Yeast-Derived Mannan Supplementation has Positive Effects on Immunity of Calves

Review Article

Austin Food Sci. 2020; 5(2): 1039.

Yeast-Derived Mannan Supplementation has Positive Effects on Immunity of Calves

Vaclav V¹* and De Oliveira Carlos AF²

¹Department of Pathology, University of Louisville, USA

²Department of Research and Development, Biorigin Company, Brazil

*Corresponding author: Vaclav Vetvicka, Department of Pathology, University of Louisville, USA

Received: May 25, 2020; Accepted: June 18, 2020; Published: June 25, 2020

Abstract

Farming faces numerous challenges: 1) emerging new diseases 2) current efforts to ban growth-promoting antibiotics 3) improve conditions and overall health of the farmed animals. This situation opens new opportunities for natural, highly effective and cost affordable immunomodulators. We evaluated the immunostimulative effects of a novel, yeast-derived mannan supplementation on health status of calves. Our results showed that 30-day supplementation resulted in significant improvements and offered two significant benefits: natural protection and natural growth stimulation.

Keywords: Immune; Mannan; Cattle; Cortisol; Phagocytosis; IL-2

Introduction

The immune system in general and innate immune system in particular, is fairly well conserved among all vertebrates. Neonatal calves’ intestinal tract develops immune mechanisms via passive and innate components of immunity. The health status of young calves is one of the most important factors contributing to their growth. A major issue is diarrhea, most often caused by Escherichia coli infection. Early stimulation of innate immunity is an important method to enable calves to thrive after maternal antibodies have waned and before their specific immunity is fully developed.

One possibility is the use of natural immunostimulants such as glucan or mannan.Glucan’s role as an immunomodulator has been well documented for over 50 years. β-Glucans show notable physiological effects; this is their most important quality and the reason why so much attention has been focused on them. β1,3- glucans, either particulate or soluble, exhibit immunostimulating properties, including antibacterial and anti-tumor activities [1,2]. Despite the fact that glucan has been intensively used in farm animals; the information on its effects in calves is sporadic.An interesting study showed that glucan addition to the vaccine-increased immune response [3]. Another study found improvements in milk quality and changes in cytokine expression after glucan administration [4]. A glucan-ascorbic acid combination modulated immune functions, particularly lung cell populations [5].

In the yeast cell wall, glucomannans are present in complex molecules usually linked to a protein moiety. Depending on isolation and size, the biological and immunological functions can vary [6]. One of the most studied components is Bio-Mos, a mannan oligosaccharide [7]. Glucomannan consists of glucose and mannose units joined by glycosidic linkages (via different positions and in different ratios). Similar to isolated glucans, glucomannan showed a broad range of biological activities including radioprotection, antimutagenic properties, anti-oxidative and immunostimulatory effects [8,9]. Readers seeking more information of immunological activities of various polysaccharides should seek an excellent review [10].

In this study, we evaluated the effects of a new generation of yeast wall containing soluble mannan and partial exposure of the beta-glucan layer into commercial feed of calves. We measured Body Weight (BW), changes in phagocytic activity, levels of cortisol after LPS challenge and effects of E. coli infection.

Material and Methods

Animals

At the onset of our study, all animals were evaluated for signs of any disease and all were considered healthy based on lacking any relevant abnormalities. Animal care and use was approved by the IACUC committee. Thirty calves (20 days old; 35±1, 5 kg of BW) were used for a 30-day experimental period. The animals were kept in individual pens. Weekly body weight was recorded and treatment dosages were adjusted accordingly.

The animals were chosen randomly forthe experimental treatments: Control, without yeast wall; or Mannan, with addition of 100 mg/kg BW yeast wall (Hypergen; BioriginCompany, Brazil) by gavage (Figure 1). On day 30 of experimentation, five animals in each group received LPS; fivemore animals in each group were challenged orally with E coli (see below). Composition of the feed is shown in Table 1. All animals were grown in conventional conditions.