Effect of Prepartum Dietary Protein Level on Performance of Primigravid and Multiparous Holstein Dairy Cows

Abstract

This study compared the effects of two levels of crude protein (CP) fed during late gestation on the performance, blood metabolites, and ovarian activity of Holstein cows. One-hundred and six cows (42 primigravid and 64 multiparous) 32 d before calving were divided into two groups and fed diets containing moderate (12.7% CP, 36% rumen undegradable protein, (RUP) or high (14.7% CP, 40% RUP) protein. Higher prepartum CP diet increased milk production during the first 120 d in milk (DIM), but most of that effect was detected for the primigravid cows. Primigravid cows fed the prepartum diet higher in protein produced 2.0 kg/d more milk and 3.1 kg/d more 3.5% fat-corrected milk (FCM) during early lactation. Yields of milk fat and protein in early lactation were also increased by the high prepartum CP diet fed to primigravid cows. During the complete lactation, the response to prepartum dietary protein differed between primigravid and multiparous cows. Yields of milk, 3.5% FCM, and milk fat and protein were not affected by the prepartum diet for primigravid cows, but decreased for multiparous cows fed the high protein diet. However, primigravid cows fed the high prepartum protein diet had a higher 305-d mature equivalent milk yield. Colostrum composition, blood metabolites, ovarian activity, and disease incidence were not influenced by prepartum protein. Data from this study suggest that the current prepartum protein recommendation seems to be adequate for multiparous cows, but late-gestation primigravid cows might benefit from diets with a CP content above 12.7%.

Factors affecting dry matter intake prepartum in relationship to etiology of peripartum lipid-related metabolic disorders: A review

“…Using a large database, Hayirli et al (2002) showed that there was no difference in DMI of dairy cattle fed diets containing 13.3 ± 0.6 (n = 380), 15.2 ± 0.8 (n = 156), and 17.7 ± 1.5 (n = 164) % CP. A lack of beneficial prepartum and postpartum responses in DMI to increased level of dietary CP during the prefresh transition period (Hayirli 1997;Hayirli et al 2002) may suggests the previous NRC's CP recommendation (NRC 1989) satisfactorily meets the protein needs of multiparous cows, approaching parturition (NRC 2001;Santos et al 2001). In a recent study, Philips et al (2003) also reported that increasing CP level from 11 to 14% with supplemental methionine hydroxy analog (20 g d -1 ) during the prefresh transition period did not affect the peripartum DMI and postpartum milk production.…”

Effects of increasing days of exposure to prepartum transition diets on milk production and milk composition in dairy cows

“…The potential, however, to increase production, improve health and improve reproduction has made nutritional manipulation of the peri‐parturient cow a focus for research. Increased milk production and improved energy or nitrogen balance have resulted from manipulating the energy density, 1,2 protein density, 3–5 amino acid profile 6,7 and dietary cation–anion difference (DCAD) 8,9 of prepartum diets. Although there has been considerable research on the effects of manipulating various components of the prepartum transition diet, few studies have integrated these manipulations to produce an ‘optimal’ prepartum transition diet or studied the effect of the duration of feeding prepartum transition diets on performance.…”

Concentrações de nitrogênio na dieta, no sangue e no leite de vacas lactantes no período pós-parto

“…Este resultado confirma aqueles registrados por Howard et al (1987) e Santos et al (2001), que observaram que o escore de condição corporal (ECC) médio nos períodos pré e pós-parto não foi influenciado pelos níveis de proteína da dieta e sugeriram que o aumento da densidade protéica no pré-parto não tem impacto na perda de reservas corporais durante as últimas quatro semanas de gestação e nas primeiras 21 semanas pós-parto.…”

“…Também neste estudo, as produções de leite, obtidas em quantidades cada vez menores de P100 para P133 e P166, poderiam enquadrar-se em um padrão de rendimentos decrescentes, no qual incrementos equivalentes em PB (equivalente protéico) correspondem a aumentos cada vez menores na produção de leite, conforme descrito por Chalupa (1984). Outros autores, como Santos et al (2001) e Baker et al (1995, contrariando esse dados, não encontraram alterações nas produções leiteiras, ao empregarem elevados níveis de proteína na dieta.…”

“…Excessos de PB na dieta foram relacionados a menores produções de leite, a altos níveis de NUL e a maior custo de alimentação (Arias & Alonso, 1997). Finalmente, outros autores, como Santos et al (2001) e Baker et al (1995), não encontraram alterações nas produções de leite de vacas alimentadas com maiores quantidades de PB, durante o pós-parto. Ressalta-se que quantidades reduzidas de proteína, 20% abaixo do recomendado pelo NRC (1989), são responsáveis por menores concentrações de NUS em vacas secas nos 60 dias pré-parto (Chew et al, 1984).…”