Abstract. A total of 88,745 test-day milk yields (obtained up to 30 days before first insemination) from 55,685 Polish Holstein-Friesian cows were used to estimate the coefficients of simple correlation between milk urea level and selected indicators of fertility, age of cows, milk production level, herd size, season of first insemination, and lactation period. The increase in milk urea level had a significant (P ≤ 0.01) effect on prolonging the calving interval (r = 0.03) and service period (r = 0.01), as well as on increasing the number of inseminations per conception (r = 0.02). The direction and magnitude of the relationships (expressed as the coefficient of correlation) between milk urea level and fertility varied within classes of cow’s age, lactation period, season of first insemination, milk production level, and herd size. The present study showed that it would be beneficial to monitor dairy herds of Polish Holstein-Friesian cows for milk urea level which could contribute to improving their fertility.
Abstract. This study analysed the effect of daily milk yield (28,078 test-day records up to 30 days before first insemination, during the period up to 150 days of the first and second lactation), season of first insemination and reproductive rest period on fertility of 17,618 cows measured as number of services per conception. Data were analysed using the GLM and FREQ procedures of the SAS package. The number of inseminations needed for pregnancy increased with increasing daily milk yield of the cows, especially when the first insemination was performed in summer or when reproductive rest period was shortened to ≤ 60 days after calving.
Abstract. The aim of the study was to compare selected characteristics of the lifetime productivity and longevity of Simmental (SIM) and Montbéliarde (MO) cows, taking into account the reasons for their culling. The analysis included a total of 812 cows (635 SIM and 177 MO) from the Parzniew evaluation region, culled in 2005–2016 after having completed at least one 305-day lactation. The study showed that milk production in Simmental cows began slightly later than in the Montbéliarde breed (886 vs. 878 days). At the same time, they were used longer and lived longer, but were inferior to MO cows in terms of yield of milk and its constituents, per lactation and for their entire productive life. Milk from SIM cows was also found to have higher content of fat and dry matter. Analysis of the reasons for culling showed that Simmental cows were most often culled due to sterility and reproductive disease (35%), while in Montbéliarde cows the main causes were poor yield and udder disease (30.5%) and random causes and other causes (30.5%). In both breeds, the least common cause of culling was old age (6.2% in SIM and 2.8% in MO).
Abstract. Bees are natural pollinators, which are able to pollinate most flowers in the world. The serious problem of bee population is an external parasite mite Varroa destructor that causes many viral and bacterial diseases of bees like American foulbrood, European foulbrood or black queen cell virus. It is very important to find a safe and effective treatment against Varroa destructor. There are several methods to fight the parasite, one often used is to remove capped drone brood. Another method is to use various chemical compounds. The aim of this study was to evaluate the effectiveness of five commonly applied commercial products: flumethrin, coumaphos, amitraz, formic acid and thymol. According to the obtained results, the effectiveness of these compounds was about 90%, 82%, 91%, 57% and 56%, respectively. Fumigation with amitraz turned out to be the quickest and the most effective method to fight against Varroa. All treatment were carried out in private apiaries located in north-eastern Poland, in Podlaskie Voivodeship. Every chemical compound was tested on six bee colonies.
Abstract. The Polish Konik Horse (PKH) is the only conservation breed of horses that descends directly from tarpans. Since 1949 the Research Station in Popielno houses one of the largest breeding PKH centers. Retrospective studies were carried out on a group of Polish Konik breeding mares from stable farming in the number of 14 to 22 mares, depending on the season (311 observations in total), aged 3–20 years and weighing 380–430 kg. The basic criteria for assessing breeding activities of stud farms were analysed, including conception, pregnancy and foaling rate. Over the period from 2000 to 2016, the conception rate was 94.21%; pregnancy rate was 93.24% and foaling rate at parturition was 86.17%. The 70.73% of mares became pregnant after the first course of mating, whereas 18.64% became pregnant after the second course of mating. The cases of early embryo resorption or twin pregnancies were sporadic (0.96% and 1.29%, respectively). The high conception, pregnancy and foaling rate is the evidence of a high reproductive potential of PKHs.