Concentración plasmática de zinc en vacas de cría de la cuenca deprimida del río Salado

Zinc (Zn) is an essential micromineral and its deficiency can affect the productive and reproductive efficiency in cattle. A multicenter observational study was carried out to evaluate Zn status in breeding cows at Salado River Basin (Buenos Aires, Argentina). The study included 110 cow-calf operations, in which blood samples (n = 1078 cows) were collected and analyzed by using atomic absorption spectrophotometry. Cows were classified according to their plasma Zn concentration values as physiologically adequate (≥ 90 μg/dl), marginal (between 80 to 89 μg/dl) and deficient (<80 μg/dl). A descriptive statistical analysis was performed using the SAS program MEANS procedure. The average plasma Zn concentration was 102.8 ± 16.4 μg/dl and 31.4 % of the cows in each herd showed marginal or deficient values. The highest percentage of marginal or deficient cows was recorded in winter (47.7 %), while the lowest percentage was recorded in autumn (21.3 %). These results show that there is Zn deficiency in cow-calf operations of Salado River Basin.