Effect of health status on fattening performance in young crossbred polish Holstein‐Friesian × Limousin Bulls and steers

The aim of this study was to determine the effect of disease incidence on selected parameters of cattle fattening performance and carcass quality, and the fatty acid profile of beef. The experimental materials comprised 16 bulls and 16 steers, Polish Holstein‐Friesian × Limousin crossbreeds (including 10 healthy and six treated animals of each category). At 5 weeks of age, bloodless castration was carried out using a rubber elastrator. The calves were fed milk replacer provided in automatic feeding stations. Until 540 days of age, the animals were fattened in an Animal Research Laboratory equipped with the Roughage Intake Control (RIC) system (Insentec, the Netherlands). In comparison with healthy (untreated) bulls and steers, sick (treated) animals had lower average body weight at 180 days of age, by 37 kg (P ≤ 0.05) and lower average final body weight at 540 days of age, by 56 kg (P ≤ 0.05). Sick animals were characterized by lower feed intake and worse feed efficiency (not statistically significant differences). Hot carcass weight reached 318 kg in healthy animals and 258 kg in treated bulls (P ≤ 0.05). In treated steers, the percentage of lean meat and bones in the three‐rib section was higher and the percentage of fat was lower, compared with their healthy counterparts (P ≤ 0.01). There was a category × health status interaction for carcass tissue composition. There were no significant influences of type of sickness on analyzed traits. In comparison with healthy steers, intramuscular fat of Musculus longissimus dorsi (MLD) from treated steers had significantly (P ≤ 0.05) higher concentrations of polyunsaturated fatty acids (n‐6 and n‐3) and a lower content of conjugated linoleic acid.     

Heavy metals in horse blood, serum, and feed in Minas Gerais, Brazil

Pollution is a subject of worldwide concern and discussion and various areas of science are seeking to integrate their knowledge in an attempt to improve understanding of the harmful effects of modern human activities. Thus, the objective of the current study was to assess the potential for using the horse as a bio-indicator of environmental pollution. Blood and serum samples from 120 horses from locations with different degrees of urbanization and industrialization and the feeds used for these animals were analyzed to determine their heavy metal (Cd, Pb, Ni, Cu, and Zn) content. The data obtained were compared. The results did not show increases in heavy metal concentration in the blood and serum of the horses with the intensification of urbanization and industrialization around the farms. Only Cd, as determined in the blood of the animals, showed a certain potential for using horses as bio-indicators of environmental pollution. The data for sex, age, and chemical composition of the foodstuffs supplied to the animals were not determinants in explaining the variation in the concentrations of heavy metals observed.     

Comparison of Puccinia graminis f.sp. tritici from South America and Europe

Twenty isolates of Puccinia graminis f.sp. tritici from South America were compared with 19 from Europe using virulence, isozymes and random amplified polymorphic DNA (RAPD) markers. The isozyme and virulence patterns for these isolates were also compared with those of 11 isolates representative of the common race clusters in North America. All three types of marker showed a level of similarity between the South American and European isolates comparable with that between isolates from the same continent. The average similarity coefficients between the South American and European isolates were 0.65 for virulence, 0.67 for isozymes, and 0.70 for RAPD markers. Among South American isolates the values were 0.63 for virulence, 0.64 for isozymes and 0.72 for RAPDs. For the South American and European isolates, correlation between the similarity matrices based on RAPDs and on isozyme markers, respectively ( r  = 0.52), was higher than that between the RAPD and virulence matrices ( r  = 0.32) or between isozyme and virulence matrices ( r  = 0.16). The North American isolates had a comparable level of similarity for virulence and isozymes to both the South American and European populations. There was no clear distinction between the South American, North American and European isolates, which is consistent with the hypothesis that these populations may have had a common origin.