Replacement value of cassava for maize in broiler chicken diets supplemented with enzymes

Meta-analysis of substitution value of maize with cassava (Manihot esculenta Cratnz) on growth performance of broiler chickens

There are variable results on the effect of cassava on the performance characteristics of broiler chickens. As a result, this meta-analysis was performed to determine the effect of cassava on feed intake, feed conversion ratio (FCR), and average daily gain (ADG) in broiler chickens. A methodical search performed on Google Scholar, Scopus, Web of Science, and PubMed databases as well as individual journals yielded 365 published articles. Out of 365 studies, 23 that met the inclusion criteria were used for the meta-analysis. Outcome measures were pooled using a random-effects model. Results were expressed as standardized mean differences (SMD) at 95% confidence intervals (CIs). Subgroup and meta-regression analyses were used to explore the effects of studied covariates (broiler strain, inclusion level of cassava, number of broilers per replicate, cassava processing methods, and cassava form) on measured outcomes. Results indicated that cassava had a small positive effect on feed intake (SMD = -0.07, 95% CI -0.26, 0.12) and FCR (SMD = 0.14; 95% CI 0.82, 1.746), but a large negative effect on ADG (SMD = -1.67; 95% CI -1.99, -1.35) compared to the controls. Subgroup analysis by cassava form showed that wet fermented cassava peel meal (WFCPM) had a moderate impact on feed intake (SMD = 0.62, 95% CI 0.47, 0.77) and ADG (SMD = 0.66, 95% CI 0.37, 0.95) in broiler chickens compared with the controls. Our results also found improved growth performance in broiler chickens fed cassava at 4-10%. There is evidence of between-study variance, and studied covariates explain most of the sources of heterogeneity. This study concluded that the replacement of maize with 4-10% WFCPM improved growth performance traits in broiler chickens.

The effect of the use of cassava tuber (Manihot esculenta) and Indigofera zollingeriana leaf flour combination as a source of energy supplemented with citric acid in ration on broiler small intestine characteristics and productivity

OBJECTIVE

The study aimed to determine the effect of using a combination of cassava tuber (Manihot esculenta) and Indigofera zollingeriana leaf flour as an energy source supplemented with citric acid in the ration on performance, carcass quality, digesta pH, viscosity, and the number of villi in the intestines of broilers.

MATERIALS AND METHODS

The research design was completely randomized with five treatments and five replications, each containing four broilers. The treatment was a substitution of corn in the ration with a combination of cassava tuber and I. zollingeriana leaf (CIF): without CIF, 5% CIF substitute for corn + 0.2% citric acid, 10% CIF substitute for corn + 0.2% citric acid, 15% CIF corn substitute + 0.2% citric acid, and CIF corn substitute + 0.2% citric acid. Each treatment ration was supplemented with 0.2% citric acid. The variables that were looked at were ration consumption, body weight gain, feed conversion, live weight, percentage of the carcass, percentage of abdominal fat, pH, viscosity, and the number of broiler villi.

RESULTS

This study showed that the combination of CIF flour supplemented with 0.2% citric acid had a significant effect (p < 0.05) on body weight gain, ration conversion, live weight, carcass percentage, and the number of villi in broiler intestines. But it did not have a significant effect (p > 0.05) on the amount of feed eaten, the amount of fat in the abdomen, the pH of the digesta, or the thickness of the broilers' blood.

CONCLUSIONS

The combination of CIF flour at a level of 10% supplemented with 0.2% citric acid can be used as an energy source to replace corn without having a bad effect on production performance, carcass quality, and small intestine characteristics of broilers.

A review of limitations to using cassava meal in poultry diets and the potential role of exogenous microbial enzymes

Cassava (Manihot esculenta), a crop grown in the tropics, is increasingly becoming a vital feed resource for human beings and livestock. Traditionally, cassava has been used primarily as a source of food for humans. However, it is becoming an increasingly important ingredient in livestock feed. The use of cassava leaves and roots in poultry diets is limited because of nutrient imbalances and toxins (hydrogen cyanide (HCN)) found in them. High HCN is reduced to innocuous levels by processing the ingredient using a simple sun drying method. Plant fibre content can be reduced and made available for use by poultry through the use of exogenous enzymes. More recent innovative interventions in biotechnology have brought about various exogenous enzymes that can help improve the digestibility of fibrous diets. These include, among others, carbohydrases, proteases and phytases. The extent to which the animals utilise nutrients is influenced by the type of enzyme and the physicochemical properties of the feed ingredient. This review aims to collate information on the current state of knowledge on the use of exogenous microbial enzymes in diets containing cassava and how the enzymes that target carbohydrates might be useful in making nutrient available for poultry.