Dietary Inclusion of Guar Meal affects Broiler Performance and Immunity

Guar meal is the residual part of guar plant after production of guar gum. It is considered as a relatively inexpensive protein source for poultry. The crude protein level of guar meal varies according to fraction type¹. It has arginine content nearly twice that of soybean meal which makes guar meal economically useful as a partial replacement for soybean meal in poultry diets².

The use of guar meal at high levels in poultry diets has been limited due to its adverse effects which include diarrhea, decreasing growth rate and increasing mortality³. These adverse effects might be attributed to the presence of some anti-nutritional compounds in guar meal⁴.

β-mannans are considered powerful anti-nutritional factors for mono-gastric animals, increasing digesta viscosity and decreasing nutrient digestibility in broiler chicken⁵. β-mannanase is a fermentation product of Bacillus lentus that degrades β-mannans in broiler feed⁶.

The use of a β-mannanase has been shown to improve feed: gain and reduce water: feed ratio, leading to drier fecal output. Its supplementation to the broiler’s diet resulted in decreased intestinal viscosity and increased growth and feed efficiency. Therefore, a new was carried out study was to investigate the effect of partial replacing soybean meal with 5% guar meal with or without β-mannanase supplementation on growth performance, carcass traits,  serum biochemical and immunological parameters of broiler chickens⁷.

It was observed that the addition of 5% guar meal to broiler diets reduced final body weight and feed efficiency. An improvement in immune response of broiler chickens with dietary inclusion of 3 and 6% guar meal with and without β-mannanase supplementation was found.

The results of serum alkaline phosphatase, ALT, AST, uric acid and creatinine indicate that both guar meal and β-mannanase supplementation had no effect on liver and kidney functions. From the results, it could be concluded that GM could be applied at 5% in broiler diets with β-mannanase supplementation maintaining the same broiler performance parameters and with improve bird immune response.

The study discovered the beneficial effect of β-mannanase enzyme supplementation to broiler diet containing guar meal in improving broiler performance and immunity. It will help to uncover the critical area of using inexpensive protein source like guar meal in broiler diet with maintaining production level. Thus, a new theory on using guar meal as a partial replacement for soybean meal in poultry diet with β-mannanase supplementation for decreasing feed cost with maintain the performance parameters may be arrived.

Keywords:

Beta-mannanase, guar meal, broiler, growth parameters, immunity, decreasing feed cost, poultry diet, performance parameters, serum alkaline phosphatase, ALT, AST, uric acid and creatinine.

References:

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