was 3.4 L and 3.8 L, respectively. Average colostrometer (Ig) and Brix values were determined as 105.1 mg/mL and 104.9 mg/mL, 29.97 % and 29.68 % of the samples (P>0.05). No significant differences were observed between colostrums’ chemical compositions—including total solids, total protein, solids-not-fat, somatic cell counts (SCC), total bacterial counts (TBC), and energy values of the breeds - except for lactose concentration (P<0.05). The means of TBC were 781,000 and 634,000 CFU/mL for Simmental and Brown Swiss, respectively. The correlations between colostrometer and Brix values in Simmentals and Browns Swiss were 0.85 and 0.81, respectively (P<0.01). On the other hand, the correlations between Log10SCC and Log10TBC in both breeds were found to be 0.66 and 0.65 (P<0.05), respectively. According to the results of the present study, the fat, protein, lactose, and total solid concentrations of both Simmental and Brown Swiss (dual-purpose breeds) were higher than the values reported for Holstein dairy breeds. Although colostrum quality of both breeds was found to be good in terms of Ig concentration, their total bacterial counts were high. Bacterial counts can be reduced with adequate hygiene practices and good colostrum management. © 2018, Universidade Federal de Uberlandia. All rights reserved.2011-ÖMYO-001The authors would like to thank Ege University Scientific Research Department for the funding of this project (2011-ÖMYO-001), EBILTEM for the coordination of projects of Vocational Collages and Savaş and Barış BURGAZLIOĞLU brothers for their approval of the project to be implemented in their facilities. -
The effects of several cow and herd level factors on lameness in Holstein cows reared in Izmir province of Turkey
This study was carried out to determine the prevalence of lameness and risk factors for lameness. Data of 1078 Holstein cows from 34 farms in Izmir province of Turkey were evaluated. Lameness was determined by using a Lameness Score (LS) scale with 5 levels. Mean prevalence of lameness (LS = 3) was 28.3%. The percent of the cows with LS 1-4 or 5 were found to be 37.9, 33.8, 20.9%, 5.8 and 1.6%, respectively. Cow-level variables were parity, days in milk, body condition score and hygiene score of lower rear legs. There were 18 herd level variables used to explain the variation in the prevalence of lameness among the herds. LS data were analysed using individual and multifactorial binary logistic regression. About 12 of the 22 potential risk factors investigated in the study were found to be significant (p<0.10) in the individual logistic regression analysis. However, only 9 of the 12 factors remained in the final multifactorial logistic regression model. These significant 9 factors on lameness were parity, body condition score, herd size, animal keeper, total area per cow, soil area per cow, frequency of scraping, ratio of concentrate feed to total feed intake and consulting a feeding expert. © Medwell Journals, 2010