The aim of present study was to find the dependence between chinchilla farm size and achieved reproduction indices. Results were collected from three groups of farms: M – small (up to 50 females), S – medium (50-100 females in herd), D – large (over 150 females). In total, 2743 litters originating from 630 chinchilla females of standard race and performed in 1999-2003 on 8 farms of southern Poland were analyzed. Following items were examined: litter population at the birth and weaning, fall number, efficiency of progeny rearing, mortality per a litter, and pregnancy interval. Significant differences were recorded referring to the number of reared litter; the largest number of animals reared per a litter (1.77 kids per litter) occurred on medium farms, the smallest (1.63 kids per litter) on large farms. The lowest number of young falls during rearing was observed on small and medium farms (0.23 and 0.19 kids per litter, respectively), as well as the best rearing efficiency (88.2 and 89.8, respectively). Farm size did not affect the distribution of pregnancy intervals.

Object of investigations one was results of hygienic and chemical and physical estimation milks to put away to one from cooperative of a creamery in Kujawy and Pomerania province. To analysis we subjected results from 5235 monthly deliveries of milk in period from 2000 to 2003 year. Milk higienic parametrs – total number bacterial count (TBC) and number of somatic cells (SCC) and chemical composition – content of fat and protein in milk and physical factors- acidity and temperature one investigated in dependences from season of purchasing centre and sizes monthly deliveries of milk to cooperative. One introduced also classification of raw milk in dependences from year of purchasing centre, of season and sizes monthly deliveries. One showed influence of season of purchasing centre and sizes monthly deliveries on investigated features of milk. One ascertained improvement of milk hygienic quality. Shows o this height of participation of milk in class Extra and gradual eliminating from purchasing centre of lower classes.

Four complete diets in grower type were used in the experiment: (1) cereal-soybean control diet, (2) cereal- -soybean diet containing 0.01% of sodium saccharinate, (3) cereal-soybean diet containing 15% of rapeseed meal and (4) diet which addition of rapeseed meal (15%) and sodium saccharinate (0.01%). Feed preference test was carried out on 16 (8 female and 8 barrows) individually kept (in flat-deck cages) young growing pigs (crosses of ♀ Polish Landrace x ♂ Duroc). The pigs were selected by the analogue method (on the basis of sex, body weight and litter of origin), and divided into four feeding groups. Each of them consisted one element in experiment by Latine Square method. Diets were fed to animals 4 time per day, at 8.00, 11.00, 14.00 and 17.00 h, by a single stimulus method. The animals had free access to one of experimental, peletted diet by 20 minutes in the time of each one feeding. Really feed intake time and the level of feed intake were controlled. It was not statistically stated, that addition of sodium saccharinate have an influence on diet palatability in young growing pigs feeding. However, there was confirmed for tendency to lower intake of diet containing 15% of rapeseed meal. During a whole 8-day feed preference test an average intake of diets per one pig in the time of one feeding it was: (1) 347, (2) 350, (3) 335 and (4) 351 g , respectively.

The experiment of slaughter value and quality meat was performed on Polish White goat kids aged 7 months. Goat kids with similar body weights, selected by the analogue method, were allocated to two groups: I – non castrated goat kids, II – castrated 28 days goat kids. It was found that carcasses of castrated goat kids contained more fat. Meat from non-castrated goat kids had a higher dry matter and protein content. The results of sensory analysis indicated very high eating quality of meat from both castrated and non-castrated goats. Castration of goat kids is unnecessary.

The aim of the study was to determine the effect of different light intensity on whelping interval, number of litters per year and a total number of born chinchillas per year. The studies took place in 2001 through 2003. The analysis involved 480 standard chinchilla. In chinchilla sheds, 12-hour light regime was applied; average illumination was 5 W∙m^-2, while intensity was 0-90 lx. In 2001, at a selected part of the shed, new lamps were installed, which were of higher power, i.e. 10 W∙m^-2, with 91-270 lx intensity. The whelping interval decreased with an increase in light intensity. The highest number of litter and total offspring from female per year were obtained under the higher range of light intensity. The range of light intensity between 150 and 240 lx was the most optimal.

The purpose of the experiment was to estimate the possibility of substitution of antibiotic for dried brewery’s yeast (Saccharomyces cerevisicae). The 540 weaners were chosen to experiment then divided into three experimental groups. The animals were fed with the same mixture differing with kind of used additive. First group (control) fed mixture supplemented with antibiotic (20 ppm of avilamycin). The animals from groups 2nd and 3rd fed mixture with 1 or 2.5% of dried yeast. The experiment was carried at the period from 45 day of life to day in which animals reached 30 kg of body weight. The rate of growth, feed intake and health condition of the animals were controlled. The weaners from group 3rd (2.5% of yeast) had similar rate of growth as animals from control group (20 ppm of avilamycin). The higher concentration of protein and albumin in serum and lower level of urea were due to the better feed utilization especially protein in the groups 2nd (1% of yeast) and 3rd (2.5% of yeast). Application of higher dried brewery’s yeast dosis caused that there the introductory signs of immunosuppresion – higher hemoglobin, erythrocytes and leucocytes concentrations were observed. The antibiotic in the mixture for weaners could be replaced dried brewery’s yeast at amounts 1-2% into the starter mixture with a good zoohigienical condition.

