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.
One aim of the research was to challenge a previously selected repeatability model with 2 other repeatability models. The main aim, however, was to evaluate random regression models based on the repeatability model with lowest mean-squared error of prediction, using Legendre polynomials up to third order for both animal additive genetic and permanent environmental effects. The random regression and repeatability models were compared for model fit (using likelihood-ratio testing, Akaike information criterion, and the Bayesian information criterion) and the models' mean-squared errors of prediction, and by cross-validation. Cross-validation was carried out by correlating excluded observations in one data set with the animals' breeding values as predicted from the pedigree only in the remaining data, and vice versa (splitting proportion: 0.492). The data was from primiparous goats in 2 closely tied buck circles (17 flocks) in Norway, with 11,438 records for daily milk yield and 5,686 to 5,896 records for content traits (fat, protein, and lactose percentages). A simple pattern was revealed; for daily milk yield with about 5 records per animal in first lactation, a second-order random regression model should be chosen, whereas for content traits that had only about 3 observations per goat, a first-order polynomial was preferred. The likelihood-ratio test, Akaike information criterion, and mean-squared error of prediction favored more complex models, although the results from the latter and the Bayesian information criterion were in the direction of those obtained with cross-validation. As the correlation from cross-validation was largest with random regression, genetic merit was predicted more accurate with random regression models than with the repeatability model.
Abstract. The aim of this investigation is to determine changes in concentrations of biochemical and haematological parameters, as well as metabolic hormones in the blood of Tsigai ewes in the first third of lactation. The study included 10 ewes Tsigai breed monitored during three periods of lactation: 20 days, 40 and 60 days of lactation. Ewes were fed feed mixture (300 g/day) and meadow hay ad libitum. A significant decrease of concentrations of Ca and Na was recorded in the blood of sheep at the 40th day of lactation and later an increase at the 60th day of lactation. The opposite trend was determined for concentrations of P-inorganic. Also it was determined a significant decrease in Fe content and an increase in the concentrations of glucose, triglycerides and total protein in the first third of lactation. In the blood of ewes at 40th day of lactation it was found a significant decrease of the activity of AST and LDH in contrast to ewes at 20th day of lactation. Concentrations of T3 and T4 hormones were slightly increasing in the first third of lactation, but the differences were not significant. The blood insulin concentrations were significant increased in the first third of lactation. Haematological blood parameters in lactating ewes did not differ significantly and was within the reference values. Determining the concentration of biochemical and haematological parameters and concentrations of blood thyroid hormones and insulin in the first third of lactation are imposed as a precaution in order to better monitoring of Tsigai ewes during lactation.
Buša is an old endangered autochthonous breed of the western Balkan, especially Bosnia-Herzegovina, Kosovo and Albania. A related breed is Gatačko, derived from Buša × Tirolean Grey crossbreds. Fifteen purebred Buša cattle and thirteen Gatačko animals were genotyped for polymorphisms at the kappa-casein gene by a Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) essay. The alleles A, B and C were found and the allelic frequencies were 0.46 (A), 0.46 (B) and 0.08 (C) in Buša cattle and 0.58 (A) and 0.42 (B) in Gatačko. Only AA, AB, BB and BC genotypes occurred. Further alleles were not detected and are therefore either absent in both populations or rare. The allele »B« found in this small population will be useful for a sire selection program in the future.
Investigations have been conducted on Slavonia during a three year period on six locations, two per each year during June (in the first year = Vinkovci and Beli Manastir; in the second year = Valpovo and Djakovo; in the third year Slatina and Donji Miholjac). Six samples from the soil, pasture and sheep wool, as well as 15 sheep blood samples were taken from each locality. There was a deficit of selenium content in the soil on four locations in the second and third year (0.18; 0.14; 0.10 and 0.07 mg/kg) and an adequate content on locations Vinkovci and Beli Manastir in the first year (0.98 and 0.71 mg/kg). The locality Valpovo was characterized by the highest selenium concentration in pasture, blood and wool of sheep, as well as by the lowest blood enzymes activities (ALT, AST, CK, LDH) when compared to other locations. Selenium concentration in pasture was under the critical range on all locations (from 0.006 to 0.03 mg/kg DM), except the locality Valpovo in the second year (0.05 mg/kg DM). Serum selenium concentrations (from 0.035 to 0.082 mg/L) on all locations were below the adequate range for adult sheep and differed among locations. Activities of enzymes in the blood of sheep (AST: 3.59, CK: 4.93 and LDH: 6.87 μkat/L) showed severe selenium deficiency. Selenium concentrations in the wool were under the critical level on all locations (from <0.0002 to 0.06 mg/kg). The results regarding selenium in wool showed that, apart from blood selenium and activities of plasma enzymes (AST, CK, LDH), wool should also be taken in account as a selenium status indicator
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