Considering dairy cattle reproduction, profitability is maximized when every cow gets pregnant at her optimal time after calving (at a low cost). This optimal time of conception has consequences for economically optimal breeding decisions and the value of a pregnancy, both a new pregnancy and a loss of pregnancy (abortion). Some cows are more important to get pregnant than others. This paper di...

Data from a multibreed composite beef cattle population, managed under intensive irrigated grazing conditions, were used to estimate direct additive heritabilities (ha), maternal heritabilities (h 2 m) and maternal permanent environmental effects (c) for birth weight (BW) and weaning weight (WW) of the calf and cow efficiency of the dam (CE: WW/dam weight x 100). Calves born between 1968 and 19...

Fifteen generations of selection were conducted to study responses for litter size at birth (LSB), weight at weaning of standardized litter (LWW), and individual body weight at 8 wk of age (BW8) using golden hamsters as an experimental model for pigs. The experiment involved three lines: selection on an aggregate breeding value of LSB, LWW, and BW8 (line W); selection on an aggregate breeding v...

The impact of polymorphism of the diacylglycerol acyltransferase (DGAT1), butyrophilin (BTN1A1), oxidized low-density lipoprotein receptor (OLR1), and signal transducer and activator of transcription 1 (STAT1) genes on milk production and reproduction traits in 419 Czech Fleckvieh cows was examined using polymerase chain reaction and restriction fragment length polymorphism. The loci DGAT1 and ...

Mink skin size in Finland, as well as in other countries, has increased considerably during last decade. However, there are signs that selection for large body size has a negative impact on litter size (LS) and also for survival of kits. Therefore, it is important to study the genetic relationships among fertility traits and animal size (AS). The variance components for age at first mating (AFM...

Integration of molecular information in breeding value estimation. For many years, breeding value estimation in domestic animal species has been based on the polygenic model. This model relies exclusively on pedigree and phenotypic informations. Molecular markers make it possible to follow the transmission of genes affecting phenotypes and, therefore, has opened new perspectives for evaluation ...

The objective of the present study was to determine polymorphism within the promoter region of somatotropin receptor genes in indigenous Sistani cattle (Bos indicus) and associations between this polymorphism and breeding value of birth weight. The pedigree structure was included by considering 1173 animals with 600 progeny birth weight data obtained from a Zhark breeding station in Sistan and ...

Genetic improvement is based on selecting genetically superior animals. From the phenotypic performance of an animal it is not known whether an animal is genetically superior or whether good performance is caused by favourable management or environmental effects. Genetic principles are applied in genetic evaluation programs like PIGBLUP to determine genetically superior animals which is express...

Genetic improvement of pig performance is a primary tool in enhancing profitability in pig enterprises. The first step of genetically improving livestock is the development of a breeding objective which combines all economically important traits that can be improved by selection. These traits are given economic values that are defined as the increase in profit with a single unit change in each ...

TODOROVA, V., 2007. Fruit characterization and influence of variation factors in pepper kapiya type varieties and breeding lines (Capsicum annuum L.). Bulg. J. Agric. Sci., 13: 309-315 Six varieties and ten breeding lines from Kapiya type were evaluated by some morphological fruit characters at the Maritsa Vegetable Crops Research Institute – Plovdiv during the period 2002 – 2004. The sources o...