Effect of Protein Restriction During Mid-to Late Gestation of Beef Cows on Female Offspring Fertility, Lactation Performance and Calves Development

Cow calf operation in Argentina are managed under extensive grazing condition and the quality of forages is often poor during second half of gestation. Protein restriction in bovine gestation affects production traits in progeny. The present work investigated the effects of two levels of crude protein (CP) provided to mature dams during late gestation on subsequent heifer’s growth postweaning, reproductive performance, milk production and grand offspring evolution. At 121 d prepartum, 68 multiparous Angus cows were randomly assigned to low protein (LP, 6% CP) or high protein (HP, 12% CP) at 12 pens per treatment group. Following calving, all cow/calf pairs were housed together until weaning, then female progeny were removed and maintained on pasture as a single group. At puberty (P = 0.01) and pregnancy determination (P = 0.05) the HP heifers were heavier than LP heifers. The LM area was greater at 20 mo of age in HP compared to LP heifers (P = 0.01) and the HP heifers had greater 12th rib fat thickness at 30 and 35 mo of age (P = 0.02). Serum IGF-1 concentration was greater in HP heifers compared to LP heifers (P = 0.05). No dam nutrition effects were found on offspring age at puberty (P = 0.98), final pregnancy rate (P = 0.28) or milk yield (P = 0.76) but heifers born to LP dams had greater milk protein percentage (P = 0.04) and tended to produce increased milk fat percentage (P = 0.08) compared with HP heifers. The LP grand offspring grew faster from birth until weaning compared with HP grand offspring (P < 0.01) with reduced insulin concentrations (P = 0.03) and tended to have increased glucose concentrations than HP calves (P = 0.09). Protein supplementation during late gestation does not affect reproductive performance of the offspring heifers but did impact their BW evolution, milk quality and grand offspring performance. Implications: The use of diet with low amount of protein which the female fetus is exposed in utero can affect her subsequent development and ability to nourish subsequent generations.EEA Cuenca del SaladoFil: Lopez Valiente, Sebastian. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cuenca del Salado; ArgentinaFil: Maresca, Sebastian. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cuenca del Salado; ArgentinaFil: Rodriguez, Alejandro Martin. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cuenca del Salado; ArgentinaFil: Long, Nathan M. Clemson University. Department of Animal and Veterinary Sciences; Estados UnidosFil: Quintans, Graciela I. Instituto Nacional de Investigación Agropecuaria (INIA); UruguayFil: Palladino, Rafael Alejandro. Universidad Nacional de Lomas de Zamora. Facultad de Ciencias Agrarias; ArgentinaFil: Palladino, Rafael Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Effect of protein restriction of bovine dams during late gestation on offspring postnatal growth, glucose-insulin metabolism and IGF-1 concentration

The objective of this study was determine whether the amount of protein provided to cows during late gestation would affect postnatal growth and lead to changes on glucose, insulin and insulin-like growth factor concentrations. At 134 d prepartum, 68 multiparous Angus cows were blocked by BW and expected calving date and randomly assigned to low protein level (LP, 6% CP) or high protein level (HP, 12% CP) and were allotted in 12 pens per treatment. At calving, cows were managed together on improved pastures until weaning. Calves were weighed and body measurements were recorded at birth. Blood samples were taken at birth and each 30 d until weaning at 180 d of age. Body weight at birth on HP progeny tended to be great than LP progeny (P = 0.06). At birth, calves from LP dams had greater head circumference (P 〈 0.01), heart girth (P = 0.01) and cannon bone circumference (P = 0.02). However, head circumference /birth BW ratio (P = 0.04), heart girth /birth BW ratio (P = 0.01), body length /birth BW ratio (P = 0.05) and height /birth BW ratio (P = 0.01) was greater on LP calves. Body mass index was greater in HP calves (P = 0.04). No differences were found on BW of calves at weaning, adjusted 205d BW and ADG during lactation (P 〉 0.10). Glucose concentrations were greater on LP calves than HP calves from birth to weaning (81.0 ± 1.5 vs. 76.4 ± 1.2 mg/dl; P 〈 0.001) without any change in insulin concentrations during preweaning growth (LP = 1.61 ± 0.04 ng/ml; HP = 1.61 ± 0.04 ng/ml; P 〉 0.10). Insulin-like growth factor concentrations was less on LP calves at birth (P 〈 0.05) and similar to HP calves during postnatal growth (P 〉 0.10). These data demonstrate that low protein during late gestation in bovine dams may affect fetal growth with proportional increasing of head circumference and low body mass index. Level of protein compromised glucose regulation in early life and affected the IGF-I concentration of newborn calves.EEA Cuenca del SaladoFil: Maresca, Sebastian. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cuenca del Salado; ArgentinaFil: Lopez Valiente, Sebastian. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cuenca del Salado; ArgentinaFil: Rodriguez, Alejandro Martin. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cuenca del Salado; ArgentinaFil: Long, Nathan M. Clemson University. Department of Animal and Veterinary Sciences; Estados UnidosFil: Pavan, Enrique. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Quintans, Graciela I. Instituto Nacional de Investigación Agropecuaria (INIA); Urugua

