Significance of single β-mannanase supplementation on performance and energy utilization in broiler chickens, laying hens, turkeys, sows, and nursery-finish pigs: a meta-analysis and systematic review

Abstract

This review will give a brief description of β-mannans, abundance in feedstuffs, utility of supplemental feed β-mannanase and subsequent animal responses. Soybean products and co-products of processing palm, coconut and guar seeds are the major sources of β-mannans in poultry and livestock feed. β-mannans are linear polymers of mannose residues linked by β-1,4 glycosidic bonds and their ingestion elicit undesirable and metabolically costly responses. Web of Science was searched to retrieve published studies for meta-analyses of the impact of supplemental β-mannanase on performance and digestibility in pigs and poultry. The mean difference (MD) between ß-mannanase and control on average daily gain (ADG, g/d) was +0.23 (P=0.013; 95% CI 0.05; 0.41), +10.8 g/d (P=0.0005; 95% CI of 6.6; 15.0 g/day) and +20.68 (P<0.000; 95% CI of 17.15; 24.20 g/day) for broiler chickens, nursery pigs and grow-finish pigs, respectively. The MD on β-mannanase improvement on FCR was -0.02 (P<0.0001) with 95% CI (-0.03; -0.02) suggesting a 2-to-3-point FCR improvement in broiler chickens. ß-mannanase improvement on gain to feed (G:F) was +13.8 g/kg (P=0.027; 2.1; 25.4 g/kg) and +8.77 g/kg (6.32; 11.23 g/kg) in nursery and grow-finish pigs, respectively. β-mannanase improved AMEn by 47 kcal/kg (P=0.0004) with 95% CI (28.8; 65.7 kcal/kg) in broiler chickens. The improvement of gross energy digestibility in pigs was 1.08 percentage unit with 95% CI (0.90; 1.26) translating to the release of between 30.6 and 42.8 kcal/kg of digestible energy. Although data was limited, β-mannanase improved egg production but had no impact on egg quality in laying hens. Turkeys may be more adversely affected by ß-mannans because of the high protein/ amino acids requirements necessitating higher dietary inclusion of soybean meal. However, growth performance and feed efficiency responses of turkeys fed diets supplemented with β-mannanase was variable. In summary, ß-mannanase supplementation improved performance linked to energy and nutrient utilization. However, the magnitude of response was variable within and between species indicating further application refinement is warranted to achieve consistent efficacy, including an improved understanding of the functional contribution of β-mannans hydrolysis products.

Does supplementing β-mannanase modulate the feed-induced immune response and gastrointestinal ecology in poultry and pigs? An appraisal

“…Protein feedstuffs are particularly rich in b-mannans, a type of hemicellulose rich in Dmannose units linked in b-(1-4) glycosidic bonds (Chen et al, 2018a). We recently reported the structure, abundance, and nutritional implications of b-mannans in common feedstuffs (Kiarie et al, 2021). In general, the major b-mannans in feedstuffs are glucomannan and galactomannan, and the concentration can be as high as 30% DM in some feedstuffs (Kiarie et al, 2021).…”

“…We recently reported the structure, abundance, and nutritional implications of b-mannans in common feedstuffs (Kiarie et al, 2021). In general, the major b-mannans in feedstuffs are glucomannan and galactomannan, and the concentration can be as high as 30% DM in some feedstuffs (Kiarie et al, 2021). Figure 1 illustrates the framework for gastrointestinal and ecology responses to intact feed b-mannans.…”

“…However, the utility in animal nutrition is dependent on the mechanism of action (Kiarie et al, 2013). For example, feed bmannanase has been demonstrated to benefit growth performance and digestibility in pigs and poultry, as summarized in numerous reviews (Shastak et al, 2015;Torres-Pitarch et al, 2019;Saeed et al, 2019;Kipper et al, 2020;Kiarie et al, 2021). However, native/intact feed b-mannans, the target substrate for bmannanase, not only have anti-nutrient properties but have also been linked to stimulating immune responses with implications on post-absorptive nutrients utilization.…”

Effect of β-Mannanase Addition during Whole Pigs Fattening on Production Yields and Intestinal Health

“…One of the findings of this study is the difference in ADFI during the growth period. In a meta-analysis on the effects of β-mannanase in different species, Kiarie et al [ 42 ] note that there is no difference for this parameter. The same authors observed a mean difference of 10.8 g/d, while in our study a difference of 74 g/d on behalf of CON in the growing period and 43 g/d for HC in the finishing period was observed.…”

Analysis of merged transcriptomic and genomic datasets to identify genes and pathways underlying residual feed intake in growing pigs

“…FE in pigs is a complex trait with a large number of biological and environmental components. Environmental factors such as feed composition are constantly studied, leading to new understanding and advances in the optimization of feed composition (4,5). Furthermore, advancements in molecular biology techniques have led to many/several studies directed at identifying the biological components involved in FE in pigs.…”