Comparative Effects of Supplemental DL-2-hydroxy-4-[methylthio] Butanoic Acid and DL-methionine in Diet on Egg Production and Quality in Laying Hens

Abstract

This study was conducted to compare the effects of DL-2-hydroxy-4-[methylthio] butanoic acid (HMB) and DLmethionine (DLM) on egg production performance and egg quality of laying hens. Two hundred and eighty-eight commercial laying hens were assigned to 3 dietary treatment groups and fed the experimental diets from 34 to 46 weeks of age. The bioefficacy of HMB relative to DL-methionine (DLM) was set at 88% (weight/weight), therefore 0.115% of HMB and 0.101% of DLM were added to a basal diet. DLM and HMB supplementation increased body weight, feed intake, hen-day egg production, egg weight, FCR and egg mass (P＜0.01). These supplementations also increased yolk and albumen weight (g/egg) (P＜0.01), while DLM slightly decreased albumen weight (% of egg). Consequently, Haugh unit was poor by DLM supplementation but did not by HMB supplementation (P＜0.05). DLM supplementation significantly increased fat content in egg (g/egg and % of egg), though level of estradiol in blood was elevated by HMB supplementation. In conclusion, HMB supplementation (as 88% bioefficacy of DLM) can be used as an effective methionine source. However, mechanism of protein and fat synthesis and/or degradation of laying hens may be differed when different form of methionine is supplied.

Effects of dietary methionine on productivity, reproductive performance, antioxidant capacity, ovalbumin and antioxidant-related gene expression in laying duck breeders

“…In Shaoxing laying ducks, the Haugh unit and yolk colour were not affected, but the albumen height and eggshell thickness increased after the Met levels changed from 0·26 to 0·54 % ( 6 ) . Supplementing the diets of laying hens with various formulations of Met had inconsistent effects on the egg quality traits that were affected in the present study with Longyan breeders ( 3 , 20 , 32 ) . In the current study, increasing dietary Met led to linear increases in the albumen weight, together explaining the increase in egg weight and likely accounting for the weight of hatchlings ( 33 ) .…”

“…A similar improvement in egg production was obtained after doubling the amount of Met in the basal diets (0·26 %) of Tsaiya laying ducks for 4 weeks ( 31 ) . Feeding laying hens diets containing 0·26 % Met for 12 weeks starting from 34 weeks of age impaired egg production, egg weight, egg mass and FCR, but adding 0·10 % Met normalised these effects ( 3 ) . In White Leghorn laying hens, Panda et al ( 32 ) showed that egg production, egg weight, egg mass and FCR were not affected by increasing the Met level from 0·30 to 0·42 % in different feed sources for 16 weeks during the peak laying period.…”

“…2·5 Met/kg) might affect the activities of antioxidant enzymes and their mRNA expression levels in duck breeders and their offspring by modulating the expression of nuclear factor erythroid 2 like 2 ( Nrf2 ), but this has not been investigated previously. Moreover, previous reports have shown that dietary Met levels increases the egg weight and albumen secretion in different strains of laying ducks and laying hens, which was reflected in egg weight ( 3 , 6 , 7 ) , but the relationship between them was little referred. Thus, it might be possible that dietary Met can induce the same effect in duck breeders as laying ducks, which may lead to an increase in the weight of hatchings, by altering gene expression of ovalbumin (OVAL , the dominant protein in albumen) in duck breeders.…”

“…In poultry, Met improves the productivity, reproductive performance, egg quality, antioxidant defence system and humoral and cellular immune responses, and attenuates the adverse impacts of non-optimal temperature (cold or heat stress) ( 5 , 7 , 18 , 19 ) . Thus, the effects of Met on commercial and local strains of broiler breeders, laying hens, quails, turkeys, meat-type and egg-type ducks can be positive, but variable ( 3 , 6 , 7 , 18 , 20 , 21 ) . Further, few studies have reported the effect of dietary Met levels in laying duck breeders.…”

Dietary methionine source and level affect hepatic sulfur amino acid metabolism of broiler breeder hens

“…Methionine is often considered to be the first limiting amino acid for laying hens and supplementation of methionine is important to optimize the performance and health of layers. Considerable evidence in the literature supports the fact that 2hydroxy-4-(methylthio) butanoic acid (HMTBA), and 2-hydroxy-4-(methylthio) butanoic acid-calcium salts (HMTBA-Ca) can replace DL-methionine (DLM) as an effective methionine source in the diet of broilers (Sauer et al 2008), pigs (Kim et al 2006) and laying hens (Liu et al 2005;Bunchasak et al 2012).…”