The aim of the study was to evaluate carcass slaughter value of pure-bred and cross-bred beef bull calves. The experiment was carried out on Charolaise (CHL) bull calves and cross-bred bull calves dammed by Hereford and Simmental cows and sired by Charolaise bulls. After slaughter, the carcasses were evaluated according to the EUROP system for lean content and fattiness. Hot carcasses were weighed and measured. Right halves of the carcasses were dissected. The carcasses were mostly classified as E or U for leanness and 1st or 2nd class of fattiness. The best results for most parameters were achieved be SIM x CHL crossbreds, which had the highest body and carcass weights and, consequently, the largest carcass sizes and weights of most cuts, particularly the very valuable round. The crossbreds have also achieved the highest slaughter yields.

The analysis of reproduction traits was carried out at the Fur Animal Farm number B-256 in 2001. It has been proved that one year old vixens, in comparison to the two years old and older, had later mean term of measure of the vaginal mucus resistance in 0-Day (that is around 28th march) and the smallest resistance expressed in ohm (698.4). The highest fecundity (the number of born and weaned puppies) had three, four and five years old vixens. The vixens with early estrus irrespectively of the type of curve had a higher value of the uterus vaginal mucus resistance expressed in ohm and the calculated correlation was statistically significant or very significant (r_xy= from -0.269^xx to -0.478^xx). No significant correlation has been noticed between mucus resistance in 0-Day (in ohm) and the number of born puppies in relation to the age of a vixen and type of the mucus resistance curve.

The purpose of this experiment was to determine the influence of Cu chelated with lysine in drinking water on physical parameters and mineral composition of tibia in turkeys. The research was carried out on 2 groups of heavy type turkeys BIG-6 (100 birds each). All the birds were kept under regular environmental conditions, according to the accepted norms of industrial fattening. Turkeys were fed standard complete mixtures and had unlimited access to water. The turkeys of experimental group received the supplement of Cu chelated with lysine in drinking water at the concentration of 10mg Cu∙dm^-3 H₂O. The research showed that the final body weight of experimental turkeys was higher compared to the control birds. The difference was confirmed statistically at p≤0.05. The addition of Cu-bioplex decreased the fresh bone weight by 14.1% and the air dry matter of bone by 8%. The share of tibia bones in the experimental turkeys body weight was decreased by 20.5% compared to the control group. The durability of tibia bones in turkeys given chelate was lower by 6.7% than the value describing the control group. The supplement of Cu-biplex had no significant effect on the content of tibia crude ash but it decreased both Ca and P concentrations and increased the content of Mg whereas the content of Cu was the same in every group.

Genetic parameters of milk were estimated on the grounds of the number of 103 264 testing lactations by using the REML-Animal Model. The maximum amount of h² (about 0.35) were noticed for milk’s productivity, lactose and protein in the middle of lactation, for protein and fat – about 260 day of lactation but h² LnSCC during the all process of lactation was 0.18. The highest amount of repeatability’s coefficients were found in the first and the last days of lactation. During the all process of lactation, correlations between productivity of milk and productivity of protein and lactose were high (about 0.9), between productivity of milk and consistence of fat and protein were negative. The studies showed that correlations between productivity of milk and productivity of LnLKS were fluctuating from 0.2 in the 50 day of the lactation, to – 0.1 in the second half of lactation.

On the basis of 3457 cows that were born between 1966 and 1999 in ZZD IZ Pawłowice, the reasons of a cull were analysed. No dependences between the age of the first calving and the longevity of cows were found. The main reasons of the cull were the reproduction problems, especially infertility. The grade of the reasons of a cull caused by the fertility problems and the longevity highly depends on the rate of hf genes.

The aim of the present study was to analyze the yield and contents of milk fat and milk protein, and to determine the correlations between these parameters on the basis of 5471 lactations, including 1955 lactations after the first calving, 1228 after the second calving, 914 after the third calving and 1374 after more than three calvings of Black-and-White cows (with a higher protein content of milk than in the domestic population), taking into account the milk protein to milk fat ratio. Depending on this ratio the cows were divided into three groups, i.e. <0.8, 0.8-0.9, and >0.9. Significant correlations were observed between the contents of milk fat and milk protein in these groups. It was found that an increase in the protein to fat ratio from <0.8 to 1 is accompanied in successive lactations by a decrease in the milk yield and the contents of fat and protein. This indicates that it is difficult to maintain high productivity of cows and a well-balanced protein to fat ratio.

Changes in the pedigree structure of mares, bred in the years 1986-1999 at the selected stud farms of the north-eastern Poland, as well as changes in their biometric parameters were analysed. Over the 14 years of breeding at the Plękity, Liski, and Nowa Wioska Stud Farms, an increased percentages of mares with medium and high shares of Thoroughbred were observed in the structure of the mare stock investigated. In the Nowa Wioska and Kadyny Stud Farms, a substantially higher share of Hanoverian blood was also observed. In the stud farms under scrutiny, the biometric parameters of the mares examined also changed. Moreover a significant correlation between biometric parameters of the, mares and the increasing share of Thoroughbred and Hanoverian blood in their pedigree was found.