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Heredity of polledness in cattle
HEGROVÁ, Kateřina
Most cattle breeds were originally naturally horned. The horns were used as a tool of defense and a manifestation of dominance in the herd. With increasing pressure to increase the efficiency of breeding and increase the safety of both animals and care-givers, horned cattle are being dehorned. However, this does not correspond with welfare requirements. In 2009, the complete genome of cattle was sequenced, which started a series of researches in the field of heredity. Genetic manifestations of horns or polledness are controlled by the autosomal locus polled, located on chromosome pair BTA1, characterized by two alleles, for the dominant P allele representing polledness, and for the recessive allele p for horns. In cattle we encounter 4 mutations of these alleles Celtic, Frisian, Mongolian and Guarany. Manifestations of polledness are also influenced by alleles for the presence of scurrs Sc and sc, or alleles for the manifestation of the so-called African horns Af and An. Thanks to the testing of individuals using microsatellite markers or the SNP method, it is possible to mark genetically polled individuals and thus help breeders to expand hornless breeds.
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Feeding and related social behaviour during limited browse in a herd of captive elands (Taurotragus oryx) - expariment with tree like branch holder.
LIŠKOVÁ, Markéta
The thesis is focused on the analysis of feeding, comfort and social behavior in a herd of farmed eland (Taurotragus oryx) initiated by the presentation of browse to the tree stand. In 2008 and 2010 were obtained 15-hour video behavior gradually with three different adult males of elands at Czech University of Life Sciences farm at Lány. The aim of this work was to evaluate the accessibility of a limited food source (browse), the frequency of feeding behavior in relation to a rank in the herd, age and sex and find out if the stand can be also used as a enrichment to increase proportion of comfort behavior (scratching, grooming). Adult male in the herd has always been high ranking and no one attacked him, followed by females and juveniles. Access to a limited browse was influenced by the level of aggression of adult female towards the younger and lower ranking ones, these females attacked with the same frequency also the youngs. The dominant male attacked especially the dominant females. The length and frequency of all types of behavior were related to a sex of the individual, the rank and the presence of a calf. With higher rank individuals had longer access to a browse, display longer comfort behavior than lower ranking ones. We can conclude that both types of behavior performed more often males than females. Length and frequency of interactions with browse was supported during absence of calf in vicinity of stand.
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