Diet crude protein reduction on follicular fluid and cumulus-oocyte complexes of mid-lactating Girolando cows
Carvalheira, Luciano de Rezende; Santos, Gustavo Bervian dos; Jasmin, Jasmin; Guimarães, Clóvis Ribeiro; Campos, Mariana Magalhães; Machado, Fernanda Samarini; Pedroso, Alexandre Mendonça; Silva, Tadeu Eder da; Nogueira, Luiz Altamiro Garcia; Rodrigues, André Luís Rios; Carvalho, Bruno Campos de.
Anim. Reprod. (Online);
19(3): e20210088, set. 2022. tab, ilus, graf
Artigo
em Inglês
| VETINDEX
| ID: biblio-1393227
Resumo
This study evaluated the effect of crude protein (CP) reduction in four diets (156, 139, 132, and 127 g Kg-1 DM) maintaining constant metabolizable protein (188 g/day) on the follicular fluid and cumulus-oocyte complexes of mid-lactating Girolando cows. Twenty-two Girolando cows with average of 21.55 ±3.19 L daily milk yield, 105.30 ±22.62 days in lactation and 3.22 ±0.03 body condition score were selected. To reduce CP in diets and maintain constant metabolizable protein, urea and soybean meal were gradually replaced by lignosulfonate-treated soybean meal (SoyPass®, Cargill), resulting in an increase in rumen-undegradable protein and a reduction in rumen degradable protein. A linear and quadratic reduction was observed in the plasma and follicular fluid urea nitrogen concentration following CP reduction, with the most intense reduction occurring in the 127 g Kg-1 DM group (p<0.001). As CP reduced, there was a tendency for a linear increase in the follicular growth rate (P=0.0696), on the number and proportion of viable oocytes (P<0.09), and also a linear increase for the number (P=0.0397) and proportion (P<0.09) of grade I viable oocytes. Plus, there was a linear effect for the number of cumulus oophorus cells. Cows fed with the lowest amount of CP had cumulus-oocyte complexes with higher numbers of cumulus oophorus cells (P=0.0238). Also, the reduction of diet crude protein was followed by a decrease in the probability of oocytes' DNA degradation. In conclusion, the reduction of CP in the diet of mid-lactating Girolando cows, reduces urea nitrogen concentration in both blood plasma and follicular fluid, and, as a consequence, increases the viability of oocytes and the number of cumulus oophorus cells while reducing oocytes' DNA degradation of follicular included cumulus-oocyte complex. The reduction on dietary CP may improve in vivo oocytes' embryo development impacting fertility of lactating dairy cows.(AU)
Biblioteca responsável:
BR68.1
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