Resumo em Inglês:

ABSTRACT The meal of Jatropha curcas (JCM) seed is a by-product of the biofuel industry and may potentially to be used as animal feed. However, its toxicity has prevented its utilization in animal nutrition mainly due to its high concentration of phorbol esters. This study was conducted to evaluate the effects of the dietary inclusion of JCM on the growth performance, feed digestibility and internal organs development of broilers. Thirty two 48-d-old Ross 308 broiler chickens housed in 16 pens (2 birds/pen) were used in this study. Birds were randomly allocated to dietary treatments comprising four JCM levels (negative control, 25, 50, or 100 g JCM/kg of diet) for four weeks. Results showed that increasing levels of JCM had a negative impact on broiler performance, reducing live weight, weight gain, and feed intake. Treatments led to a decrease of the relative weight of testis and spleen, and to an increase in heart relative weight. In broilers fed diets containing JCM, the testis were atrophic, presenting reduced size of the seminiferous tubule, which were small and lined within active sertoli cells and rare spermatogonia. This study illustrates the negative impact of diets containing JCM on broiler performance and JCM pathological effects on several organs.

Resumo em Inglês:

ABSTRACT The aim of this study was to evaluate the efficacy of a yeast glucomannan (YG) and sodium bentonite (SB) in reducing the toxicity of aflatoxin for broilers fed a diet naturally contaminated with aflatoxin. In total, 300 7-day-old Ross 308 broilers were randomly assigned to 10 dietary treatments, consisting of a diet with no aflatoxin (positive control), a diet naturally contaminated with 250 ppb aflatoxin (negative control), and eight aflatoxin-contaminated diets supplemented with different SB and YG and their combinations. Serum biochemical parameters and liver pathological changes were investigated when broilers were 42 days old. The birds fed the negative control diet presented lower uric acid, cholesterol, and triglyceride levels and higher in AST and ALT activities compared with the positive control group. In addition, negative-control birds also showed significant histopathological changes (p<0.05), including slight to moderate hydropic degeneration and/or fatty changes (8 cases), bile-duct hyperplasia (7 cases), periportal fibrosis (5 cases), cells infiltration (4 cases), congestion (3 cases) as well gross pathological changes. The addition of YG and SB to the aflatoxin-contaminated diet partially alleviated the negative effects of aflatoxin. However, the supplementation 0.1% YG alone to the aflatoxin-contaminated diet significantly prevented the adverse effects of aflatoxin on serum biochemical parameters and pathological liver changes and was found to be more effective than other treatments.

Resumo em Inglês:

ABSTRACT An experiment was conducted with the purpose of evaluating enzyme blends on the performance, carcass traits, and bone mineralization of broilers. In total, 928 one-day-old Cobb 500 male chicks of were used. A completely randomized design with four treatments with eight replicates of 29 birds each was adopted. The evaluated treatments were: 1- Positive Control (PC), feed containing the nutritional recommendations of the genetic company's manual; 2- Negative Control (NC), feed with reductions of 75 kcal/kg AME and 0.10 and 0.12 percent points of phosphorus and calcium, respectively; 3 - NC + enzyme blend (amylase + b-glucanase, xylanase, and phytase; 250 g/t of feed) and 4 - NC + enzyme complex (phytase, amylase, xylanase, glucanase, pectinase, cellulase, and protease; 200 g/t of feed). Birds fed the diet with reduced nutrient levels (NC) presented the worst performance (p<0.05). The supplementation of the enzyme blend promoted similar (p<0.05) weight gain and feed conversion ratio as those obtained with the PC diet during the period of 1-21 days of age. During the phase of 22-42 days and the entire experimental period, weight gain and feed conversion ratio improved with the use of the enzyme combinations compared with the NC group, but remained lower than the PC group. Enzymes combinations did not affect (p>0.05) carcass or parts yields. The broilers fed the reduced-nutrient and energy diet presented lower (p<0.05) tibial ash, calcium, and phosphorus contents that the other treatments. The use of enzyme combinations improved the performance of broilers fed diets with reduced nutrient and energy levels.

