Slaughter yield, carcass tissue composition and meat quality of 8- and 9-week-old ducks from A44 pedigree strain were investigated. Duck males and females, aged 8 and 9 week were distinguished by a great slaughter yield (68.0 and 67.6%) and also good breast muscles content (17.3 and 18.5%). Whereas an increase in skin with subcutaneous fat content and abdominal fat weight was slight (by 0.9% and 4.1 g). Values pH of breast and leg muscles ranged from 5.60 to 6.30 in 8 week alike in 9 week of rearing. Values pH point that in meat of males and females there was not quality disadvantages of PSE and DFD type. Duck breast muscles characterized greater protein content than leg muscles. Proportion of protein in breast and leg muscles grew larger, and fat proportion decreased together with the age of ducks. It was found that 8-week-old males distinguished by less fat content in breast muscles than females.

Ducks and drakes for slaughter raised up to the 7th week of age, from two ancestral paternal strains A44 and A55 were evaluated and compared. Birds of both sex from A44 strain weighed 2884 g on average, in the 7th week of rearing, whereas those from A55 strain weighed 2887 g. The feed intake per one duck to 7th week of age from both strains was 9.51 and 9.50 kg accordingly. Economic efficiency indices of the 7-week-old birds of both strains were high and exceeded 500 points. A44 strain birds were characterized by bigger slaughter yield (67.7) in comparison to A55 ducks. Proportion of breast muscles of both strains was similar, however proportion of leg muscles (13.6%) was significantly higher in A55 birds. Drakes of both strains had a bigger weight of abdominal fat and giblets than ducks. The quality of meat, measured with breast and leg muscles pH, was better in A55 ducks in contrast with A44.

The aim of the studies was to compare Na, K, Ca, Png and Mg concentrations on the mandibular osseous tissue of 109 roe deer bucks (Capreolus capreolus L., 1758) of an „ecological field population” coming from the northern, central and southern region of Western Pomerania. Higher concentration of ash in 1g dry metter (0.36 g ± 0.04) was recorded in the mandibular osseous tissue of bucks from central region of Western Pomerania. The higher concentration of calcium (62.8 mmol·l^–1 ± 7.8), the lower concentration of magnesium (18.2 mmol·l^–1 ± 1.9) and the higher ratio Ca:Mg (3.49 ± 0.58) was recorded in bucks bone tissue from northern region. These results showed that influence of osseous tissue of bukcs mandibles in investigated macroelements depends from region of Western Pomerania.

The effect of reducing the energy level of a diet to 80% maintenance requirement over the latter 64 and 50 fattening days of Black-and-White and Holstein-Fresian young bull crossbreds on their fattening capacity was investigated. The change of ration caused a   decrease of daily gains in this specific period, however no significant decrease of daily gains of the whole fattening time was found. Moreover, no significant effects of changed ration on utilization of proteins and energy per 1 kg body weight gain were noted. Young bull crossbreds fattened to higher body weight took more nutrients than those fattened to lower of body weight.

The experiment aimed to determine the effect of the oestrus induction by Serodin and Dinolityc preparations in gilts. The research were conducted on the farm of industrial pigs fattening on 188 crossbreed gilts (Polish Large White x Polish Landrace) with body weight of 100-110 kg and aged 5.5-6 months. The animals were divided onto 3 groups: one control and two experimental. The preparations mentioned above were the factors differentiating experimental groups and were given to gilts in form of injection once in group II (Serodin) and twice in group III (Dinolityc+Serodin). After gilts introduction to the basic herd the estimation of their reproductive use and rearing to the second farrowing was conducted. Obtained results proved that the oestrus induction in gilts in a big farm simplifies the technological groups formation in the stage of mating and pregnancy and causes that more sows with the oestrus induced stay in a basic herd to the third reproductive cycle. However, the highest value of economic fertility was stated for sows without the induction of oestrus.