Late-gestation protein restriction negatively impacts muscle growth and glucose regulation in steer progeny

The objective of this study was to determine whether the amount of protein provided to cows during late gestation would affect postnatal growth and lead to changes in glucose and insulin concentrations. At 129 d of gestation, 10 mature multiparous Angus cows were stratified by body weight (BW) and body condition score (BCS) and allotted to either low protein level (LP, 6% crude protein [CP]) or high protein level (HP, 12% CP) groups. After calving, cows were managed together on improved pastures, which provided forage in excess of requirements until weaning. Male calves were maintained as a group after weaning on native range until 23 mo of age when individual steers were placed in single pens and fed a finishing diet for 84 d. The 12th rib fat thickness and longissimus muscle area were measured during finishing phase by ultrasound. Twenty days before the end of the finishing phase, steers were subjected to an intravenous glucose tolerance test. Steers were harvested and carcass characteristics collected. Cows' BW and BCS were similar at the initiation of treatment. During treatment HP dams gained 21 kg, whereas LP dams lost 7 kg (P = 0.04). Protein nutrition during late gestation did not influence calf birth weight, BW at weaning, adjusted 205 d BW, or average daily gain during lactation (P > 0.10). Longissimus muscle area measure by ultrasound was greater (P = 0.02) in HP steers at the beginning and end of finishing phase. Fat thickness of the 12th rib was not different (P > 0.10) between treatments. Glucose concentration after intravenous administration decreased (P = 0.002) in LP compared with HP steers. Peak of serum insulin concentration was greater (P = 0.04) and serum insulin concentration tended to decrease (P = 0.08) more rapidly in LP compared with HP steers after glucose infusion. At harvest, hot carcass weight was similar between treatments, but dressing percentage was increased (P = 0.05) in HP compared with LP steers. These data demonstrate that a lower protein nutrition level of dams during late gestation affect carcass characteristics and alter glucose regulation enhancing insulin secretion in steer progeny.EEA Cuenca del SaladoFil: Maresca, Sebastian. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cuenca del Salado; ArgentinaFil: Lopez Valiente, Sebastian. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cuenca del Salado; ArgentinaFil: Rodriguez, Alejandro Martin. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cuenca del Salado; ArgentinaFil: Pavan, Enrique. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Quintans, Graciela I. Instituto Nacional de Investigación Agropecuaria (INIA); UruguayFil: Long, Nathan M. Clemson University. Department of Animal and Veterinary Sciences; Estados Unido

The influence of protein restriction during mid- to late gestation on beef offspring growth, carcass characteristic and meat quality

