Relationships between physiological indicators in blood, and their yield, as well as chemical composition of milk obtained from organic dairy cows.

Background: The occurrence of metabolic overload in cows maintained in organic herds is very likely, because organic production promotes feeding with high roughage diets and discourages supplementation with concentrates supplementation. It has the potential to negatively affect milk quality. The aim of this study was to determine the influence of physiological indicators in blood, reflecting the energy metabolism and liver status of dairy cows kept in organic herds, on the content of bioactive components in milk and the influence of lactation stage and feeding season on changes in milk components.

Differences in whey protein content between cow's milk collected in late pasture and early indoor feeding season from conventional and organic farms in Poland.

Background: The aim of the study was to investigate bioactive whey protein concentrations in cow's milk collected in late pasture (LP) and early indoor feeding (EIF) season from conventional and organic farms in Poland.

Results: Results showed that in the LP somatic cell count (SCC) was higher under organic farming conditions. However, percentages of protein and fat were higher under conventional farming conditions.

Relationships between sexual behaviour, dominant follicle area, uterus ultrasonic image and pregnancy rate in mares of two breeds differing in reproductive efficiency.

Weak or equivocal expression of oestrous behaviour, related to different level of mares' reactivity, may cause problems in oestrus detection and thus influence the reproductive efficiency. The aim of the study was to test whether a breed characterised by low pregnancy rate and high emotional reactivity (Thoroughbreds) differs in oestrous behaviour from a primitive breed with higher reproductive efficiency (Koniks). Additionally, the follicle size was examined to determine how it influences the intensity of oestrus and uterine ultrasonic image and whether the pregnancy rate differs in relation to the intensity of oestrous behaviour and the size of the dominant follicle(s) area on day preceding ovulation in both breeds.