This study determined the contents of chemical elements in muscule tissue, liver and kidney of 20 white improved breed kids. The animals were fattend to 90 and 150 days of age. Meat and selected internal organs, i.e. liver and kidneys, were as the experimental material. Samples of tissues were tested for the content of Fe, Ca, Mn, Cu, Pb,Cd and Zn using atomic absorption spectroscopy (AAS). The mean concentration of the Zn-52.583 mgּkg^-1 and Fe-22.233 mgּkg^-1 in tested muscle tissue of group II. The contents of Cu, Mn, Fe, Pb, Ca were included within the physiological limits and did not make any toxic threat.

The experimental material comprised three groups of calf-bulls derived from crossbred dams, having 50% Black-and-White and 50% Red Angus genotype, and sires of the three beef breeds: Limousin, Red Angus, and Salers. After slaughter, the carcasses were evaluated for lean and fat content according to the EUROP carcass grading system. Hot carcasses were weighted and measured. The right halves were dissected for retail cuts. The carcasses were mostly assigned to the leanness grade U and fat grade 2. The bulls of all the studied genotype groups were of similar slaughter performance and the differences found were small and, in most cases, non-significant.

The studies were carried out on 480 Peking ducks from the paternal A44, A55 and maternal P66, P77 strains. The birds were housed indoors on a slatted floor. Concentrate mixtures for ducks were provided ad libitum. Ducks from the investigated strains characterized by a great body weight. In the 9th week of ducks’ life males weighed beyond 3 kg, and females 2.85 kg. Up to the 9th week, feed intake per one duck and per 1 kg of body weight ranged from 11.9 to 13.6 kg, and from 3.8 to 4.1 kg, respectively. Slaughter yield was from 66.2 to 70.1% but females characterized by a greater slaughter than males. Proportion of breast and leg muscles in ducks’ carcasses increased together with the age of birds and was from 24.8 to 28.0% in the 9th week of life. Skin with subcutaneous fat content was stated from 21.3 to 28.9% of carcass, and it was mostly greater in females within each strain.

The Diamond V XPO preparation is obtained in fermentation process of corn grains with use of Saccharomyces cerevisiae yeast. The experimental material constituted 60 dairy cows of Black-and-White breed upgraded with 70-90% of HF. The animals were kept on straw in the stanchion barn. The cows were by analogue method divided into two experimental groups, and feed during whole year with the same diets. Cows from experimental group additionally received Diamond V XP preparation, given individually to the animal at dose 60 gּdayּhead^-1 in dry period and 100 gּdayּhead^-1 during lactation. Once per month during 305 days of lactation milk yield and composition were controlled. For cows received in daily ration addition Diamond V XP daily milk yield during 3 month of lactation were by 3.7 kg higher. The milk yield for 305 days of lactation was 9976 kg and was by 686 kg higher than in control group. There was no influence of Diamond application on milk composition. During 2 months of lactation the level of minerals in milk and blood serum were higher.

The investigation was performed on 1085 Black-and-White cows with a large contribution of the genes of HF breed. The aim of this study was to determine the genetic differentiation degree on the basis of leptin gene polymorphism (LEP/HphI and LEP/Sau3AI). The genotypes analysis was performed using PCR-RFLP method. Frequencies of LEP/HphI genotypes and alleles were as follow: CC – 0.588, CT – 0.356, TT – 0.056, C – 0.766, T – 0.234. Frequencies of LEP/Sau3AI genotypes and alleles were: AA – 0.630, AB – 0.190, AC – 0.140, BB – 0.015, BC – 0.015, and C – 0.010, A – 0.796, B – 0.117, and C – 0.087.

The study on the reproduction parameters of Arctic foxes was conducted on a farm located in north-eastern Poland, in the years 2000-2002. Three genetic groups were distinguished: group I – Finnish foxes (F), group II – F₁ hybrids (F × P), group III – Polish foxes (P). Finnish foxes (FF – Super blue) were descended from the ones imported from Finland. F₁ hybrids were produced by mating Finnish foxes to Polish ones. Group III were Polish foxes mated within the population. The reproductive activity of males was analyzed on the basis of the number of matings over the breeding season. In the case of females the parameters taken into account were: the percentage of barren females and fecundity, i.e. the number of pups born alive and weaned. It was found that the reproductive activity of Finnish and hybrid males was higher than the activity of Polish males. The percentage of barren females was higher in the group of one-year-olds, compared with the ones used in successive years. The fecundity of Finnish and hybrid females displayed a falling tendency.

