Effect of concentrate supplementation on calf weight, pregnancy and body condition of cows from Lower Paraguayan Chaco

Abstract

The objective of the study was to evaluate the effect of concentrate supplementation of suckling calves on their weight gain, as well as the pregnancy percentage and body condition of the cows, which was carried out in an establishment located in the Department of Presidente Hayes, Lower Paraguayan Chaco. Thirty unweaned calves from multiparous cows between 2 and 3 months of age, were used. They were grouped into two treatments (T) of 15 calves and 15 cows for each treatment (T1: calves not supplemented and T2: calves supplemented), which grazed on a native pasture during the assay. The supplement consisted of a concentrate with 20% crude protein and 3 Mcal/kg of metabolizable energy, which was offered for 120 days. On each T, a Brangus bull was assigned to service the cows for 70 days. The average daily weight gain of the calves was 0.464 and 0.708 kg for T1 and T2, respectively, the difference being statistically significant (p<0.05). On the other hand, the pregnancy percentage was identical in both groups (7%). However, the number of cows with the highest final body condition (FBC3) increased in T2. It can be concluded that the most important effect was the improvement in the daily weight gain of the calves that received the supplementation and the increase in the number of cows with FBC3.