Evaluation of the hoof's temperature variations depending on lesion presence, measurement points and leg position.

In order to determine the possibility of using infrared thermography (IRT) in preventing lameness in dairy cows, the aim of this study was to evaluate temperature variations depending on the lesion presence, measurement points and leg position. The study used about 3 000 IRT records from 60 Holstein cows housed in a free-stall barn. Surface temperature measurements were taken at two regions of the hooves: the region of the coronary band, and the region of the skin up to 2 cm above the coronary band. A highly significant (P = 0.004; 0.006, P < 0.01) difference in temperature was observed between healthy and diseased legs at both measurement points. Additionally, a significant (P = 0.029; 0.037; 0.045; 0.012; 0.018, P < 0.05) or highly significant (P = 0.004; 0.006, P < 0.01) difference in temperature values between the front and rear legs was established for both measurement points, i.e., the coronary band and the skin. Despite confirming the potential applicability of infrared thermography in the detection of lameness, it is crucial to consider the significant influences of the environmental factors, impurities, and animal-related factors.

Differences in response to heat stress due to production level and breed of dairy cows.

The climatic conditions in Croatia are deteriorating which significantly increases the frequency of heat stress. This creates a need for an adequate dairy farming strategy. The impact of heat stress can be reduced in many ways, but the best long-term solution includes the genetic evaluation and selection for heat stress resistance. In order to create the basis for genetic evaluation, this research determined the variation in daily milk yield (DMY) and somatic cell count (SCC) as well as the differences in resistance to heat stress due to production level (high, low) and breed (Holstein, Simmental) of dairy cattle breed in Croatia. For statistical analysis, 1,070,554 test-day records from 70,135 Holsteins reared on 5679 farms and 1,300,683 test-day records from 86,013 Simmentals reared on 8827 farms in Croatia provided by the Croatian Agricultural Agency were used. The results of this research indicate that the high-producing cows are much more susceptible to heat stress than low-producing especially Holsteins. Also, the results of this research indicate that Simmental breed, in terms of daily milk production and somatic cell count, could be more resistant to heat stress than Holstein. The following research should determine whether Simmentals are genetically more appropriate for the challenges that are in store for the future milk production in this region. Furthermore, could an adequate production level be achieved with Simmentals by maintaining the heat resistance?

Changes in the Fatty Acid Composition of Milk of Lipizzaner Mares during the Lactation Period.

The composition and properties of the milk fat of mares' milk is interesting from a nutritional standpoint. The aim of this study was to determine the nutritional value of Lipizzaner mare's milk for possible human consumption and identity the influence of the parity and stage of lactation on its fatty acid (FA) composition. This study was conducted on 17 Lipizzaner mares from a state stud farm in the Slavonian region (eastern Croatia). Mares were hand-milked twice during lactation in the fourth and sixth months. Significantly higher contents of MUFAs (monounsaturated fatty acids) and PUFAs (polyunsaturated fatty acids) and lower ratios of n-6/n-3 were found in the fourth month of lactation. This parity significantly affected the PUFA/SFA ratio (polyunsaturated fatty acids/saturated fatty acids), with lower values found in older mares. The fatty acid composition of mare's milk that is especially high in UFAs (unsaturated fatty acids) is considered to be beneficial for consumers.