Author(s): OLIVEIRA, C. S.; DIAS, H. R. S.; CAMARGO, A. J. dos R.; MOURÃO, A. M.; FEUCHARD, V. L. da S.; MULLER, M. D.; BRANDÃO, F. Z.; NOGUEIRA, L. A. G.; VERNEQUE, R. da S.; SARAIVA, N. Z.; CAMARGO, L. S. de A.

Summary: Global warming poses signiî?±cant challenges to the î?–ertility oî?– tropical dairy cattle. One promising approach to mitigate heat stress eî?–î?–ects on reproductive function and reduce the carbon î?–ootprint is the use oî?– integrated livestock-î?–orest (ILF) systems. The aim oî?– this study was to investigate the effects of two different systems, namely Full Sun (FS) and ILF, on maternal hyperthermia and oocyte quality oî?– Holstein and Girolando heiî?–ers during the tropical summer season. The temperature-humidity index (THI) data revealed intense heat stress during the experiment. Both the system (P<0.01) and the breed (P<0.01) î?–actors had a signiî?±cant impact on vaginal temperature, being hyperthermia more pronounced in the FS system and in the Holstein breed. Over the î?±ve time points collected at a 33-day interval, we observed distinct patterns for ILF (P=0.65) and FS (P<0.001) systems, suggesting an adaptive response in animals kept in FS systems. Furthermore, oocyte quality assessment revealed an eî?–î?–ect oî?– the system î?–or oocyte diameter (P<0.001) and levels oî?– IGFBP2 (P<0.001), and caspase 3 levels showed a decrease in ILF compared to FS î?–or both Holstein (P<0.001) and Girolando (P<0.001) breeds. Collectively, these parameters indicate that oocyte quality during the summer months was superior in animals maintained in the ILF system. In conclusion, the ILF system demonstrated promising results in attenuating maternal hyperthermia and mitigating its eî?–î?–ects on oocyte quality. Additionally, our observations suggest that animals in the FS system may exhibit an adaptive response to heat stress.

Publication year: 2024

Types of publication: Journal article

Unit: Embrapa Dairy Cattle

Keywords: Bem-Estar, Bovino, Estresse térmico, IPF, Marcador Molecular