No abstract

temperature distribution on the surface of an animal’s body. The surface temperature values obtained in IRT depend on the quantitative impact of the conditions of the surrounding environment and the thermoregulatory response of the animal. Besides the blood perfusion volume, the skin temperature depends on the metabolic rate of tissues, the type and colour of the hair coat, and the thickness of the adipose tissue. In a healthy organism, the temperature distribution between individual parts of the body shows a high degree of symmetry. Analysis of the surface temperature distribution of a given area of the body of an animal which is in homeostasis with the external environment provides a great deal of valuable information. By comparing the same parts of the body, we can easily identify hot spots, and the additional knowledge gained during more extensive veterinary diagnostics increases the chance of establishing the cause of this condition. The reliability of IRT depends on the technical parameters of the cameras, environmental conditions, the operator’s experience, the animal’s individual characteristics, and the testing methodology. As many factors can affect the surface temperature distribution of an animal’s body, and thus the result of the thermographic measurement, the effect of any stimuli interfering with the measurements should be minimized during thermal imaging. Additionally, in order to reduce the risk of misinterpretation of the image, normalization protocols for imaging parameters, i.e. standards ensuring reliable results, should be applied. The main limitation in the implementation of these standards in thermography of livestock animals is that it is not possible to compare thermograms made under different environmental conditions. Research has been carried out to assess the suitability of thermal imaging cameras in diagnosing inflammatory changes in the skin of cattle. The technique was found to have great potential in predicting local inflammation (hoof, udder or skin disease). Normalization protocols must be developed for imaging parameters, i.e. standards that will ensure reliable results in a variety of environmental conditions.

The material for the analyses comprised blood samples collected from 65 Zlotnicka Spotted (Zlp) sows and 43 Zlotnicka White (Zlb) sows born and kept in two herds in Wielkopolska. While analysing reproductive, fattening and slaughter traits, information was collected on 290 litters, including 180 litters of Zlp sows and 110 litters of Zlb sows. Intravital measurements were taken using a Piglog 105 for the evaluation of the mean backfat thickness, lean meat content and loin eye thickness. The aim of the research was to determine the effect of selected genotypes on reproductive, fattening and carcass performance traits of the two indigenous pig breeds (Zlotnicka White and Zlotnicka Spotted), kept and bred in Poland. The frequency of RYR1 genotypes indicates that the number of animals with the RYRTT genotype carrying a mutation in the RYR1 gene was low in the Zlotnicka breeds. In the herd of Zlb sows, a statistically significant negative effect of the RYRCT genotype on piglet wastage up to 21 days of age was found. The highest wastage rate was recorded in the group of heterozygotes. The frequency of the genotypes indicates that the DD genotype typical of animals with polymorphism in the GH/MspI gene occurred rarely in the analysed population of the Zlotnicka breeds. A statistically significant effect of the GH/MspI genotype on litter weight at 21 days of age was observed in the population of the Zlb sows. The heaviest piglets were born to sows with the DD genotype, while the lightest piglets were born to sows with the CC genotype. The frequency of the LEP genotypes indicates that the number of animals with the TT genotype was very low in the population of the Zlb pigs. No animal with the TT genotype was found in the Zlp herd.

For over 2.5 million dairy cows subject to assessment in Poland in 2005-2010, gestation length was analyzed. This trait follows a normal distribution, and it was found that the acceptable upper limit of gestation length for the Montbéliard and Simental breeds was 306 days, this being significantly different from other breeds. For the remaining dairy cattle breeds the value was 298 days. For cows with gestation length exceeding these limiting values, parentage control would be advisable.

Analyses were conducted on pedigrees of 845 animals registered at the Hovawart Club in Poland (113 dogs and their ancestors). The degree of inbreeding was calculated for the whole population (0.0026) and separately for male dogs (0.0021) and bitches (0.0031), and the coefficient of mean relationship was calculated for the entire population (0.0064), among male dogs (0.0064), among females (0.0073) and between males and females (0.0061). The inbreeding and relationship coefficients obtained are lower than those estimated for Polish populations of other dog breeds. The calculated effective number of founders (268) and ancestors (233) may indicate rather low genetic diversity. Preferences of breeders concerning coat colour were discussed. Black and tan coat dogs dominated at first, followed by blond ones, and over the last five of the analysed years black coat dogs emerged.

