Bacterial clearance, heterophil function, and hematological parameters of transport-stressed turkey poults supplemented with dietary yeast extract

Abstract

Yeast extracts (YE) contain biological response modifiers that may be useful as alternatives to antibiotics for controlling pathogens in poultry production and mitigating the deleterious effects of production stressors. The objective of the present study was to determine the ability of a commercial dietary YE (Alphamune) to modulate the immune response in male turkey poults challenged with Escherichia coli and subjected to transport stress. Alphamune was added to turkey poult diets at 0, 500, or 1,000 g/ton. Poults were challenged by air sac injection with 60 cfu of E. coli at 1 wk of age. At 3 wk of age, these challenged birds were subjected to transport stress and birds were bled and necropsied the following morning. Blood cell numbers and percentages, hematological parameters, and clinical chemistry values were determined. Oxidative burst activity of isolated heterophils was measured using stimulation with phorbol myristate acetate and a 2',7'-dichlorofluorescein diacetate assay. Data were analyzed using GLM and least squares means procedures of the SAS program. The numbers and percentages of heterophils in peripheral blood were increased and their oxidative burst activity was stimulated by YE. The stress challenge dramatically increased oxidative burst and this increase was significantly modulated by YE treatment. Serum levels of calcium, phosphorus, and triglycerides were decreased and uric acid levels, erythrocyte numbers, hemoglobin, and hematocrit were increased by YE supplementation. Bacteria were isolated from the air sac and liver of a lower percentage of birds provided with YE. These results suggest that dietary YE has potential as a nonantibiotic alternative for decreasing bacterial pathogens in turkey production.

Beta-Glucans as Immunomodulators in Poultry: Use and Potential Applications

“…We found an increase in the heterophil to lymphocyte ratios in Eimeria-challenged birds fed 0.02% bglucan (Cox et al, unpublished data). Treatment of turkey poults with a yeast extract containing bglucans resulted in similar findings where the percentage of heterophils and their oxidative burst activity was increased (Huff et al, 2010). Accordingly, the heterophil to lymphocyte ratios were also increased (Huff et al, 2007(Huff et al, , 2010.…”

“…Feed intake was again raised with the b-glucan supplemented diet. Other research laboratories, including ours, reported similar results where no deleterious effects were observed due to dietary bglucan supplementation in broilers (Cheng et al, 2004;Chen et al, 2006;Chen et al, 2008;Cox et al, 2010a,b;Morales-Lopez et al, 2009) or turkey poults (Huff et al, 2010).…”

“…Treatment of turkey poults with a yeast extract containing bglucans resulted in similar findings where the percentage of heterophils and their oxidative burst activity was increased (Huff et al, 2010). Accordingly, the heterophil to lymphocyte ratios were also increased (Huff et al, 2007(Huff et al, , 2010. Huff and colleagues (2010), however, found that poults subject to an E. coli challenge and transport stress exhibited decreased oxidative burst activity of heterophils when fed yeast extract.…”

Exploring alternatives to antibiotics as health promoting agents in poultry- a review

“…Saccharomyces known to offer a source of good quality protein and B complex vitamins. Due to immunomodulatory properties, yeast extract, the non-antibiotic functional product is suggested to be the potential non-antibiotic alternative for decreasing pathogenic bacteria in turkey production (Huff et al, 2010). Currently, yeast cell derivatives are gaining importance as zootechnical feed additives (Świątkiewicz et al, 2014).…”

The Visceral Organ, Gastrointestinal Tract and Blood Characteristics in Pegagan Ducks Fed Ration Fermented by Tape Yeast with Different Moisture Content

“…It is known that the high nutrient digestibility will affect the activity of visceral organs and digestive tract, which can be measured by weight changes (Hetland et al, 2005). In addition, this will also affect the increase of erythrocyte numbers, hemoglobin and hematocrit (Huff et al, 2010), as well as stimulate the immune system to generate more antibodies (Shanmugasundaram et al, 2013). Based on this, further studies to find out the effect of feeding the local ration fermented by tape yeast with different moisture content on bird's performances need to be implemented.…”