Effects of rumen-protected methionine on plasma amino acid concentrations during a period of weight loss for late gestating beef heifers

Abstract

This study determined changes in plasma amino acid concentration in late-gestating (beginning 58 ± 1.02 days prior to calving), primiparous, winter-grazing range heifers receiving wheat middling-based supplement without (CON) or with rumen-protected methionine (MET) to provide 15 g DL-MET each day. Plasma was collected on days -2 and 0 (start of MET supplementation just prior to individually receiving supplement at 0700 hours). Plasma was sampled again on days 40, 42 and 44 prior to supplementation at 0700 and 1100 hours (4 h after receiving daily supplement). Data were analyzed with cow as the experimental unit. Continuous variables were analyzed by the main effects of treatment, date, or time and their interaction when appropriate. Comparable BW (P = 0.32) and BCS (P = 0.83) over the 44-day metabolism trial were found between both CON- and MET-fed heifers. MET-supplemented heifers had greater (P < 0.01) plasma concentrations of methionine indicating that the rumen-protection technology successfully delivered methionine to the small intestine. Supplementation with rumen-protected DL-MET caused a significant supplement × date interaction for glutamine (P = 0.03), glycine (P = 0.02), methionine (P < 0.01), and serine (P = 0.05). In addition, trends for supplement × date interactions were detected for leucine (P = 0.07), threonine (P = 0.09), valine (P = 0.08), total amino acids (TAA; P = 0.08), non essential amino acids (NEAA; P = 0.08), branched chain amino acids (BCAA; P = 0.08), and glucogenic amino acids (GLUCO; P = 0.08). These results suggest that the BCAA (leucine and valine) were utilized more efficiently with MET supplemented heifers compared to CON supplemented heifers. Plasma AA concentrations for glutamic acid (P < 0.01), histidine (P = 0.01), tyrosine (P < 0.01), and EAA (P < 0.01), all decreased throughout the study. These results further confirm methionine is a limiting amino acid in forage fed late-gestating heifers and further suggests the limitation when grazing dormant range forages as shown by improved utilization of other plasma amino acids when supplemental methionine was provided.

Regulation of Nutritional Metabolism in Transition Dairy Cows: Energy Homeostasis and Health in Response to Post-Ruminal Choline and Methionine

“…Thus, the effects of supplementation of these nutrients on metabolism under NEB conditions were examined. In this experiment, the treated transition cows fully consumed 60.0 g/d ReaShure ® and 17.7 g/d Mepron ® ; these doses are within the suggested supplementation range [ 25 , 34 ].…”

“…RPC was supplied as 60.0 g/d ReaShure ® (choline chloride content 25.0%, rumen bypass rate 85.0%, Balchem Corp., New Hampton, USA) [ 24 ]. RPM was provided as 17.7 g/d Mepron ® (DL-methionine content 85.0%, rumen bypass rate 80.0%, Evonik Industries, Mobile, Alabama, USA) [ 25 ].…”

BEEF SPECIES SYMPOSIUM: An assessment of the 1996 Beef NRC: Metabolizable protein supply and demand and effectiveness of model performance prediction of beef females within extensive grazing systems1,2,3

“…Both primary sources of dietary protein contribute to the MP supply delivered to the host animal, as will be discussed in subsequent paragraphs. Nutrient partitioning can be influenced by the type of protein supplied (Hunter and Magner, 1988;Miner and Petersen, 1989;Miner et al, 1990), the use of rumen-protected AA (Richardson and Hatfield, 1978;Waterman et al, 2007bWaterman et al, , 2012, or a supplement that supplies specific nutrients that target both an energy and protein deficiency in the host animal (Waterman et al, 2006;Mulliniks et al, 2011Mulliniks et al, , 2013.…”

“…The concept and relevance of specific AA supplementation as rumenprotected products have been discussed for decades (Chalupa, 1975;Clark, 1975). Progress with rumen protection technologies has led to protected methionine and lysine in markets, has considerable traction in the dairy industry (Sniffen et al, 2013a,b), and has become an active area of research for beef cattle and sheep (Hess et al, 1998;Klemesrud et al, 2000;Archibeque et al, 2002;Waterman et al, 2007bWaterman et al, , 2012Meyer et al, 2011;Peine et al, 2013). The role of rumen-protected AA will be discussed in more detail in subsequent sections.…”

Humoral immune response in beef heifers supplemented with mineral salt with or without the addition of rumen-protected methionine

“…With the improvement in the formulation of ruminant diets, the concept of metabolizable protein was consolidated as an important basis in the evaluations. Due to the essentiality of certain amino acids such as methionine for this species associated with its limitation in forages with low protein levels, strategies that increase its availability by protecting against ruminal degradation shows promising results (WATERMAN et al, 2012).…”