Reproductive efficiency in terms of fertility, Prolificacy and survival rate are considered the major components of overall efficiency in sheep productivity. While fertility of Awassi ewes is moderate to high depending on feeding and management practices, however, litter size is low and Awassi is not considered a prolific breed. Heritability estimates of these traits are rather low, and reflect small genetic variation in these traits. The possible avenues for increasing reproductive capacity environmentally and genetically are discussed in the text of this review article.
A total of 439, 436 and 437 records of average daily milk yield (ADMY), milk yield after weaning (MYAW) and total milk yield (TMY) respectively were analyzed. Data used in this study obtained from mountain does at private project in Raselain Village/ Akre Region/ Duhok governorate. The data related to two milking seasons (2016-2017) and (2017-2018). The animals were allowed to graze natural pasture and stubble, straw and ground oak acorns were providing whenever required. Does were flushed 2 weeks prior to mating and kidding season. The flock was placed on a regular health program. Does were milked by hand at biweekly intervals starting from the first week post kidding till the does are dried off. ADMY was calculated by multiplying test day milk yield * 2. While TMY calculated by multiplying ADMY by lactation period. Statistical analysis of data was carried out by using GLM procedure within SAS programme. This model includes effects of doe's age, year and season of kidding, birth's type and sex and weight of doe at kidding on milk traits. Effect of doe added to above model as a random effect to estimate their repeatability using Restricted Maximum Likelihood method. Overall means for ADMY, MYAW and TMY were 0.727, 54.49 and 129.32 kg respectively. Results showed that the age of does had significantly higher effect (P< 0.01) on all studied traits of milk. Does aged 4.5 years produce significantly higher ADMY (0.772 kg), and accordingly TMY (136.88kg), while higher MYAW recorded for does aged 3.5 years beside 4.5 years. The effectiveness of year was significant (P< 0.01) on all milk yield traits. Also season of kidding affect all studied milk traits significantly (P< 0.01), whereas the does kidding in winter had significantly higher ADMY, MYAW and TMY than those kidding in spring season. The effects of type of birth and sex of kids were significant on all milk traits. Does with female twins produced significantly more ADMY comparing with does having male or female singles only. Does with female twins and male and female twins produced significantly much MYAW. Does with female twins yield significantly higher TMY when compared to those in the other groups, on the same time there were no significant differences in TMY of does with male twin and does with male and female twin. There was no significant effect of doe weight at kidding on all studied traits and the regression coefficients were positive for ADMY (0.0003 kg/kg), and TMY (0.085 kg/kg) while the regression was negative for MYAW (- 0.0024 kg/kg). Repeatability estimates of ADMY, MYAW and TMY were 0.24, 0.31 and 0.27 respectively. It sum: due to the effectiveness of the fixed factors on the studied traits, hence adjusting records is necessary. The estimates of repeatability indicate that selection of does as well their kids depending on their milk production will improve the productivity in the next year.
This study aimed to survey the data collected from several commercial broiler farms in Akre region in order to evaluate the live body weight, carcass traits and their cuts, also to compare commercial projects of poultry in different farms in order to determine the best farm for rearing poultry. Statistical analysis was accomplished using the programme of Statistical Analysis System (SAS), also pairwise correlations among studied traits were determined.At 42 days of age, broilers' live body weight, and dressing percentage averaged 2276.50 g, and 76.52 percent, respectively, and the differences between the 4 farms used in this study were significant in all the mentioned traits. The differences in breast, thigh, back, neck and wing percentages were significant due to the farm and their averages were 36.75%, 25.21%, 18.78%, 5.82% and 8.19% respectively. The lymphoid organs including spleen % and bursa % were averaged 0.155% and 0.179% respectively, and the differences in all the lymphoid traits according to farm were significant. The higher coefficient of correlation (0.78) obtained between breast % and back % and was very highly significant, while the negative and higher value (-0.83) calculated between live body weight and back % and also was very highly significant. It can be concluded that a significant difference was found in all studied traits which may be due to differences in some factors including rearing system. Some of the correlations between each pair of studied traits were positive and highly significant, so to improve some traits, the breeder can focus on measuring other related traits.
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