ABSTRACT The objective of this study was to evaluate the effect of using exoenzyme phytase in broiler's diets on digestibility of nutrients, feed energy and tibia bone mineralization. A completely randomized design was used, with the following treatments: sorghum with dicalcium phosphate (SDP), corn with dicalcium phosphate (CDP), sorghum with meat and bone meal (SMBM), sorghum with valued phytase (SVP) and sorghum with phytase without valued (SPWV). For digestibility analysis, eighty 15 day old broilers were used, a total of 1400 male Hubbard Flex chickens, which were submitted to total excreta collection to obtain the percentages of food digestibility, crude protein, ether extract, apparent metabolizable energy, calcium and phosphorus while for tibias mineralization. Six birds per treatment were used, where determination of mineral matter, calcium and phosphorus were performed. Metabolizable energy (ME) and apparent metabolizable energy corrected for nitrogen (AMEn) of the feed were also calculated. Data were subjected to variation analysis and the average compared by 5% Tukey test. There was no difference between treatments for the digestibility at 15-20 day old as well as for the feed energy values, but the diets with phytase had higher phosphorous percentage values for tibia bone mineralization, demonstrating that exogenous phytase enzyme is able to hydrolyze phytate origininated from plant and release the phosphorus for assimilation by animals, acting as a substitute for phosphorus plant sources.

ABSTRACT An experiment was conducted to compare three nutritional programs, which were developed with tannin-free grain sorghum based diets, evaluating performance, carcass yield and bromatological composition of the pectoral muscle of broilers. A total 1360 chicks mixed (50:50), from one to 42 days old Hubbard Flex Broilers, were housed in a completely randomized design consisting of treatments and 10 replicates each, distributed as follows: three programs with whole sorghum grain based diets (nutritional program with daily adjustment, nutritional program with every three days adjustment and nutritional program with four stages and a program with ground and whole sorghum grain based feed (four stages). The cumulative performance was evaluated at, 21 and 42 days, determining feed intake, weight gain, feed conversion and viability. At 42 days, the yield of eviscerated carcass, breast (full and boneless), thighs/drumsticks and wings and breast composition were evaluated. Nutritional adjustments showed better feed conversion, did not affect the carcass, commercial cuts yield and had a good breast meat quality. It can be concluded that daily feed programs could be performed in poultry industry with the mixture of whole sorghum grains and concentrates directly on farms contributing to better logistics and feed transportation cost.

ABSTRACT The objective of the study was to evaluate the effect of nutritional plans on the productive and economic performance of Hubbard Flex broiler chickens. A completely randomized experimental design was applied, consisting of five treatments. Treatments consisted of five different nutritional plans: a basal diet containing the nutrient and energy levels recommended by literature and designated reference diet; two diets containing 1.5% and 3% lower levels than the reference diet; and two diets containing 1.5% and 3% higher levels than the reference diet (-3%, -1.5%, reference plan, +1.5% and +3%). Feed intake (FI), body weight (BW), feed conversion rate (FCR), livability (L) and productive efficient index (PEI) were determined when broilers were 42 days old. Broilers were processed, and carcass and parts (breast fillet, leg, and wings) yields were determined. The economic viablility of the nutitional plans was evaluated as a function of feed cost/kg live and carcass weights, economic efficiency index (EEI), and cost index (CI). Feed intake and the feed conversion rate decreased as dietary nutrient and energy levels increased. Feed cost/kg live weight, economic efficiency index, and cost index cost increased as dietary nutrient and energy levels increased. Feed intake, feed conversion ratio, production efficiency index, and breast yield improved with increasing nutritional and energy levels. However, worse economic results were obtained with higher nutritional and energy levels.

This study aimed at evaluating the effects of whole and ground sorghum, compared with ground corn, on the live weight, feed conversion ratio, organs weight and intestinal biometrics and histomorphometrics. In total, 960 Hubbard Flex broilers were reared until 42-day-old and distributed into 24 pens, according to the three treatments: ground corn, whole-grain sorghum, and ground sorghum. On day 42, five male birds per treatment were selected by similar body weight and sacrificed. Gizzard absolute weight, and proventriculus, liver, pancreas and heart relative weights, and duodenum, jejunum, ileum, ceca, and colon length and relative weight were determined. Villus characteristics and intestinal mucosa absorption surface area were evaluated. Broilers fed sorghum, independently of physical form, were heavier and had greater feed conversion ratio than those fed ground corn. Gizzard showed the highest relative weight in broilers fed whole sorghum compared to corn. Liver and jejunum relative weight was higher in broilers fed ground corn, compared to ground sorghum. Whole small intestine, cecum and colon relative lengths showed no difference among treatments. Deeper crypts were found in the duodenum of broilers fed whole grain sorghum, compared to ground sorghum, as well as in jejunum compared to ground corn; however, intestinal absorption surface area was not different among treatments. Whole or ground grain sorghum may replace corn in the feed of 1- to 42-d-old broilers, since they improve body weight and feed conversion ratio, and not adversely affect intestinal morphometry and organs weight.