Several different phenotypes of the native Pramenka sheep have been developed in the Balkan region for different environmental and socio-cultural conditions. Animals from seven West Balkan Pramenka sheep types were analysed for 15 microsatellite markers and for mitochondrial DNA (mtDNA) and the results were used to assess genetic variation within and among the types and to infer the genetic population structure of the Pramenka sheep. Mean expected heterozygosity and allelic richness over the microsatellite loci and sheep types were 0.78 and 7.9, respectively. A Bayesian statistical method for estimating hidden genetic structure suggested that a core of the largest panmictic population was formed by Serbian, Kosovan, Bosnian, Montenegrin and Albanian types, while Croatian and Macedonian types comprised two other main populations, respectively. Mitochondrial DNA analysis revealed two mtDNA haplogroups in the Pramenka sheep, B and A, with a frequency of 93.7% and 6.3%, respectively. A total of 60 mtDNA haplotypes were found in 64 animals sequenced, and the mean nucleotide and haplotypic diversities over the types were 0.013 and 0.945, respectively. Molecular analysis suggests that the West Balkan Pramenka sheep types have their origins in two distinct maternal lineages of domestic sheep and different Pramenka phenotypes tend to form few panmictic populations. The Pramenka sheep represents a valuable resource of genetic diversity in sheep.
SUMMARYSeveral basic -fixed factors on daily milk yield have been examined in total of 132 Awassi breed sheep, during two -year production period (2011 and 2012). The examination includes the following factors: lactation number, lactation type, date of milk recording, number of newborn lambs, month or year of milk recording and length of suckling period. Their influence on individual milk yield measured in morning, afternoon and evening milking, total daily milk yield and percentage of milk fat has been examined. A total of 904 lactation tests in sheep, aged from first to eight lactation were included in the research. All data were analyzed using a multi-factorial fixed model.The influence of certain factors was studied using the F-test. Analyzes were made using the SSPS set of programs. Most of the factors (number of lactation, date of milk recording, month or year of milk recording and length of suckling period), except the number of newborn lambs or fertility, had a highly significant influence (P<0.01) on daily milk production (milk from the morning, afternoon and evening and total amount of milk, as well as % of milk fat) in examined breed of sheep. Highest daily milk production was determined among sheep in sixth lactation and lowest among those in eighth lactation. On the other hand, the highest percentage of milk fat was determined among sheep in seventh lactation and the lowest among those in second lactation.Three types of lactation curve were identified in examined sheep of which most abundant is the one with one peak. These data suggest that the Awassi breed, as breed with high milk production, retains the level of high and standard milk production to an older age, which is a prerequisite for profitable and sustainable livestock production.
Accurate and precise milk recording is one of the most important moments for a successful selection of milking goats. In this context, breeders are constantly making efforts to find the most suitable and cheapest methods for conducting of tests for milk production. The goal of this research was to compare the A4 method (as referent method) with AC method (as alternative method), for determination of milk production, on the day of recording of the indigenous Balkan goat, in the period of 2014-2016 with milking of goats in the morning and evening. It was determined that the difference between the predicted daily milk yield with one milking (in the morning or evening) and the measured milk yield using the A4 method is too low and almost negligible. With the analysis of all factors (year, lactation and number of milk tests), it was determined that the prediction of total daily milk yield, based on the evening milking, provides more accurate result, in relation to the prediction during morning milking, in cases when using the AC method.
Several production traits have been examined in 180 Ovchepolian sheep during a four-year production period (2010-2013). The sheep ranged in age from the first to the 7th lactation and 4319 individual lactation controls were realized in total. Besides the basic statistics, all data were analysed using a multi-factorial fixed model. The influence of certain factors was studied using the F-test and the analyses were made using the SPSS set of programs. Most of the factors (year, lactation, lambing month and number of milk recording) had a highly significant influence (P<0.001) on daily milk production (milk from the morning, evening and the total amount of milk, % of milk fat and kg fat) in this breed of sheep. The month of milk recording also had a significant influence (P<0.05) on all traits. Only fertility had no impact on the variations in the tested parameters, aside from the total daily milk, on which a highly significant influence was manifested (P<0.01). The average milk lactation among the tested sheep population during all four years was, on average, 58 ± 0.247 l, while the production of milked milk for the same period was 37 ± 0.217 l. The length of the lactation period in these sheep for the four years studied averaged 182 ± 0.31 days. The maximal daily milk yield in this sheep population was measured in 2011 (0.302 ± 0.26 l). Regarding their age, the highest daily milk yield was determined in sheep in the third lactation (0.365 ± 0.26), while those in the 7th lactation had the lowest (0.255 ± 0.27).
Comparative study of two, for the marketing most important, egg quality parameters (egg weight and egg shell strength) in two genotypes of commercial laying hens was realized. Egg production, egg weight (size) and egg shell strength in ISA Brown (14,879) and DeKalb White (15,376) layers, housed in battery cages under similar in-house environment and feed complete mixtures according the technological nutrient recommendation, were followed through the laying cycle. Egg weight and egg shell strength were analyzed in the Laboratory for testing egg quality using Egg shell Gauge (Robotmation Co. Ltd., Tokyo, Japan), computerized equipment that perform unbiased, shell breaking strength values. Both genotypes have high egg production that was close to the technological level of laying. No differences in egg number/hen housed were noticed. DeKalb White layers produce on average 1 g bigger eggs than the ISA Brown line layers (64.18 g vs 63.17 g), resulting in better feed to egg mass conversion. ISA Brown layers produce eggs with stronger egg shell (3864.52 g/cm 2 ) compared to DeKalb White genotype (3575.78 g/cm 2 ). High summer temperature influence the strength of the egg shell in both genotypes, resulting in lower strength compared to average egg shell strength values.
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.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.