In the present study, we examined the suitability of seven asymptotic nonlinear models to describe body weight growth of Hemsin male and female sheep from birth to 36 months of age and, using the selected functions, to provide a biological interpretation for this growth. The weight-age data for this study were obtained from records of 108 Hemsin female and male sheep held in variety breeder flocks of Artvin province in Turkey. The sheep records were collected between 2008 and 2010 with measurements taken at birth, 2nd, 3rd, 6th, 12th, 18th, 24th, and 36th months of age. Body weight-age data from Hemsin sheep were used to obtain a growth pattern for sheep, with the use of Negative exponential, Brody, Gompertz, Logistic, Bertalanffy, Richards, and Janoschek nonlinear functions. Comparisons between these functions were based on coefficients of determination and residual squared error. The R 2 values of the models ranged from 0.971 to 0.989 for males and from 0.951 to 0.991 for males. In both sexes, the Brody, Richards, and Janoschek models, with equal R 2 as 0.99, were superior to the others. However, the Brody was precise on its parameters and easy to interpret than Richards and Janoschek functions.
Abstract. Many researchers who have studied the relationships between milk protein
polymorphisms and some yield traits in dairy cattle have reported
incompatible results. In this study, in order to examine the overall
relationships between milk protein genes known as major genes
(CSN1S1, CSN2, CSN3, and BLG) and some yield traits (daily
milk yield, lactation milk yield, fat yield, fat content, protein yield, and
protein content), a meta-analysis was performed using some genetic models
reported in the results of previous studies on cattle. The results suggest
that the relationships of major milk protein genes with other factors should
be studied using the codominant genetic model in general. Relationships
among some CSN3 genotypes and fat yield, fat content, and protein
content, and relationships between some BLG genotypes and daily milk
yield, fat content, protein yield, and protein content were significant
(P<0.05). No significant (P>0.05) relationships were
found between these genotypes and other milk production traits. In addition,
no significant (P>0.05) relationships between the
CSN1S1 and CSN2 genotypes with the milk production traits
examined were observed.
The effects of three finishing systems on carcass composition and other characteristics of meat were studied in 15 young Eastern Anatolian Red bulls in Eastern Turkey. For 93 days, five bulls grazed pasture (P), five grazed the same pasture and were given concentrate supplementation (P + C), and five grazed the same pasture for 93 days, and then for an additional 40 days, they received concentrate in a barn (PF). Carcasses of the P bulls were lighter and leaner than those of the PF animals. Compared with the P carcasses, PF carcasses had a greater percentage of kidney, pelvic, and heart fat (P < 0.05), marbling score (P < 0.05), fat thickness over the longissimus dorsi (LD) muscle (P < 0.05), and percentage of ether extractable lipids (P < 0.05). The LD of P carcasses was darker (P < 0.01) in color and the meat was tougher. The ratio of polyunsaturated to saturated fatty acids in LD intramuscular fat was higher (P < 0.05) for P bulls than for P + C and PF. P carcasses contained a lower (P < 0.05) proportion of saturated fatty acids than PF carcasses. It is concluded that pasture-based finishing results in a more favorable fatty acid profile of meat and produces a healthier food, but the meat is darker and tougher.
This research aimed to improve Hemşin sheep grown by local people in Artvin province between 2006 and 2010. Growth characteristics such as live weight and daily live weight gains of Hemşin lambs in the various periods were examined for this purpose. The effects of some environmental factors such as herd type, sex, birth type, age of dam, color and year on these factors were also examined. In the study, growth characteristics of lambs born from 6000 ewes and 300 dams were measured based on performance tests and a selection practice was performed. Elite, multiplyres elite and base herds were established. The heritabilities belonging to the properties in question were determined. The breeding value for daily live weight gains up to the end of grazing season in the fifth year was calculated. At the end of five years span of the research, to improve the growth characteristics of Hemşin sheep and to increase live weight gain to be obtained from each lamb were targeted. Except the daily live weight gain in the grazing period, all the other growth characteristics increased at the examined period. Heritabilities of the characteristics in the study is found as 0.213±0.114, 0.385±0.119, 0.411±0.144, 0.402±0.136, 0.418±0.143 ve 0.420±0.066, respectively. As a result, in terms of examined growth characteristics of Hemşin sheep measured by individual performance testing, it is determined that Hemşin sheep can be breed by local people to improve its growth traits.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.