Fatores de risco associados à retenção de placenta em vacas holandesas
Gonçalves, Rodrigo SchallenbergerGuagnini, Fabio de SouzaStorck, Daniel JonasBrose, Mariana de MattosGonzalez, Félix Hilário DiazDalto, André Gustavo Cabrera
Background: Retained placenta (RP) is characterized by a failure to remove the fetal membranes within the first 12-24h after calving. This condition appears to be related to a decrease in neutrophil activity and to the suppression of the immune response in the prepartum period. The specific reasons for some cows to retain the placenta after parturition is stillnot fully understood, but numerous predisposing factors have been related, which may include mechanical, nutritional,infectious and handling factors. The aim of this study was to analyze the occurrence of retained placenta in dairy cowsand to correlate the main predisposing factors related.Materials, Methods & Results: This study was conducted in nine dairy farms located in the Rio Grande do Sul state,Brazil, with an average of 45 lactating dairy cows producing 10,100 kg / dairy cow in a period of 305 days. The total dietfor postpartum cows was estimated to meet or exceed the requirements of dairy cows according to previously establishedguidelines (NRC 2001). A total of 393 calving Holstein cows (126 primiparous and 267 multiparous) were analyzed, ofwhich 203 were kept in a semi-confined production system (free-stall and pasture system) and 190 animals were kept ina free-stall production system. Statistically, the cows were the experimental unit, and the results were analyzed using thePearsons Chi-squared test or Fishers exact test for the comparisons of occurrence of peripartum disorders. In addition,linear and logistic regression models were constructed to determine the effect of the dependent variable on the other indicators, which may be continuous or categorical. Possible correlations of the occurrence of peripartum disorders relatedto production system (free-stall or semi-confined), calving order (primiparous or multiparous), season of the year (heator cold), ECC at calving (1 to 5), calf sex, rectal temperature and dystocia were analyzed. Of the 393 deliveries followedup in...(AU)
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