Behavioral, productive, reproductive and thermoregulatory performance of lactating 3/4 and 7/8 Holstein/Gir cows
The aim of this study was to examine the behavioral, productive, reproductive and thermoregulatory performance of 3/4 and 7/8 Holstein/Gir (HG) dairy cows to identify which genetic composition suffers the least heat stress. A completely randomized design was adopted involving 20 multiparous, lactati...
| Autores: | , , , , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2021 |
| País: | Brasil |
| Institución: | Universidade Estadual de Londrina (UEL) |
| Repositorio: | Semina. Ciências Agrárias (Online) |
| Idioma: | inglés |
| OAI Identifier: | oai:ojs.pkp.sfu.ca:article/40378 |
| Acceso en línea: | https://ojs.uel.br/revistas/uel/index.php/semagrarias/article/view/40378 |
| Access Level: | acceso abierto |
| Palabra clave: | Ambience Dairy production Thermotolerance. Ambiência Produção Leiteira Termotolerância. |
| Sumario: | The aim of this study was to examine the behavioral, productive, reproductive and thermoregulatory performance of 3/4 and 7/8 Holstein/Gir (HG) dairy cows to identify which genetic composition suffers the least heat stress. A completely randomized design was adopted involving 20 multiparous, lactating crossbred cows from a dairy farm located in the municipality of Turvânia - GO, Brazil. During the experimental period, data on behavioral, productive, reproductive and thermoregulatory traits were collected every 15 days. Bioestat (5.0) statistical software was used for statistical analysis. The mean temperature-humidity index, ambient temperature and relative humidity obtained throughout the experimental period were 74.45, 30.51 ºC and 63.64%, respectively. In terms of reproductive performance, there was a significant difference (p < 0.05) between the genetic compositions for the time from calving to first service, with a longer period shown by the animals with greater Holstein breed genetic composition. Service period and calving interval differed significantly (p < 0.05) during the experimental period between the genetic compositions. A significant difference (p < 0.05) was also detected between the compositions for respiratory rate, with higher values observed in the animals with higher European genetic composition. Benezra thermal comfort index also differed significantly (p < 0.05), with the 7/8 HG animals showing a higher value. Lactating cows with a 7/8 HG genetic composition achieved better results in milk production, whereas those with 3/4 HG genetic composition showed superiority in milk fat composition and reproductive and thermoregulatory performance, indicating greater adaptation to the climatic conditions of the region. |
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