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ABSTRACT: Protocols to artificially induce cows and heifers into lactation are effective and commercially available in Brazil. However, these protocols demand long hormonal treatments, which is debatable since little research has been done in the subject. To further understand artificial induction to lactation (AIL) protocols, we conducted two experiments. In experiment 1, our objective was to better characterize steroidal profile during an AIL protocol and assess the estradiol (E2) and progesterone (P4) serum profiles of Jersey cows (n=6) subjected to a conventional protocol. In experiment 2, we aimed to compare milk production and serum E2 concentrations of Holstein heifers induced into lactation by the standard AIL protocol (15 injections of E2 and 8 P4 injections) and by a short protocol in which the number of E2 injections and, consequently, the overall dosage of E2, were reduced (8 injections of E2 and 8 P4 injections). We hypothesized that a short AIL protocol (8 days) would be as efficient as the long standard protocol of 15 days. Our hypothesis was confirmed, since we demonstrated that a shorter protocol was able to induce lactation in Holstein heifers without hindering milk production.

This study describes the natural poisoning of goats by Rhododendron simsii in Southern Brazil. Five of eight goats died after ingesting branches of plants, which were pruned and placed near the goats. Clinical signs observed were restlessness, shrill bleating, profuse regurgitation, looking and kicking at the flank, a loss of balance, irregular gait, staggering, and opisthotonos. At necropsy or histopathology affected goats had not showed lesions. Two goats were fed with 21.5g kg-1 bw and 30g kg-1 bw of fresh leaves of R. simsii. Both goats developed signs similar to those naturally affected goats. These findings indicated that R. simsii is highly toxic and lethal to goats.