Effects of fermented cottonseed meal on the growth performance, gastrointestinal microflora population and small intestinal morphology in broiler chickens.

1. This experiment was conducted to evaluate the effects of replacing dietary cottonseed meal (CSM) or fermented cottonseed meal (FCSM) for soya bean meal (SBM) on growth performance, carcass characteristics, gastrointestinal microbial populations, and intestinal morphology of broiler chickens. 2. CSM was fermented with Bacillus subtilis, Aspergillus niger and A. oryzae for 7 d. A total of 300 one-d-old male Ross 308 broiler chickens were used in a 42-d experiment in which the birds were randomly allotted to one of 5 dietary treatments (containing 0%, 10% and 20% CSM or FCSM) in a completely randomised design. Birds were reared on litter floor and had free access to feed and water during the experiment. 3. Results indicated that the fermentation process significantly reduced crude fibre and free gossypol, while it increased crude protein content and lactic acid bacteria (LAB) count in CSM. 4. The use of FCSM instead of CSM significantly improved growth performance of broilers. The abdominal fat yield in treatments containing FCSM was significantly lower than in the other treatments. The increase in the population of LAB in the crop and decrease in the population of coliforms in the ileum of birds fed on diets containing FCSM were more significant than in other birds. Villi in the duodenum and jejunum of the birds fed on diets containing FCSM were significantly higher than for the other experimental groups. 5. The positive effects of diets containing FCSM on growth performance and intestinal health of broiler chickens showed that this processed source of protein can serve as an appropriate alternative for SBM in diets for broiler chickens.

Effects of enzyme supplement on nutrient digestibility, metabolizable energy, egg production, egg quality and intestinal morphology of the broiler chicks and layer hens fed hull-less barley based diets.

The effects of beta-glucanase (550 U g(-1)) and xylanase (800 U g(-1)) supplementation on the nutrient digestibility and metabolizable energy of egg production, egg quality intestinal morphology of the broiler chicks and layer hens fed hull-less barley-based diets were examined in three similar experiments. The results of this study showed that the inclusion of beta-glucanase and xylanase in the hull-less barley based diets had no significant improvement on the growth performance of broiler, feed conversion ratio. The results of this experiment showed that beta-glucanase and xylanase had negative effects on egg shell quality as reduced egg shell weight (4.6%) and egg shell thickness (5.32%). The addition of beta-glucanase and xylanase had also no effects on yolk color and Hugh units of eggs either. The results also demonstrated that beta-glucanase and xylanase supplementation did not improve the metabolizable energy, organic matter, protein and starch digestibility of the diet contained hull-less barley. The addition of glucanase and xylanase to the diets significantly reduced villus height, villus width, crypt depth, villus height: crypt depth ratio and goblet cell numbers of the duodenum and jejunum of small intestine compared with the control group. But, the numbers of goblet cells were more in the jejunum than in duodenum of small intestine. On the other hand, these enzymes reduced villus width and crypt depth of the ileum while increased villus length of the ileum receptivity. The goblet cells numbers in the villi of the ileum of birds fed the hull-less based diet; with exogenous enzyme were significantly higher than those in the jejunum and duodenum section of small intestine of layer hens. Goblet cells are responsible for the secretion of mucin that is used for the mucinous lining of the intestinal epithelium. Further studies are needed to evaluate the effects of exogenous enzyme on the nutrient digestibility, metabolizable energy, intestinal morphology and microflora activity of intestine of the broiler chickens and layer hen diet.

Influence of level of feed input and procedure on metabolisable energy and endogenous energy loss (EEL) with adult cockerels.

1. Two experiments were performed to study the relationship between apparent metabolisable energy (AME) and true metabolisable energy (TME) values at different feed intakes. Rhode Island Red (RIR) adult cockerels were used in two bioassays, under standard conditions. 2. In the first experiment (precision feeding) the birds were not fed for 24 h and then various quantities of maize were fed. There were 6 replicates per treatment. Droppings voided during the 48 h of the experimental period were collected and assayed for gross energy and nitrogen. 3. In the second experiment, each bird was given a 3-d adaptation period, fasted for 24 h and then given maize as an admixture (conventional addition method: CAM) to the same rations as those used in the first experiment. During the 3 d of the experimental period, droppings were collected and frozen for chemical analysis. 4. The results showed that mean metabolisable energy (ME) values obtained by the precision-feeding procedure were higher than those obtained by CAM. The endogenous energy loss (EEL) (FEm + UEe) determined by precision feeding was lower than that given by CAM. 5. It was concluded that the method of feeding does not influence ME of maize at different feed inputs. However, differences among intercepts of the regression between ME and feed input suggest that EEL varies at different maize inputs. 6. The optimum maize quantity was approximately 35 to 40 g for adult RIR cockerels by both procedures.

Comparison of inert markers [chromic oxide or insoluble ash (Celite)] for determining apparent metabolizable energy of wheat- or barley-based broiler diets with or without enzymes.

A broiler chick bioassay was used to measure the effect of two inert digestibility markers on the determination of dietary AME. Diets contained 80% of either wheat or barley (with or without enzyme) and either chromic oxide at 0.5% or one of three levels of insoluble ash (0.5, 1.0, or 1.5%) as markers. The various cereal and marker diet combinations were consumed ad libitum (0 to 21 d) by two groups of 10 male broilers in each of two trials. The AME of each diet was determined by measuring the respective marker ratios between diet and excreta (collected for 24 h at 7 or 21 d) or ileal digesta collected at 21 d. Growth and feed conversion were measured on each group of birds between 0 and 21 d. There was no effect of marker on growth or feed efficiency. However, determination of AME of wheat- or barley-based diets with or without enzymes were affected by choice of marker and whether markers were measured in excreta (7 or 21 d) or ileal digesta. Chromic oxide was viewed as the least accurate method for determining AME, based on chronic oxide's inability to define AME differences between barley-based diets with and without enzymes, whereas insoluble ash clearly demonstrated improved AME of wheat- and barley-based diets with an enzyme. The optimum levels of insoluble ash for accuracy and repeatability were between 0.5 and 1.0%. The AME of the diets were, on average, 5% lower when determined with 7 vs 21 d excreta and 2.5% lower for ileal digesta than excreta collected at 21 d. It was concluded that identification of components that result in variability in AME levels of diets will be improved if a bioassay uses insoluble ash as a marker.

True metabolizable energy values of corn and different varieties of wheat and barley using normal and dwarf single comb White Leghorn Roosters.

An experiment with four trials was conducted to measure the true metabolizable energy value of corn and different varieties of wheat and barley using normal and dwarf Single Comb White Leghorn (SCWL) roosters. Maxigene, Purple, Red, and Yamhill wheats and corn were assayed for TME using normal sized and dwarf roosters in Trials 1 and 2, respectively. Hannchen, No. 2 Western, Lady Godiva, and Hiproly barleys were assayed using normal sized and dwarf SCWL roosters in Trials 3 and 4, respectively. The pooled results indicated that normal sized roosters gave (P less than .01) significantly higher TME values than dwarf roosters. There was no significant difference in TME found between wheat and barley cultivars, although both types of grain were significantly (P less than .01) lower in TME than the value found for corn. Average dry matter TME values for corn, wheat, and barley were 4.17, 3.70, and 3.54, respectively. A bird x grain interaction was found to be significant (P less than .05).