Resumo em Inglês:

ABSTRACT The main objective of the present study was to evaluate the effects of the dietary addition of different levels of rosemary powder (RP) and vitamin E (VitE) on broiler performance and gut gross morphometry. A total of 270 one-day-old Ross 308 male chicks were randomly assigned to nine dietary treatments with three replicates of10 birds each. Treatments consisted of diets were supplemented with 0, 0.5 or 1.0% RP and 0, 100 or 200 mg/kg VitE (alpha-tocopherol acetate). Feed intake and weight gain were recorded weekly. On day 42, one bird per replicate was euthanized after blood sampling. Gastrointestinal tract segments were measured and/or weighed. Means were compared by least significant difference. Overall, broilers fed1.0% RP presented lower (p< 0.05) feed intake, weight gain, and final weight body than those fed 0.5% RP. Broilers fed the 0.5% RP plus 200 mg/kg VitE diet presented higher weight gain (p<0.05) in than those in the control group (0% RP and 0 mg VitE). Jejunum length and weight, colon length and width, and right cecum weight were also negatively affected (p<0.05) by the 1.0% RP diet when compared with the 0.5% RP diet. We suggest that the dietary supplementation of 0.5% RP plus 200mg/kg of vitE improves broiler performance and does not have significant adverse effects on gross gut morphometry. Dietary VitE may play a potential protective role against the negative effects of high levels of RP.

Resumo em Inglês:

ABSTRACT The aim of this study was to evaluate the effect of digestible threonine supplementation in the starter diet on the performance, intestinal parameters, and nutrient metabolism of broilers derived from breeders of different ages. In total, 480 one-day-old Cobb chicks, derived from 38-or 49-week-oldbreeders, were housed in experimental battery cages until 21 days of age and fed four different threonine levels (800, 900, 1,000, or 1,100 mg/kg) in the starter feed. A completely randomized experimental design in a 2x4 factorial arrangement (breeder age x threonine levels) was applied, totaling eight treatments with five replicates of 12 birds each. Broilers from older breeders fed 800 mg digestible threonine/kg of diet presented higher weight gain, with a positive linear effect. There was also an interaction between breeder age and threonine levels for the weight gain of 21-d-old broilers supplemented at maximum level of 1,003 mg Thr/kg diet during the starter phase. There was no effect of breeder age or threonine levels on nutrient metabolism during the period of 17-21 days. There was no influence of breeder age or threonine levels in the starter diet on intestinal morphometric measurements, absorption area, or percentage of goblet cells.

Resumo em Inglês:

ABSTRACT This experiment was carried out to evaluate the effect of different dietary supplementation levels of zinc oxide and of an organic acid blend on broiler performance, carcass traits, and serum parameters. A total of 2400 one-day-old male Ross 308 broiler chicks, with average initial body weight 44.21±0.19g, was distributed according to a completely randomized design in a 2 x 3 factorial arrangement. Six treatments, consisting of diets containing two zinc oxide levels (0 and 0.01% of the diet) and three organic acid blend levels (0, 0.15, and 0.30%) were applied, with eight replicates of 50 birds each. The experimental diets were supplied ad libitum for 42 days. There were significant performance differences among birds fed the different zinc oxide and organic acid blend levels until 42 d of age (p<0.01). The result of this experiment showed that the organic acid blend did not affect feed intake, but zinc oxide increased feed intake. Carcass traits were not influenced by the experimental supplements. Zinc oxide supplementation increased serum alkaline phosphatase level (p<0.01). The organic acid blend reduced serum cholesterol and triglyceride levels (p<0.05). No interactions were found between zinc oxide and the organic acid blend for none of the evaluated parameters. We concluded that zinc oxide and the evaluated organic acid blend improve broiler performance.

Resumo em Inglês:

ABSTRACT An experiment was conducted to evaluate the addition of the oil resins ofsucupira (Pterodon emarginatus Vog.) and copaiba (Copaifera langsdorffii) to broiler diets on chicken meat composition, quality, and lipid peroxidation. 350 one-d-old broiler chicks were submitted to seven treatments, consisting of the diets supplemented with copaiba (COP) or sucupira (SUC) resin oils at three different concentrations (500, 900, and 1300 ppm) plus a negative control diet (CONT). At 37 days of age, 10 birds per treatment were selected according to the average weight of the experimental unit and slaughtered to collect breast and thigh meat, which was stored at 4°C for 24 hours to evaluate pH, color (L*, a*, b*), cooking weight loss (CWL), and shear force (SF). Raw meat was vacuum packed and stored frozen until lipid peroxidation analysis. Meat samples were pooled to prepare pre-cooked meatballs (30 ± 0.5g), stored under refrigeration (eight days), and analyzed every two days for TBARS concentration. Results were analyzed using the PROC GLM and MIXED procedures (SAS statistical software). Plant oils increased (p<0.05) breast meat humidity (HU) and crude protein (CP) levels and reduced (p<0.05) total lipid (TLC) and ash (AS) levels when compared with the CONT treatment. Plant oils increased (p<0.05) thigh meat HU when compared with the CONT. High COP dietary levels reduced (p<0.05) breast meat CWL, and increased (p<0.05) thigh meat L* values when compared to CONT, except for SUC500 and SUC900. The dietary inclusion of plant oil resins showed a pro-oxidant effect (p<0.01) on breast meat when compared with the CONT. Low SUC dietary supplementation levels significantly reduced (p<0.01) the concentration of secondary oxidation products in thigh meat.

