Amylase addition increases starch ruminal digestion in first-lactation cows fed high and low starch diets

Abstract

The objective of this study was to evaluate the effect of an exogenous amylase preparation on digestion of low- and high-starch diets in dairy cattle. Rumen and total-tract nutrient digestibility were measured in a 4×4 Latin square design with 28-d periods using 4 first-lactation cows cannulated at the rumen and duodenum. Corn silage-based diets had 20 or 30% starch, attained by changing the composition of concentrate, with or without addition of an exogenous amylase preparation. Effects of the enzyme additive were observed on ruminal digestibility but not at the total-tract level. Ruminal digestibility of starch increased from 75% in control to 81% with amylase supplementation. This difference in ruminal starch digestion was compensated postruminally, so that the total-tract digestibility of starch was almost complete and did not differ between treatments. The amylase supplement also increased the true ruminal digestibility of organic matter but did not affect microbial N flow to the duodenum. Amylase supplement reduced the proportion of acetate and butyrate and increased that of propionate, particularly in the high-starch diet, where it tended to increase the concentration of total volatile fatty acids in the rumen. Other effects were a higher amylase activity in the solid-associated microbial community and a tendency for lower numbers of protozoa. In contrast, we observed no changes in intake, production, dry matter and fiber (neutral detergent fiber and acid detergent fiber) digestibility, or ruminal digestion, and no or small changes on selected fibrolytic and amylolytic bacteria and on the microbial community in general. We conclude that the exogenous amylase improved starch digestion in the rumen in first-lactation cows with moderate intake and production levels.

Exogenous Enzymes in Ruminant Nutrition: A Review

“…Xylanolytic enzyme group includes endo-$-1,4-xylanase (1,4-$-D xylan xylanohydrolase, EC 3.2.1.8), which attack the main chain of xylans and $-D-xylosidase (1,4-$-xylan xylanohydrolase, EC 3.2.1.37), which hydrolyze xylooligosaccharides into D-xylose, in addition to a variety of debranching enzymes that is, "-L-arabino-furanosidases, "-glucuronidases and acetyl esterases (Kamble and Jadhav, 2012). Though researches hypothesized that the digestion of starch and protein is not limited within rumen, recent researches conducted with enzyme supplementation with amylolytic activity (Noziere et al, 2014;Klingerman et al, 2009;Gencoglu et al, 2010) and proteolytic activity (Eun and Beauchemin, 2005;Vera et al, 2012) have examined the potential of these enzymes to improve animal performance. Amylase has been divided into three sub classes as ", $ and ( amylase based on the bonding type (Gurung et al, 2013).…”

<b>Performance of beef cattle bulls in feed lots and fed on diets containing enzymatic complex

“…Nozière et al (2014) did not report any positive effects on animal performance with enzyme supplementation higher than doses in current experiment, even though the inclusion of exogenous amylolytic enzymes increased by 8% the degradability of starch in the rumen without any increase in starch digestibility in the entire digestive tract. In an experiment with beef cattle in feedlot with the inclusion of 580 amylolytic units of amylase per kg of dry matter of the diet, J. M. Tricarico et al (2007) registered an increase in voluntary intake of DM and weight gain in the first 28 days in feedlot (14%).…”

Effects of exogenous amylase on the in vitro digestion kinetics of whole‐crop maize silages made from flint or dent grain type at different phenological stages grown in tropical condition

“…This hydrolysis occurs through the cleavage of the α-1.4 and α-1.6 bonds of the starch granules (Tricarico, Johnston, & Dawson, 2008). This effect of amylase is due to the greater hydrolysis of starch (Nozière et al, 2014) providing substrates for the multiplication of other microbial species, mainly fibrolytic micro-organisms (Mccarthy, Engstrom, Azem, & Gressley, 2013), a process defined as cross-feeding among rumen micro-organisms (Russell, 1985) that can improve fibre digestibility by increase in fibre digestion rate as shown in our study. Likewise, Gallo et al (2016) observed that amylase decreased lag time and increased rate and amount of gas production.…”

“…The use of exogenous amylase increases rumen starch degradation (Nozière, Steinberg, Silberberg, & Morgavi, 2014;Vargas-Rodriguez, Engstrom, Azem, & Bradford, 2014). However, responses to exogenous amylase are influenced by the inclusion level and particle size of maize silage (Gallo, Giuberti, Duval, Moschini, & Masoero, 2016) and these studies were made all in temperate conditions using basically dent-type maize hybrids.…”