Predictive potential of activity and reticulo-rumen temperature variation for calving in Gyr heifers (Bos taurus indicus)

Autor(es)

Vicentini, Rogerio Ribeiro ^[1] ; Bernardes, Priscila Arrigucci ^[2] ; Ujita, Aska ^[3] ; Oliveira, Andre Penido ^[4] ; Lima, Maria Lucia Pereira ^[5] ; El Faro, Lenira ^[5] ; Sant'Anna, Aline Cristina ^{[1, 6]}

Afiliação do(s) autor(es)

^[1] Univ Fed Juiz de Fora UFJF, Nucleo Estudos Etol & Bem Estar Anim NEBEA, Juiz De Fora, MG - Brazil

^[2] Univ Fed Santa Catarina UFSC, Dept Zootecnia & Desenvolvimento Rural, Florianopolis, SC - Brazil

^[3] Univ Sao Paulo, Fac Zootecnia & Engn Alimentos FZEA, Sao Paulo - Brazil

^[4] Empresa Pesquisa Agr Minas Gerais EPAMIG Oeste, Uberaba, MG - Brazil

^[5] Agencia Paulista Tecnol Agronegocios, Secretaria Agr & Abastecimento APTA SAA, Inst Zootecnia IZ, Ctr Avancado Pesquisa Bovinos Corte, Sao Paulo - Brazil

^[6] Univ Fed Juiz de Fora UFJF, Dept Zool, Nucleo Estudos Etol & Bem Estar Anim NEBEA, Juiz De Fora, MG - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Thermal Biology; v. 95, JAN 2021.
• Citações Web of Science: 1

Resumo

Factors related to the thermal physiology and activity of Zebu animals close to calving are still unknown. The aims of this study were 1) to describe the pattern of reticulo-rumen temperature and activity variation in nullipamus Gyr heifers close to calving, and 2) to evaluate the predictive potential of these traits for calving in Gyr heifers. Forty pregnant Gyr heifers that had calved between August and December 2017 at the Gettilio Vargas Experimental Station, Empresa de Pesquisa Agropecunria de Minas Gerais (Epamig), Brazil, were used. The animals received a rumen bolus to monitor reticulo-rumen temperature (Trr) and activity (Act) at intervals of 10 min. Mixed linear models were used. A decrease in Trr and an increase in Act were observed on the days preceding calving. Differences in Trr and Act were more evident during the final 21 and 11 h previous to calving compared to 14 days before calving, measured at the same time of day. There was a decrease of about 0.20 degrees C in Trr at the time of calving when compared to baseline (14 days before calving measured at the same time of day). Environmental variables, such as temperature and air humidity, as well as biological factors such as circadian rhythm, may influence the interpretation of the data. In conclusion, variations exist in the Trr and Act of Gyr heifers in the hours before calving, which is preceded by a decrease in Trr and an increase in Act. Particularities in the thermal physiology of Zebu cattle must be considered when prediction devices previously validated only for European breeds are used. (AU)

• Processo FAPESP: 15/24174-3 - Estudo de características ligadas ao estresse, temperamento e à reprodução em fêmeas da raça Gir Leiteiro
• Beneficiário: Lenira El Faro Zadra
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 18/19975-5 - Estudos de características complexas em bovinos de leite
• Beneficiário: Priscila Arrigucci Bernardes
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado