Test-day records of purebred Tsigai, Improved Valachian and Lacaune ewes were analysed with a general linear model in order to investigate the effects of flock-test day, lactation number, days in milk, litter size and month of lambing. In total, 121 576 (Tsigai), 247 902 (Improved Valachian) and 2 196 (Lacaune) test-day records gathered over the period [1995][1996][1997][1998][1999][2000][2001][2002][2003][2004][2005] were included in the analyses. Average daily milk yields were 0.604 ± 0.279 kg (Tsigai), 0.595 ± 0.243 kg (Improved Valachian) and 1.053 ± 0.475 kg (Lacaune). The significant (P < 0.05) or highly significant (P < 0.01) effects of flock-test day, lactation number (except for Lacaune), days in milk, litter size (except for Lacaune) and month of lambing (either fixed effects or covariates) tested by Fisher's tests were shown. The model explained about 50% of daily milk yield variability, with coefficients of determination as follows: 0.479 for Improved Valachian; 0.487 for Tsigai; 0.537 for Lacaune. Differences in estimated least-squares means were tested using multiple-range Scheffe's tests. A lower daily milk yield was found for the first lactation, single litter and lactations starting in March in comparison with daily milk yield for the second and third lactations (except for Lacaune), multiple litter and lactations starting in January and February (except for Improved Valachian). AliSchaeffer regression adopted for sheep was used for the fitting of lactation curve according to breed.

Test-day records of purebred Tsigai, Improved Valachian and Lacaune ewes were used to analyse the effect of environmental factors on milk fat and protein content. There were 121 424 and 121 158 measurements of fat and protein content for Tsigai, 247 742 and 247 606 measurements of fat and protein content for Improved Valachian and 2 194 measurements of fat and protein content for Lacaune ewes lambing between 1995 and 2005. Overall means and standard deviations for fat and protein content were 7.77 ± 1.606% and 5.94 ± 0.690% for Tsigai, 7.48 ± 1.446% and 5.82 ± 0.620% for Improved Valachian, and 6.97 ± 1.514% and 5.62 ± 0.692% for Lacaune. For fat content, analyses showed a highly significant (P < 0.01) effect of flock-test day and a highly significant (P < 0.01) or significant (P < 0.05) effect of the month of lambing, with the only exception of the month of lambing in Lacaune. The effect of litter size was highly significant (P < 0.01) or significant (P < 0.05) in Improved Valachian and Lacaune. For protein content, analyses showed a highly significant (P < 0.01) effect of flock-test day and a highly significant (P < 0.01) or significant (P < 0.05) effect of the month of lambing. The effect of litter size was highly significant (P < 0.01) in Tsigai and Improved Valachian. Covariates of days in milk which modelled the shape of lactation curves were insignificant, except for Improved Valachian fat content (Ali-Schaeffer regression adopted for sheep). The model explained about 50% of fat and protein variation in the breeds, with coefficients of determination between 0.517 and 0.587 for fat content and between 0.495 and 0.527 for protein content. Fat and protein content were almost equally correlated with milk yield in the three breeds. Lactation curves were constructed on the basis of solutions of a statistical model employed in the analyses.

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Carcass quality and intramuscular fat content of castrates and gilts are compared and a possible dependence of intramuscular fat content on sex and slaughter weight is determined in the pig population of the Slovak Republic. A total of 129 pigs of three different genotypes were included in the experiment. After slaughter, the carcasses were weighed and backfat thickness was measured. On the next day, carcass dissection described by Walstra and Merkus (1995) was determined. Four prime cuts (shoulder, loin, ham and belly) were further dissected to meat, bones and fat with skin. Intramuscular fat content was analysed in a laboratory from the samples (100 g) of musculus longissimus dorsi. The results were statistically analysed using SAS/STAT and a linear model was used to find the dependence of intramuscular fat content. Correlation coefficients between carcass traits and intramuscular fat were also calculated. Sex of pigs, and particularly weight of lean meat and weight of fatty parts had a significant effect on intramuscular fat content (P < 0.0001 and P = 0.0022) while no effect of the genotype and slaughter weight was observed. Significant differences between castrates and gilts were found in almost all observed traits, e.g. average backfat thickness (29.01 vs. 25.56 mm), percentage of meat (52.77 vs. 57.68%), intramuscular fat content (2.49 vs. 2.00%). Generally, the intramuscular fat in the pig population is not sufficient (2.25%), therefore it would be desirable to include this trait in selection strategies in pig breeding.