Czech Journal of Animal Science - In Press
Genetic Parameters for Foot and Claw Disorders in Czech Holstein cattleOriginal Paper
Ludmila Zavadilová, Eva Kašná, Zuzana Krupová, Miloslava Štípková, Michaela Brzáková
Our study investigated the genetic variability of specific foot and claw disorders, namely dermatitis digitalis, sole ulcer, and three broader categories (infectious diseases, claw horn lesions, and general claw disorder), in Czech Holstein cows. We also examined their genetic relationships with clinical mastitis and key fertility traits. Using both linear and threshold animal models, we determined that heritability estimates for foot and claw disorders were consistently higher when employing the threshold model. A significant finding was the genetic correlation between sole ulcer and dermatitis digitalis, which ranged from 0.21 (calving to 305 days in milk) to 0.53 (calving to 90 days in milk). Furthermore, we observed stronger genetic correlations between clinical mastitis and overall foot and claw disorders, claw horn lesions, and infectious diseases during early lactation (calving to 90 days in milk) compared to the entire lactation period. Within this early lactation phase, the strongest genetic correlation was identified between clinical mastitis and claw horn lesions. Interestingly, our research uncovered a unique genetic link between days open and dermatitis digitalis, suggesting that a genetic predisposition for a higher occurrence of dermatitis digitalis may coincide with shorter days open. These results underscore the importance of implementing distinct genetic selection strategies for infectious claw diseases and claw horn lesions in dairy cows. This distinction is crucial due to their differing genetic correlations with other economically important traits, ultimately contributing to a better understanding of claw health genetics and its application in breeding programs.
Population structure, genetic diversity, and reproductive efficiency in the autochthonous Busha cattle breedOriginal Paper
Aneta Piplica, Mato Čačić, Anamaria Ekert Kabalin, Maja Maurić Maljković, Ivan Vlahek, Velimir Sušić, Sven Menčik (email: sven.menčik@vef.unizg.hr)
Autochthonous cattle breeds represent important resources of genetic diversity. The Busha cattle breed is reared in the Balkan Peninsula and is characterised by high adaptability, resilience, longevity, small body size, and low maintenance and production requirements. During the 36-year observation period, the total population of the autochthonous Busha cattle breed in the Republic of Croatia amounted to 10,411 animals. Pedigree completeness for the overall population, considering the first parental generation, was 97.1%. The average inbreeding coefficient was 2.44%, ranging from zero to 42.6%, while the average relatedness coefficient was 3.56% in the total population. The effective population size, calculated in the reference population based on the individual increase in inbreeding, was 63.3. The probabilities of gene origin in the reference population were fe – 38.0, fa – 33.0, and fg – 25.4, indicating a loss of genetic variability due to genetic drift (fg/fe – 0.66) and a bottleneck (fe/fa – 1.15). In the population of the autochthonous Busha cattle breed, the effective number of ancestors (fa) was smaller than the effective number of founders (fe). Increased relatedness among animals was observed, which could affect the long-term conservation of the population.
The impact of domestication process on eggshells microstructure in Gallus gallus, Anser anser and Anas platyrhynchosOriginal Paper
Joanna Rosenberger, Łukasz Pawelec, Regina Grugel
The domestication process has had a substantial and varied impact on animals in terms of anatomy, physiology, and behaviour. Poultry species that are particularly important for humans, with the most significant being chickens, geese, and ducks. However, it is not well understood whether, or to what extent selection influences eggshell structure compared to wild ancestors. In the presented study, we compared eggshells from three species: Red junglefowl and its four domesticated forms: Green-legged partridge, Lohmann Brown, Ko-Shamo, meat type breeder (Cobb500), Greylag goose, and two domesticated breeds: Bilgoraj goose and White Koluda Goose, as well as Mallard duck and domesticated crossbreed KhO-01. The analyses revealed significant differences in the eggshell structure both between species (p < 0.001) and among breeds (p < 0.001 for chicken and geese, and p = 0.039 for ducks). Domesticated forms tend to had fewer mammilary knobs per mm2 (p = 0.004), which were larger (p < 0.001) and smaller coverage of the mammilary knobs (p < 0.001). Analyses showed significant correlations between body mass and egg size with eggshell characteristics (p < 0.001). Considering that domesticated forms are usually larger, it cannot be conclusively determined whether changes in structure result from the domestication process itself or are physiologically linked to body mass and egg size. The relatively high similarity between the eggs of the wild ancestor and the Ko-Shamo breed – which exhibits substantial morphological changes but has a body mass similar to that of the Red junglefowl supports this interpretation..