Evaluation of Ingestive Behavior, Ruminal and Blood Parameters, Performance, and Thermography as a Phenotypic Divergence Markers of Residual Feed Intake in Rearing Dairy Heifers
Mayara Campos Lombardi,
Hilton do Carmo Diniz Neto,
Sandra Gesteira Coelho,
Fernanda Samarini Machado,
Luiz Gustavo Ribeiro Pereira,
Thierry Ribeiro Tomich,
Mariana Magalhães Campos
Affiliations
Mayara Campos Lombardi
Department of Animal Science, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 30161-970, MG, Brazil
Hilton do Carmo Diniz Neto
Department of Animal Science, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 30161-970, MG, Brazil
Sandra Gesteira Coelho
Department of Animal Science, Veterinary School, Universidade Federal de Minas Gerais, Belo Horizonte 30161-970, MG, Brazil
Fernanda Samarini Machado
Brazilian Agricultural Research Corporation, Empresa Brasileira de Pesquisa Agropecuária-Embrapa Gado de Leite, Juiz de Fora 36038-330, MG, Brazil
Luiz Gustavo Ribeiro Pereira
Brazilian Agricultural Research Corporation, Empresa Brasileira de Pesquisa Agropecuária-Embrapa Gado de Leite, Juiz de Fora 36038-330, MG, Brazil
Thierry Ribeiro Tomich
Brazilian Agricultural Research Corporation, Empresa Brasileira de Pesquisa Agropecuária-Embrapa Gado de Leite, Juiz de Fora 36038-330, MG, Brazil
Mariana Magalhães Campos
Brazilian Agricultural Research Corporation, Empresa Brasileira de Pesquisa Agropecuária-Embrapa Gado de Leite, Juiz de Fora 36038-330, MG, Brazil
The objectives of this study were: (1) to identify and rank phenotypically divergent animals for residual feed intake (RFI) regarding their efficiency (high: HE or low: LE); (2) to evaluate their relationships with ingestive behavior, ruminal and blood parameters, performance, and infrared thermography; and (3) to determine if such measurements can be used as feed efficiency markers in rearing dairy heifers. Thirty-eight heifers, 143 d ± 4 (Mean ± SD) of age and 108.7 kg ± 17.9 of body weight were used. The animals were fed with a total mixed ration during the 91 d of the trial. A phenotypic divergence of DMI for RFI was observed between −0.358 and 0.337 kg/d for HE and LE, respectively. Dry matter intake (DMI) was lower in the HE (2.5 kg DMI/d vs. 3.1 kg DMI/d), as was the number of visits to the feed bin with consumption (59 vs. 71). Feed intake was the best predictor of said divergence. Water intake and number of visits to the feed bin were presented moderate correlations with RFI. The ruminal fermentation variables, blood metabolites, blood hormones (such as the other ingestive behavior variables), and infrared thermography were not able to accurately predict HE or LE animals.
