Prejuízos causados pela mastite em ovelhas Santa Inês / Damages caused by mastitis in Santa Inês Brazilian sheep breed

A mastite tem causado grandes prejuízos em criações de ovinos para corte no Brasil, onde o número de cordeiros nascidos e desmamados é de enorme importância econômica para o sistema de produção. O objetivo deste trabalho foi quantificar esses prejuízos em uma propriedade com ovinos da raça Santa Inês, em sistema semi-intensivo de produção, no Estado de São Paulo. Foram feitos exames clínicos, o Califórnia Mastitis Test (CMT), e as colheitas de leite para exame microbiológico das ovelhas na segunda semana de parição e no desmame. No mesmo dia das colheitas de amostras de leite, os cordeiros foram pesados, bem como no dia do nascimento. Quarenta e uma ovelhas pariram 55 cordeiros (taxa de natalidade 1,34) na estação de parição de 23/10/2008 a 4/1/2009. Destes, 20 (36%) morreram, 14 (70%) nas primeiras duas semanas de vida, e seis (30%) antes do desmame, que ocorreu em torno de 70 dias. 70% (14) das mortes foram atribuídas à condição de mastite da ovelha, e 30% (6) a outras causas, principalmente pneumonia. O ganho de peso diário do nascimento ao desmame de cordeiros filhos de ovelhas com mastite, em pelo menos uma glândula mamária, foi inferior (P < 0,10) ao de cordeiros filhos de ovelhas sadias. Das amostras positivas no exame microbiológico, 85,8% estavam positivas para bactérias do gênero Staphylococcus.

In meat sheep herds in Brazil, mastitis has provoked many damages, causing mortality and decreasing the numbers of lambs born and weaned, posing heavy economic impacts for the production system. The objective of this study was to quantify the damages caused by mastitis in a Santa Inês breed herd, reared in a semi-intensive production system, in São Paulo State, Brazil. Clinical exams were conducted and the California mastitis test was carried out, and milk samples were taken from the ewes for microbiological assay. The lambs were weighed at birth and on the days when the milk samples were taken. Forty-one ewes gave birth to 55 lambs (birth rate of 1.34) during the parturition season from 23 October 2008 to 4 January 2009. Twenty (36%) of them died, 14 (70%) in the first 2 weeks following birth, and 6 (30%) before weaning, which occurs at about 70 days. A total of 70% (14) of the deaths were imputed to the occurrence of mastitis in the respective ewe, and 30% (6) to other causes, mainly pneumonia. Mastitis decreased the average daily gain of the lambs from birth to weaning (P < 0.10). Most of the positive microbiological samples (85.8%) where positive for Staphylococcus spp.

Performance and nematode infection of ewe lambs on intensive rotational grazing with two different cultivars of Panicum maximum.

The daily live weight gain (DLWG), faecal nematode egg counts (FEC), and packed cell volume (PCV) of Suffolk, Ile de France and Santa Inês ewe lambs were evaluated fortnightly for 56 days in the dry season (winter) and 64 days in the rainy season (summer) of 2001-2002. The animals were distributed in two similar groups, one located on Aruana and the other on Tanzania grass (Panicum maximum), in rotational grazing system at the Instituto de Zootecnia, in Nova Odessa city (SP), Brazil. In the dry season, 24 one-year-old ewe lambs were used, eight of each breed, and there was no difference (p > 0.05) between grasses for DLWG (100 g/day), although the Suffolk had higher values (p < 0.05) than the other breeds. In the rainy season, with 33 six-month-old ewe lambs, nine Suffolk, eight Ile de France and 16 Santa Inês, the DLWG was not affected by breed, but it was twice as great (71 g/day, p < 0.05) on Aruana as on Tanzânia grass (30 g/day). The Santa Inês ewe lambs had the lowest FEC (p < 0.05) and the highest PCV (p < 0.05), confirming their higher resistance to Haemonchus contortus, the prevalent nematode in the rainy season. It was concluded that the best performance of ewe lambs on Aruana pastures in the rainy season is probably explained by their lower nematode infection owing to the better protein content of this grass (mean contents 11.2% crude protein in Aruana grass and 8.7% in Tanzania grass, p < 0.05) which may have improved the immunological system with the consequence that the highest PCV (p < 0.05) observed in those animals.