Does the addition of choline and/or betaine to diets reduce the methionine requirements of laying quails? Assessment of performance and egg antioxidant capacity

The purpose of the present study was to assess the performance, quality of eggs internally and externally, and antioxidant capacity of yolks in laying quails with the administration of choline and betaine to diets containing reduced methionine levels. A total of 150 Japanese laying quails (Coturnix coturnix japonica) at the 10-wk age were randomly assigned to 6 experimental groups, each consisting of 5 replicates and 5 birds for 10 wk. The treatment diets were designed by adding the following substances: 0.45% methionine (C), 0.30% methionine (LM), 0.30% methionine + 0.15% choline (LMC), 0.30% methionine + 0.20% betaine (LMB), 0.30% methionine + 0.075% choline + 0.10% betaine (LMCB1), 0.30% methionine + 0.15% choline + 0.20% betaine (LMCB2). The treatments did not affect performance, egg production, or egg internal quality (P > 0.05). No significant effect was determined on the damaged egg rate (P > 0.05), but the egg-breaking strength, eggshell thickness, and eggshell relative weight decreased in the LMCB2 group (P < 0.05). Regarding lipid peroxidation, treatments did not affect the yolk 2,2 diphenyl-1-picrylhydrazyl value (P > 0.05), although the lowest thiobarbituric acid reactive substances value was observed in the LMB compared to the control group (P < 0.05). It may be summarized that methionine can be decreased to levels of 0.30% for laying quail diets with no negative effect on performance, egg production, or egg internal quality, whereas the combination of methionine (0.30%) and betaine (0.2%) could improve antioxidant stability of eggs over the 10-wk experimental period. These findings provide useful information to the traditional recommendations on the requirements of laying quail. However, further studies are needed to test whether these effects persist throughout extended study periods.

Linking key husbandry factors to the intrinsic quality of broiler meat

Broiler farming is the fastest-growing animal production sector and broiler meat is the second most-consumed meat in the world. The intensification of broiler production often has a negative impact on the meat quality and carcass characteristics. Consumers, however, expect a quality product from animals reared extensively on farms providing good animal welfare, often intuitively associated with extensive farming practices. Therefore, this literature review investigates how the critical factors contributing to the degree of extensiveness of broiler production affect the quality of meat. We used the data from scientific articles published in the years 2012-2021 to analyze the effect of diet (n = 409), genetics (n = 86), enrichment (n = 25), and stocking density (n = 20) on meat quality and carcass characteristics. Minerals and microelements supplementation in the diet improved all the meat quality aspects: sensory, physical, and chemical in most studies. Minerals and enzymes in the diet had beneficial effects on carcass characteristics, unlike feed restriction and ingredient substitutions. The impact of outdoor access on meat quality and carcass characteristics was most frequently examined, in contrast to the use of perches or effects of litter quality. Overall, enrichment did not affect the meat's sensory or physical parameters, but outdoor access improved its lipid composition. Lower stocking density deteriorated intramuscular fat content, decreased tenderness and juiciness, yet lowered cooking and drip loss, and increased carcass and breast muscle yields. When it comes to genetics, in general, slow growing broiler strains have better meat quality parameters, especially regarding yellowness (b*), redness (a*), cooking and drip loss. Our review shows that the factors which contribute to extensiveness of broiler production systems and birds' welfare also affect meat quality and the carcass characteristics.

Effects of Feeding Varying Levels of DL-Methionine on Live Performance and Yield of Broiler Chickens

Simple Summary

The use of DL-methionine (MET) in poultry diet formulation is vital for poultry growth because poultry do not synthesize sufficient amounts of MET needed for proper growth and performance, and currently there are insufficient natural sources of MET to fulfill the dietary needs of broiler chickens. However, the use of MET is restricted in the United States in organic poultry diets. Therefore, the objective of this study was to examine the effect of feeding different levels of dietary MET on organic broiler live performance and yield of a modern commercial broiler strain. This study gives us insight into how broiler growth and yield is affected when the allowable levels of methionine for organic broilers is further reduced, or zero methionine is used.