The objective of this study was to determine whether crude protein intake during the last three months of gestation affects growth performance, carcass characteristics and meat quality of steer progeny. At 134 ± 14 d of gestation, 68 multiparous Angus cows were blocked by BW and expected calving date and randomly assigned to diets that contained either low or high dietary crude protein concentrations and were allotted in 12 pens per treatment. After calving, cows were managed together on improved pastures during lactation. After weaning at 219 ± 13 d of age, steers calves were stockered on natural pastures until 687 ± 13 d of age then placed into a feedlot for 83d before slaughter. Maternal dietary protein concentration had no influence on offspring body weight and growth rate during rearing or finishing phases (P > .10). Rib fat thickness of steers was not affected (P = .38) by maternal nutrition treatments, however, LM area was greater in HP steers than LP steers at entrance into the feedlot (P = .01) and end of finishing phase (P = .04). Hot carcass weight was similar between treatments (P = .69), however dressing percentage was increased in HP relative to LP steers (P = .01). Tenderness of Longissimus muscle was increased in HP compared to LP steers after 3 and 14d (P < .001) of aging. No treatment differences in troponin-t degradation (P = .77) and collagen content (P = .58) were observed. Muscle fiber diameter was similar in LP and HP steers (P = .20), suggesting that increase of LM area in HP steers could be due to muscle hyperplasia. These data indicated that level of protein during mid to late gestation does not affect offspring growth but has impacts on carcass composition and meat quality of steer progeny.EEA Cuenca del SaladoFil: Maresca, Sebastian. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cuenca del Salado; ArgentinaFil: Lopez Valiente, Sebastian. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cuenca del Salado; ArgentinaFil: Rodriguez, Alejandro Martin. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cuenca del Salado; ArgentinaFil: Testa, Maria Laura. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Long, Nathan M. Clemson University. Department of Animal and Veterinary Sciences; Estados UnidosFil: Quintans, Graciela I. Instituto Nacional de Investigación Agropecuaria (INIA); UruguayFil: Pavan, Enrique. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina. Clemson University. Department of Animal and Veterinary Science; Estados Unido

Effect of protein restriction of Angus cows during late gestation: Subsequent reproductive performance and milk yield

The effect of level of CP fed during late gestation on reproductive performance and milk production was studied in multiparous cows. Sixty-eight pregnant Angus cows were used. At 121 d prepartum, cows were blocked by BW (409 ± 57 kg) and expected calving date, randomly assigned to a low-protein (LP = 6% CP) or high-protein diet (HP = 12% CP), and allocated to 12 pens per treatment. After parturition, all cows were managed in a single group until weaning. Body weight and BCS were determined at the start of the experiment, at calving, and at weaning. Nonesterified fatty acids, insulin, IGF-1, and glucose were determined every 24 d prepartum and nonesterified fatty acids and glucose every 38 d postpartum. Progesterone was quantified weekly to indicate luteal activity and estimate interval to first estrus. Milk production was measured until weaning. The HP cows had greater BW gain during the prepartum period (P < 0.01) and tended to gain more BCS (P = 0.06) than LP cows. The prepartum diet did not affect gestation length (P = 0.44) or interval from calving to the onset of luteal activity (P = 0.35). Pregnancy rates, milk quality, and production were not influenced by dietary treatments. Cows in the HP treatment had greater prepartum serum urea concentrations than LP treatment (P < 0.05). In conclusion, protein level prepartum in multiparous beef cows affected the BW change at calving, without consequences on reproductive performance and milk quality and yield.EEA Cuenca del SaladoFil: Lopez Valiente, Sebastian. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cuenca del Salado; ArgentinaFil: Maresca, Sebastian. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cuenca del Salado; ArgentinaFil: Rodriguez, Alejandro Martin. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Cuenca del Salado; ArgentinaFil: Palladino, Rafael Alejandro. Universidad de Buenos Aires. Facultad de Agronomía; Argentina. Universidad Nacional de Lomas de Zamora. Facultad de Ciencias Agrarias; ArgentinaFil: Lacau Mengido, Isabel M.. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental. Laboratorio de Regulación Hipofisaria; ArgentinaFil: Long, Nathan M. Clemson University. Department of Animal and Veterinary Sciences; Estados UnidosFil: Quintans, Graciela I. Instituto Nacional de Investigación Agropecuaria (INIA); Urugua