03037naa a2200373 a 450000100080000000500110000800800410001902400550006010000260011524501380014126000090027952019520028865000210224065000240226165000140228565000090229965000110230865000180231965000220233765000240235965000110238365300130239470000220240770000110242970000220244070000180246270000190248070000190249970000200251870000230253870000240256170000230258577300550260821463772022-09-13       2022    bl uuuu     u00u1 u    #d7 ahttps://doi.org/10.1590/1984-3143-AR2021-00882DOI1 aCARVALHEIRA, L. de R.  aDiet crude protein reduction on follicular fluid and cumulus-oocyte complexes of mid-lactating Girolando cows.h[electronic resource]  c2022  aThis 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 rumenundegradable 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&lt0.001). 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&lt0.09), and also a linear increase for the number (P=0.0397) and proportion (P&lt0.09) 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.  aAnimal nutrition  aAnimal reproduction  aApoptosis  aUrea  aBovino  aGado Leiteiro  aNutrição Animal  aReprodução Animal  aUréia  aApoptose1 aSANTOS, G. B. dos1 aJASMIM1 aGUIMARÃES, C. R.1 aCAMPOS, M. M.1 aMACHADO, F. S.1 aPEDROSO, A. M.1 aSILVA, T. E. da1 aNOGUEIRA, L. A. G.1 aRODRIGUES, A. L. R.1 aCARVALHO, B. C. de  tAnimal Reproductiongv. 19, n. 3, e20210088, 2022.