Abstract

This study was designed to evaluate the effects of dietary supplemental DL-methionine (MET) on live performance and meat yield for broilers raised to a common weight. A total of 1552 one-day old Ross 708, sexed broilers were randomly distributed to 32 pens resulting in eight treatments (TRT) of four replicates with 44 male or 53 female/pen. A randomized complete block with a 2 × 4 (sex × 4 MET levels 0, 0.5, 1, and 2 g/kg) factorial arrangement of TRT was used. A common weight of 2400 g was approached by day 46 (1 and 2 g MET/kg feed) and day 48 (0 and 0.5 g MET/kg feed). Supplementation of MET at 1, and 2 g/kg had a lower (p < 0.01) feed conversion ratio (FCR) at day 46/48 than broilers fed 0.5 g MET/kg. Broilers without supplemental MET had the worst (p < 0.01) feed conversion and average daily gain (ADG) at day 46/48. Birds fed 0 g MET/kg of feed had lower (p < 0.05) whole eviscerated carcass without giblets (WOG), yield than birds fed 2 g MET/kg of feed. Additionally, birds fed 0 g MET/kg of feed had lower (p < 0.05) breast fillet and tender percent yields than birds fed supplemental MET. Elimination of MET from organic broiler diets resulted in reduced ADG, breast fillet yield and feed efficiency of meat yield of broilers raised to day 46/48. Reduction in MET supplementation below current levels reduced the efficiency of meat production of organic broilers raised to day 46/48.

Prebiotics and alternative poultry production

Alternative poultry production systems continue to expand as markets for organic and naturally produced poultry meat and egg products increase. However, these production systems represent challenges associated with variable environmental conditions and exposure to foodborne pathogens. Consequently, there is a need to introduce feed additives that can support bird health and performance. There are several candidate feed additives with potential applications in alternative poultry production systems. Prebiotic compounds selectively stimulate the growth of beneficial gastrointestinal microorganisms leading to improved health of the host and limiting the establishment of foodborne pathogens. The shift in the gastrointestinal microbiota and modulation of fermentation can inhibit the establishment of foodborne pathogens such as Campylobacter and Salmonella. Both current and potential applications of prebiotics in alternative poultry production systems will be discussed in this review. Different sources and types of prebiotics that could be developed for alternative poultry production will also be explored.

An overview of health challenges in alternative poultry production systems

Due to consumer demand and changing welfare standards on health, ecology, equity, and safety concepts, poultry production has changed markedly over the past 20 y. One of the greatest changes to poultry production standards is now offering poultry limited access to the outdoors in alternative and organic poultry production operations. Although operations allowing access to the outdoors are still only a small portion of commercial poultry production, it may impact the gastrointestinal (GIT) health of the bird in different ways than birds raised under conventional management systems. The present review describes current research results in alternative systems by identifying how different poultry production operations (diet, environmental disruptive factors, diseases) impact the ecology and health of the GIT. Various research efforts will be discussed that illustrate the nutritional value of free-range forages and how forages could be beneficial to animal health and production of both meat and eggs. The review also highlights the need for potential interventions to limit diseases without using antibiotics. These alternatives could enhance both economics and sustainability in organic and free-range poultry production.

Nutrition, feeding and laying hen welfare

The relationship between nutrition and welfare is usually considered to be a direct result of supplying the hen with adequate quantities of feed and water. This simple notion of freedom from hunger and thirst belies the fact that nutrients play a pivotal role in the body’s response to challenges whether they relate to ambient temperature, gastrointestinal health, pathogen exposure, metabolic disorders, or social and mental stress. In all instances, maintaining homeostasis and allowing for physiologic response is dependent on an adequate and balanced nutrient supply. It is accepted that most laying hens are fed a complete diet, formulated commercially to provide the required nutrients for optimal health, egg production and welfare. In other words, the laying hen, irrespective of her housing, does not experience hunger or thirst. However, despite adequate nutrient and water supply, certain senarios can significantly affect and alter the nutrient requirements of the hen. Furthermore, the chemical composition and also the physical form of feed can significantly contribute to prevent or treat welfare and health conditions and is, therefore, a highly relevant tool to ensure and maintain an adequate welfare status. Therefore, this review takes a broader perspective of nutritional welfare and considers the nutrition of hens managed in different production systems in relation to nutritional physiology, gut microbiota, stress, metabolic disorders and feeding management.

