RESUMO
AIMS To describe milk yield and culling risk in cows diagnosed with left displacement of abomasum (LDA) treated either conservatively, by right flank pyloric omentopexy, or rolling and toggling, compared with normal herdmates from four Chilean dairy herds. METHODS Historical records were obtained from four commercial dairy farms located in Central Chile for cows with a history of LDA between 2010 and 2012, and healthy herdmates. Cows with LDA were categorised into three groups: cows treated with right omentopexy (ST, n=58), cows treated by toggle suturing (TT, n=15) and cows treated conservatively (CT, n=56). Control cows (n=129) were selected from unaffected cows, matched by days in milk (DIM), parity and herd with affected cows. Groups were compared for risk of culling up to 300 DIM and for milk production up to 5 months of lactation using survival and Cox proportional hazard models and mixed models for repeated measures, respectively. RESULTS Compared with cows in the Control group, the risk of being culled up to 300 DIM was 9.1 (SE 0.62) times greater in ST cows, 10.4 (SE 0.68) times greater in TT cows, and 37.3 (SE 0.61) times greater in CT cows (p<0.01). In the first 5 months of lactation, compared with cows in the Control group, mean daily milk production was 23.3 (SE 1.5) kg less in ST cows, 15.3 (SE 1.6) kg less in TT cows, and 30.1 (SE 1.3) kg less in CT cows (p<0.001). CONCLUSIONS AND CLINICAL RELEVANCE Cows in four dairy herds in central Chile diagnosed and treated for LDA produced significantly less milk and had a higher risk of culling than healthy herdmates. Although cows treated surgically or with toggle suture never recovered to the extent of healthy cows, they produced more milk than cows treated conservatively. However, the retrospective nature of the data, the inclusion of only four herds and the non-random allocation to treatments means that these conclusions cannot be extrapolated to the overall dairy cattle population in Chile.
Assuntos
Abomaso/cirurgia , Doenças dos Bovinos/cirurgia , Tratamento Conservador/veterinária , Leite/metabolismo , Gastropatias/veterinária , Animais , Bovinos/fisiologia , Doenças dos Bovinos/fisiopatologia , Feminino , Lactação/fisiologia , Estudos Retrospectivos , Gastropatias/fisiopatologia , Gastropatias/cirurgia , Suturas/efeitos adversos , Suturas/veterináriaRESUMO
The objective was to describe the relationship between concentration of serum nonesterified fatty acids (NEFAs) at calving and the incidence of periparturient disorders in Chilean Holstein dairy cows (Bos taurus). The study was conducted at two dairies (central Chile) with 700 milking cows each and similar management. Between July 2006 and March 2007, 350 cows were selected, and concentrations of serum NEFAs were determined at calving. The incidence of milk fever (MF), retained fetal membranes (RFMs), metritis, and clinical mastitis from calving to 100 d in lactation were consistently recorded. The relationship between concentration of serum NEFAs at calving and the incidence of periparturient diseases was determined using logistic regression. The main explanatory variable was concentration of serum NEFAs at calving. The incidence of MF, RFM, metritis, and mastitis was 5.4%, 15.6%, 10.8%, and 14.4%, respectively. There was no association between concentration of NEFAs at calving and the incidence of these conditions when the median value of NEFAs (0.9 mEq/L) was used as a cutoff. However, when the 75th percentile (1.2 mEq/L) was used as the cutoff, cows with values <1.2 mEq/L were 0.45 and 0.32 times as likely to develop clinical mastitis and MF, respectively, compared with cows with values >or=1.2 mEq/L. When the 90th percentile (1.6 mEq/L) was used as a cutoff, cows with values <1.6 mEq/L were 0.25 times as likely to develop clinical mastitis compared with cows with values >or=1.6 mEq/L. As a continuous variable, for every 0.1 mEq/L increment in NEFAs at calving, cows were 1.11 times more likely to experience clinical mastitis. In conclusion, cows with NEFA concentrations >or=1.2 mEq/L had a higher incidence of clinical mastitis and MF than that of cows with values <1.2 mEq/L.