Bezdicek J.,Palacky University |
Stadnik L.,Czech University of Life Sciences |
Louda F.,Agriresearch Rapotin Ltd.
Bulgarian Journal of Agricultural Science | Year: 2015
The aim of this study was to evaluate the effect of inbreeding depression on age at first calving in Holstein and Czech Fleckvieh cows. Only cows with a complete pedigree to the fifth generation were used. Data were collected from 34 farms in the Czech Republic. For proper comparison, each inbred cow (n=1046) was assigned to at least one noninbred equal (n=1046). Inbred and noninbred pairs were matched on characteristics such as identical father, first calving interval occurring at the same farm and calves born in the same year and month (± 2 months). The PROC GLM of SAS® with five fixed effects was applied to all data. Inbred Holstein and Czech Fleckvieh cows and their matched noninbred equals were then divided according to inbreeding coefficient into four (event. five) groups. For Holstein inbred groups: FX=1.25; FX=3.125; FX=6.0-12.0; FX=25.0; FX>25; respectively all animals, the following extension of age at first calving was found: +2.7; +6.9; +9.5; +18.5; +26.8; +9.6 days, respectively. While for Czech Fleckvieh inbred groups: FX=1.25; FX=3.125; FX=6.0-12.0; FX=25.0; respectively all animals, the prolongation of age at first calving was detected on the level +2.3; +3.9; +9.8; +21.3; +9.8 days, respectively. This study showed the negative effect of inbreeding on prolongation of age at first calving. Deterioration in this reproduction trait occurred even at low levels of the coefficient FX. At higher levels the differences between inbred and noninbred cows were significant (P<0.05-0.01). © 2015, National Centre for Agrarian Sciences. All rights reserved. Source
Manga I.,Agriresearch Rapotin Ltd. |
Dvorak J.,Mendel University in Brno
Czech Journal of Animal Science | Year: 2010
Alleles A1 and A2 of the Bos taurus CSN2 gene are the most frequent in a number of dairy cattle breeds. In this study, a new allelic discrimination assay using TaqMan fluorogenic probes was developed to detect single nucleotide substitution characterizing the A1/A2 alleles of the CSN2 gene. The method was validated using DNA samples of known genotypes with different concentrations and the results were compared with those for the commonly used problematic ACRS-PCR. We found the TaqMan method to be more effective, 100% reliable and hundred times more sensitive for testing the CSN2 genetic marker in cattle than the ACRS-PCR. As it enabled a rapid analysis of a large number of DNA samples in uniform format without previous DNA quality assessment and without the requirement for post-amplification manipulations, it presents an effective tool for the analysis of large-scale sample sets. The method was applied for testing on a sample of 120 Czech Holstein dairy cows. The observed relative genotype and allele frequencies were as follows: A1A1-0.20, A1A2-0.51, A2A2-0.29; A1-045, A2-0.55. Source
Beran J.,Czech University of Life Sciences |
Stadnik L.,Czech University of Life Sciences |
Bezdicek J.,Agriresearch Rapotin Ltd. |
Louda F.,Czech University of Life Sciences |
And 2 more authors.