Biorefined grass-clover protein composition and effect on organic broiler performance and meat fatty acid profile

Protein extracted from green biomass can be a sustainable and valuable feed component for organic poultry production. Earlier studies in rats have shown high digestibility of laboratory-scale extracted protein. The aim of this study was to test the effect of upscaling the biorefining process on composition of protein extracted from organic grass-clover and on performance of organic broilers when including grass-clover in the feed. Crude protein content of the extracted grass-clover protein was 36.2% of dry matter (DM) with a higher methionine content, but lower lysine and total sulphur-containing amino acids than that in soybean. Acid-insoluble residue constituted a major fraction of the dietary fibre content, and a large proportion of total CP was bound in this fraction. Alpha-linolenic acid was the dominating fatty acid in the extracted grass-clover protein. One-day-old organic Colour Yield broiler chicks were included in a dose-response trial with grass-clover protein constituting 0%, 8%, 16% or 24% of the feed from day 12 and until slaughter at day 57. Increasing levels of grass-clover protein extract reduced feed intake, growth and slaughter weight; however, at 8% inclusion feed intake and performance were not affected. The fatty acid composition in broiler breast meat reflected the composition of grass-clover protein extract; thus, the increasing dietary addition increased meat alpha-linolenic acid content. A lowered tocopherol content in meat from broilers fed increasing grass-clover protein demonstrated the need for increased amounts of antioxidants due to the high content of unsaturated fat. In conclusion, the study shows that broilers can grow on grass-clover protein from an upscaled biorefining process, but highlights the importance of further optimisation with focus on increased protein content and on avoiding formation of insoluble protein complexes, as these most likely reduce protein digestibility.

Brazil nut meal and spray-dried egg powders as alternatives to synthetic methionine in organic laying hen diets

The United States organic poultry industry is currently facing a limitation on dietary inclusion of synthetic methionine (Met). This study investigated Brazil nut protein powder (BNPP), spray-dried egg white (SDEW), and spray-dried egg blend (70:30 albumen: yolk) (SDEB) as alternatives to synthetic Met in organic laying hen diets. A total of 270 Hy-Line Brown laying hens was fed 5 diets from 22 to 38 wk of age, with 6 replicates of 3 adjacent cages per diet and 3 hens per cage. Diets included a commercial control (COM) (non-organic with standard CP and synthetic Met), an organic control (ORG) (with no synthetic Met, but higher CP to meet Met requirements), and 3 organic treatment diets with no synthetic Met, but including BNPP, SDEW, or SDEB at levels to meet Met requirements. Egg production and quality, body weight (BW), feed intake, and manure nutrients and ammonia were assessed. Data were analyzed using the PROC MIXED procedure of SAS, with Tukey's test used for multiple mean comparisons, and P ≤ 0.05 was deemed statistically significant. Body weight was greatest for the COM diet, and feed conversion improved for hens fed egg-based diets compared to controls. Egg weight and production did not differ between COM and treatment diets. The SDEW diet had greater albumen height and Haugh units compared to ORG and BNPP diets and greater percent albumen compared to COM and BNPP diets. Specific gravity was greatest for BNPP fed hens. Manure DM and potash were highest from COM and BNPP diets, respectively. Both egg-based diets increased ammonia flux relative to the COM diet. The BNPP and egg-based diets were lower in cost for $/metric tonne, $/dozen eggs, and $/kg of eggs compared to the ORG diet. The ingredients assessed herein could, therefore, cost-effectively replace synthetic Met in organic hen diets without negatively impacting egg production.