Volume 11(3), 2012

Abstract. The aim of the study was to compare Red Angus and Hereford primiparous cows based on the age at first calving and body weight as well as to compare some indices of fertility, lactation yield and selected zoometrical measurements. The research was conducted on the farm located in the West Pomerania Province. The age at first calving (AFC) and the variability of body weight were similar for both breeds. The primiparous Hereford cows were characterized by significantly (P ≤ 0.01) higher estimated lactation yield (2054.9 kg) compared with primiparous Angus cows (1992.8 kg) and significantly (P ≤ 0.01) higher values of zoometrical parameters: hip height (suitably: 135.5 cm i 132.5 cm) and chest girth (suitably: 197.0 cm and 191.6 cm).

Abstract. The aim of this study was to determine plasma concentrations of progesterone and testosterone in blood collected on different dates from pregnant mink of different color varieties. Blood was collected from fourteen pregnant female mink: seven Wild-type Standard Brown females and seven Black females, so called short NAP or Velvet. Blood was collected seven times – the first time before the matings, and the last time in about three weeks before birth. Hormone concentrations were determined by fluorescence immunoassay using the Delfia kits (PerkinElmer, Turku, Finland). Plasma concentrations of progesterone and testosterone differed significantly between collection dates. Significant differences in the concentrations of the hormones were determined also in relation to the color variety of pregnant mink. The concentrations of both studied hormones in the blood plasma of pregnant mink were positively correlated.

Abstract. The aim of this study was to analyze the effect of gestational length and multiplicity of mating encounters on selected reproductive parameters within several color varieties of the mink. The material comprised the breeding results of 1285 American mink females of three color varieties: Sapphire, Silverblue, and the Scanbrown. The highest fertility and the highest number of live born and weaned per litter were achieved by Silverblue females.Within all the analyzed gestational length intervals in each color variety, the pregnancies with a length of 45 to 55 days were dominant (78.1% for Sapphire, 75.78% for Silverblue and 64.75% for Brown), while the lowest percentage (3.17% for Sapphire, 6.88% for Silverblue and 3.25% for Brown) represented the pregnancies lasting up to 44 days. The study shows that with an increase in the length of gestation litter sizes become smaller, which is consistent with reports of other authors conducting similar research on this group of animals.We observed an increase in the average litter size with an increase in the number of mating encounters within all analyzed mink color varieties.

Abstract. The experiment was carried out on two groups of fatteners crossbreds Pul x PLW (group I – 20 heads) and PL x PLW(group II – 20 heads). The fattening was conducted for 99 days in a period when the average body weight of pigs ranged from 30.5 to 105 kg and it was divided into two periods that lasted 53 and 46 days, respectively. Pigs of both groups were fed with the same mixtures based on wheat and barley (first period of fattening – 12.99 MJ ME, 170 g crude protein, 9.60 g lysine) and only barley (second period of fattening – 12.49 MJ ME, 150 g crude protein, 8.37 g lysine) supplemented with protein concentrate. The PL x PLWpigs had better daily weight gain, feed conversion ratio and were slightly more fleshiness and less fatty compared to Pul x PLW pigs. Pigs of group I, despite worse results of slaughter value, were characterized by better meat quality and more crude protein and intramuscular fat in longissimus muscles. The fat contained significantly (P ≤ 0.05) more α-linolenic acid (C18:3). longissimus and adductor muscles in the I group had better water holding capacity and lower drip loss, but significance difference only in longissimus muscles were noticed.

Abstract. Seven observations of European bison were made between April and July 2009 (from 6.00 to 18.00) at the Municipal Zoological Garden of the Sea Coast in Gdańsk-Oliwa (8 animals) and at the Polish Fauna Garden of Forest Culture and Leisure Park “Myślęcinek” in Bydgoszcz (4 animals). During 12-hour observations, the European bison from zoological gardens spent 31% of their time feeding, 47% standing and moving, and 22% lying down (showing preference for left lateral recumbency), although no statistically significant effect of the animals’ living environment (garden) was found. The age and sex of European bison had a statistically significant effect on the amount of time spent performing basic activities. The longest standing and moving times were observed in calves, while males spent most of their time resting–lying. In both zoological gardens, the increased feed intake activity was closely associated with feeding time, and the number of European bison resting lying was found to increase immediately after feed intake activity.

Abstract. The objective of this study was to determine the effect of parity on the fatty acid profile of milk from 42 high-yielding cows, including 15 primiparous cows, 15 cows in their second lactation and 12 cows in their third lactation. Milk yield was evaluated and milk samples (462 in total) were collected between lactation days 6 and 60, at five-day intervals. The concentrations of 43 fatty acids were determined by gas chromatography in extracted fat. Cows in their third lactation were characterized by the highest milk yield – over 305-day lactation, they produced 13,160 kg of milk on average. Milk from primiparous cows had the most desirable fatty acid profile. It contained more (by ca. 12–17%) n-3 fatty acids and less (by 2.89–5.46%) fatty acids that adversely affect human health, compared with the other groups. Among essential fatty acids, differences were noted with respect to CLA (+9.5–9.8%), LNA (+12.7–18.7%) and DHA (+21–23%) to the advantage of the milk fat of primiparous cows.

Abstract. The study was carried out in 2006–2011 in a farm located in the Kujawsko-Pomorskie province and keeping about 290 Polish Black-and-White Holstein-Friesian cows with a mean yield of almost 11,000 kg milk. GLM and FREQ procedures of the SAS package were used for statistical analysis. The lifespan and length of productive life of high-yielding cows tended to decrease, with an alarming tendency for the increasing proportion of cullings among young cows, especially in the first lactation. Culling intensity was found to be high (32%). The proportion of voluntary culling decisions by the breeder, which include selling for further breeding, low productivity and old age, decreased from about 6% in 2006–2007 to about 2% in the following years. High-yielding cows were mainly culled for infertility and reproductive diseases (35.9%), diseases of the locomotor system (15.1%), udder diseases (13.1%), and metabolic and digestive diseases (12.9%).