Use of probiotics and botanical extracts to improve ruminant production in the tropics: A review

Abstract

Ruminant production, especially in the tropics and developing countries suffers a setback when compared with the temperate and developed countries, which is attributable to the kinds of available feed resources in the region of production. In the tropics, ruminants are restricted to grazing on low-quality forages, crop residues and agro-industrial by-products with very little or no concentrate diets, which adversely affect the animals in exhibiting their full production potential. Considering this fact, there is an increasing interest in improving the digestibility of these feed resources. In recent years, researchers have explored several methods to enhance the functions of rumen microflora, improve digestion and fermentation processes, as well as increase bioavailability and utilization of nutrients through feed supplementation. This review aims to explore the positive effects of supplementation of ruminant diets with probiotics or botanical extracts and their metabolites on the productivity of the animals. Moreover, the functions of these non-pathogenic and non-toxic live microorganisms (probiotics) and plant biologically active compounds (botanical extract) are explored because of the ban on non-therapeutic use of antibiotics as growth promoters coupled with the critical preference of consumers to high quality and safe animal products. It has been reported that these alternative supplemental products have a beneficial impact on both animal health and productivity, which is affecting stabilization of rumen environment, inhibition of pathogenic bacteria proliferation in gastro-intestinal tract, modulation of immune response, increase in fibre degradation and fermentation, nutrients availability and utilization, animal growth performance and milk production, among others. However, long-term in vivo studies are still required to determine the synergetic effects of these 2 safe supplemental products.

Novel Crabtree negative yeast from rumen fluids can improve rumen fermentation and milk quality

“…The ruminal bacterial populations depend on sufficient nutrients or stimulants supply 38 . Yeast is a great supply to stimulate bacteria because it is enriched in essential substances 40 . Previous studies have confirmed that yeast could supply essential amino acids, vitamins, and minerals to increase the ruminal bacteria more than without yeast 41 .…”

Polyherbal feed additive for lambs: effects on performance, blood biochemistry and biometry

“…Some researchers have reported that secondary metabolites of plants can decrease methanogenic archaea, deriving the hydrogen for propionate formation (Frankič et al 2009;Holtshausen et al 2009;Oskoueian et al 2013;Arowolo and He 2018) and considering the plants in the polyherbal and its metabolites and an increase in propionate and a reduction in methane was expected (Kamra et al 2006;Mirzaei and Venkatesh 2012), however results suggests that butyrate-producing bacteria were stimulated by an unknown mechanism; Butyrivibrio represent among 10-30 % of culturable rumen bacteria in ruminants; molecular studies have identified other novel bacteria which can produce butyrate (Kopečný et al 2003).…”

Isolation and Characterization of Yeasts from Rumen Fluids for Potential Use as Additives in Ruminant Feeding

“…Yeast’s important roles include oxygen scavenging by reducing the amount of oxygen in the rumen and increasing the survival of other anaerobic microorganisms supplying essential nutrients such as mannooligo saccharide, protein or protein amino acid chelates, vitamins (B-complex), and minerals to other microorganisms upon cell lysis in the rumen; yeast can also stimulate the immune system in the hindgut [ 3 ]. These mechanisms affect animals by leading to maximum microbial population in the rumen, which increases their effectiveness in terms of their subsequent productivity [ 4 ]. Previous studies have confirmed that supplementation of S. cerevisiae as a direct feed can improve animal performance [ 5 ].…”