The investigations were carried out in the period between October 2002 and April 2004 on 404 cows housed on one of dairy farms of the Wielkopolska region and subjected to milk performance testing with the AT4 method. Data for analysis was from the first six test-days. It was found a positive (i.e. disadvantageous) relationship between average milk yield and days open (p≤0.05). A similar relationship was observed between milk fat content on the test-day preceding the first AI service and days open, and the number of AI services per confirmed pregnancy (p≤0.05). Furthermore, a significantly (p≤0.05) lower milk protein content was found on the first test-day after calving in cows in which days open exceeded 150 days, and in cows in which the number of AI services per conception was greater than 3.

The research aimed at the analysis of influence of birth term and females' age on the reproduction results of common silver foxes (Vulpes vulpes L.). The data included 1155 litters in the years 1997-2003. The analysis of variation for the number of born foxes proved statistically significant influence of the calendar year. In relation to the number of raised animals, it has been proved that the females' age was statistically significant. No statistically significant impact of the whelping season on the analysed traits was noted. The mean number of born puppies was the lowest in one year old vixens (4.36 individuals) and six years old (4.30), while the raised in one year old vixens (3.85 individuals) and two years old (4.07). The highest values were obtained by five yeas old females (4.85 and 4.66, respectively). As far as the whelping season is concerned, little impact on reproduction results was noted. Litters in the earlier births (births up to 10th April) were more numerous (4.49 born and 4.10 raised) in comparison to the late kittenings of females (births in May), (4.24 and 4.01, respectively). The number of born pupies per litter ranged from 1 to 8 animals while the number of raised ranged from 0 to 8 animals. Over 27% of vixens delivered 5 puppies, 22% delivered 4 puppies and 15% delivered 6 puppies. Variability of traits estimated by variability coefficient ranged from 30 to 35% for the number of born and from 30 to 50% for the number of raised animals. The obtained results of the reproduction seem to be very good.

A qualitative assessment of 169 chief breeding studs was conducted in the years 1986-1999 in the horse breeding farms in north-eastern Poland (Liski, Rzeczna, Plękity, Kadyny, Nowa Wioska). The usability of the studs for breeding was evaluated based on a proposed index of stud breeding effectiveness. It formed the basis for a classification of studs in terms of their usability for breeding. Selected breeding studs were also characterised in terms of their ability to pass on the desired functional features onto their offspring.

Limb diseases in ratites represent a problem in the farming. This study was carried out at the Department of Poultry and Ornamental Bird Breeding in Szczecin, Poland, on the co-operating emu and ostrich farms. Based on the observations, the following recommendations have been proposed, which should facilitate proper management of an emu/ostrich farm: (1) as a preventive measure, the legs of the chicks should be tied together for 4-6 days after hatching; (2) the chicks should be provided with enough space to move freely; (3) the ration during the first weeks of life should not much exceed the level of birds' nutritional requirements; (4) against curled toe or toes, corrective splints should applied, tailored to the size of the foot and fastened so as not to impede movement ability; (5) intensive and regular stimulating massages should be applied against myopathy.

Research was done on relations between β-lactoglobulin (LGB), κ-casein (CSN3) genotypes and milk performance traits in the first lactation cows. Milk protein genotypes were identified in population of 856 cows of Black-and-White breed kept in the high milk yielding herd. Cows with LGB AA genotype characterised with the highest milk, fat and protein yields when compared to LGB AB and BB genotypes. Differences between LGB genotypes were statistically significant. Cows with CSN3 BB genotype were superior in milk fat (4.39%) and protein (3.36%) contents when compared to cows of CSN3 AA and AB genotypes. There were no differences between CSN1 and CSN2 polymorphism and milk performance traits stated.