An automatic milking system allows cows to present their full production capability by not limiting them to a specific time when the milking occurs or a fix number of milkings per day. The beginning of the first lactation is a key point in terms of subsequent milk production. The aim of the present study was to indicate the relationship between the milking frequency of primiparous cows during the first month of lactation and their subsequent milk performance. Material of the study consisted of 25 Polish herds of Holstein–Friesian dairy cattle. All cows were milked with the use of an automatic milking system. Animals were divided into five groups, depending on the milking frequency in the first month after calving (MFF). The collected data were statistically processed using the multifactorial ANOVA. The best milk and milking parameters characterised primiparous cows, for which the average number of milkings per day was at the level of 3–3.5 or above, this group did not have a preferred time for their milking. This group of cows milked more frequently during the first month of lactation (MFF5) and had the highest milk yield (MY) and milking duration. The highest culling percentage (57.77%) was noted within the group of primiparous cows with the lowest milking frequency during the first month of lactation (MFF1). MFF5 animals maintained better milk and milking parameters in all months of lactation than did those in the other groups. Older animals, that calved after the 28th month of life, and those that calved during warmer seasons, showed the tendency to have a lower milking frequency and poorer milk and milking parameters. The findings obtained in the present study are interesting in terms of their potential use, because they show that frequent milking during the first month after calving corresponds to a better overall MY during that lactation. Hopefully, by promoting frequent milkings at the beginning of lactation, farmer may increase the overall lactation MY.

The study attempted to estimate the lactation curves of primiparous dairy cows in relation to their feeding management. Therefore, the first aim of the study was to determine and compare the lactation curves of primiparous dairy cows using Wood’s model and to estimate the association between the lactation curves and feeding management. The second objective was to investigate the effect of the culling rate on improvement in the milk yield of primiparous dairy herds. The study was conducted on four commercial dairy farms of Polish Holstein–Friesian cows using different feeding systems (TMR—total mixed ration and PMR—partial mixed ration) and management (T1—one TMR throughout lactation; P1—one PMR throughout lactation; T2 and T3—three feed periods such as FRESH, TMR I and TMR II according to days in milk). The data used for the study were obtained from monthly milk performance evaluations of 1662 primiparous cows conducted by the Polish Federation of Cattle Breeding and Dairy Farmers throughout the year 2015. Wood’s lactation model was used to plot curves for milk yield, fat and protein content, lactose content, and milk urea contents. The highest milk yield for the whole lactation and in the peak lactation phase was recorded for cows in herd T1. This herd reached peak lactation on day 105 of milking, with an average milk yield of 42.1 kg, which was about 5 kg more milk than in the other herds. The study showed that the culling of primiparous cows in herd T1 after 30, 60 and 90 days of lactation prevented a significant reduction in milk yield in a 305-day lactation. It also increased average milk production by 1586.9 kg per primiparous dairy cow.

Nienartowicz-Zdrojewska A., Sobek Z., Różańska-Zawieja J. (2018) Research material included data on gestation length of 15 436 cows of Polish native breeds. These were: White Backed (BG; 324 records), Polish Red (RP; 5396 records), Polish Black and White (ZB; 3508 records), and Polish Red and White (ZR; 6208 records). The calvings took place in 2005-2009, and we analysed two calving seasons, lactation number, the degree of calving difficulty, sex, and body weight of newborn calves. The effect of birth year on gestation length and birth weight of offspring was statistically significant, whereas calving season had statistically highly significant effect on both. Gestation length in the analysed breeds was 281. 02, 283.35, 280.5, 281.53 for BG, RP, ZB, and ZR, respectively. The birth body weight heritability was 0.13 (RP), 0.33 (ZB) and 0.40 (ZR).