Archiv fur Tierzucht | Year: 2012
The objectives were to evaluate the effects of sire and content of fresh or ionised egg yolk in extenders on sperm motility and share of live and dead sperm in collected ejaculate, in thawed artificial insemination (AI) doses, and during thermodynamic testing compared to extenders not containing egg yolk. Ejaculates were collected once a week from 4 Holstein bulls. Each of the 20 ejaculate samples from each bull was diluted with 4 different extenders. AndroMed and Bioxcell (no egg yolk) and Triladyl and Optidyl (fresh, ionised egg yolk) were used. A total of 640 AI doses were analysed. The volume of samples, sperm concentration, and percentage of motile spermatozoa were evaluated after collection, as was sperm motility after thawing of AI doses and during thermodynamic testing. Percentages of live and dead sperm were also evaluated. The data set was analysed using SAS/STAT 9.1 (SAS Institute Inc., Cary, NC, USA). The results confirmed significant (P<0.05-0.01) between-sire differences in the volume, density, and activity of sperm as well as in share of live and dead sperm after collection; in decline of sperm motility in the fresh ejaculate, after thawing, and during the entire thermodynamic test, as well as in the share of live and dead sperm after thawing. The extenders ranked by sperm motility are: Optidyl, Triladyl, AndroMed, and Bioxcell, demonstrating the higher quality of AI doses produced using egg yolk extenders. Differences in sperm motility were significant (P<0.05-0.01) during the entirety of thermodynamic testing. Egg yolk extenders had a significantly (P<0.05-0.01) higher percentages of live sperm after thawing. © Leibniz Institute for Farm Animal Biology. Source
Ghara M.,Indian Institute of Science |
Ghara M.,Indian Agricultural Research Institute |
Ranganathan Y.,Indian Institute of Science |
Ranganathan Y.,Agriresearch Rapotin Ltd. |
And 4 more authors.
Arthropod-Plant Interactions | Year: 2014
Differential occupancy of space can lead to species coexistence. The fig-fig wasp pollination system hosts species-specific pollinating and parasitic wasps that develop within galls in a nursery comprising a closed inflorescence, the syconium. This microcosm affords excellent opportunities for investigating spatial partitioning since it harbours a closed community in which all wasp species are dependent on securing safe sites inside the syconium for their developing offspring while differing in life history, egg deposition strategies and oviposition times relative to nursery development. We determined ontogenetic changes in oviposition sites available to the seven-member fig wasp community of Ficus racemosa comprising pollinators, gallers and parasitoids. We used species distribution models (SDMs) for the first time at a microcosm scale to predict patterns of spatial occurrence of nursery occupants. SDMs gave high true-positive and low false-positive site occupancy rates for most occupants indicating species specificity in oviposition sites. The nursery microcosm itself changed with syconium development and sequential egg-laying by different wasp species. The number of sites occupied by offspring of the different wasp species was negatively related to the risk of syconium abortion by the plant host following oviposition. Since unpollinated syconia are usually aborted, parasitic wasps ovipositing into nurseries at the same time as the pollinator targeted many sites, suggesting response to lower risk of syconium abortion owing to reduced risk of pollination failure compared to those species ovipositing before pollination. Wasp life history and oviposition time relative to nursery development contributed to the co-existence of nursery occupants. © 2014 Springer Science+Business Media Dordrecht. Source
Manga I.,Agriresearch Rapotin Ltd. |
Manga I.,Research Institute for Cattle Breeding Ltd. |
Riha H.,Research Institute for Cattle Breeding Ltd.
Archiv fur Tierzucht | Year: 2011
The present study investigated the K232A mutation of the diacylglycerol O-acyltransferase 1 gene (DGAT1) in 315 Czech Holstein Cows. The allele frequency was found to be 0.19 for the K allele and 0.81 for the A allele. The results of K232A testing were assessed in relation to average daily milk yield (l), percentage of fat, protein, lactose and milk somatic cell count (SCC, thousand/ml). A GLM procedure was used to analyse the differences among genotypes. The K232A genotypes were significantly associated with milk fat percentage (KK, KA>AA [P≤0.05, P≤0.005]) and milk yield (KK, KA>AA [P≤0.05, P≤0.005]). The K allele was also favourable for SCC levels: Cows with the KA genotype had lower SCC levels than those with the AA genotype (P≤0.05), while cows with the KK genotype showed the lowest levels of SCC at all. This new association of K232A suggests the existence of another gene in the centromeric region on BTA14 linked to DGAT1 with direct effect on the SCC. On the basis of a broad range of DGAT1 protein functions and the non-conservative matter of K232A, a direct effect of K232A on the SCC cannot be ruled out either. © Leibniz Institute for Farm Animal Biology, Dummerstorf, Germany. Source