Resumo em Inglês:

ABSTRACT Fermented cottonseed meal (FCSM) is widely used in poultry diets in China. This study was conducted to investigate the effect of FCSM on lipid-related gene expression in broilers. Initially, 180 broiler chickens (21-days-old, equal number of males and females) were randomly divided into three groups, with six pens per group and 10 birds per pen. The chickens in the control group were fed a diet containing unfermented cottonseed meal, and those in the treatment groups were fed with diets including either CSM fermented by Candida tropicalis (Ct group) or CSM fermented by Candida tropicalis plus Saccharomyces cerevisae (Ct-Sc group) until 64 days old. The results revealed that, compared with the control group (p<0.05), the mRNA expression of peroxisome proliferator-activated receptor alpha (PPAR-a) and lipoprotein lipase (LPL) were upregulated in the livers of Ct-Sc males. The expression of PPAR-a was also upregulated in the livers of Ct females. The expression levels of acetyl CoA carboxylase (ACC) and LPL in the liver of males and the expression of PPAR-a in the liver of females were significantly different between the Ct and Ct-Sc groups (p<0.05). However, gene expressions of fatty acid synthase (FAS) and liver fatty acid-binding protein (L-FABP) in the liver were not altered when the broilers were fed FCSM-supplemented diets (p>0.05). Likewise, the expressions of peroxisome proliferator-activated receptor gamma (PPAR-g) and LPL in the abdominal fat were not altered by the FCSM-supplemented diets (p>0.05). The results in this study indicate that CSM fermented by Candida tropicalis and Saccharomyces cerevisiaeeffectively regulated the genes involved in fatty acid b-oxidation and triglyceride hydrolysis in male broiler chickens. Furthermore, the effects of the FCSM-supplemented diets were significantly different between bird sexes and between yeast strains used in the fermentation process.

Resumo em Inglês:

ABSTRACT These experiments were performed to determine the chemical composition, coefficients of nutrient and energy metabolizability, amino acid composition, and cytotoxicity of different castor oil meals subjected to different detoxification processes and added to the diet of Japanese quails. In the trial, 180 46-d-old female Japanese quails were distributed according to a completely randomized design into five treatments and with replicates of six bird each. The treatments consisted of following detoxification methods of castor oil meal: Castor oil meal A (CMA) - recovery in alcohol at 80 °C for 20 minutes and drying at 80 °C; castor oil meal B (CMB) and C (CMC) - recovery in alcohol at 80 °C for 6 minutes, neutralization with 5% NaOH, and drying under direct sunlight sun for two days (CMB) or pelleted (CMC); castor oil meal D (CMD) - recovery in alcohol at 110 °C for 15 minutes and drying at 110 °C. Castor oil meal was added replacing 20% of the reference diet. There was slight chemical composition variation (1.21% in crude protein, 6% in dry matter, 2.2% in ether extract and 64 kcal/kg in gross energy) among the castor oil meals submitted to the different treatments. The castor oil meal submitted to treatment C showed the highest amino acid values. In the cytotoxicity test, treatment D presented lower ricin activity. Castor oil meals A, C, and D may be included in Japanese quail diets; however, castor oil meal D is recommended due to the simplicity its industrial process, its low toxicity, and metabolizability coefficients obtained.

Resumo em Inglês:

ABSTRACT The effects of the dietary inclusion of olive pulp (OP) and the supplementation of a commercial enzyme blend (ENZ) on the gastrointestinal tract (GIT) size, and immune and hematological parameters were evaluated. In total, 600 one-day-old Ross 308 male broiler chicks were divided into 6 treatments according to a completely randomized design, in a 2×2×2 factorial scheme, consisting of the dietary inclusion of two olive pulp levels (50 and 100 g/kg in diet), two pulp categories (processed and unprocessed), and the inclusion or not of an enzyme blend. On d 42, birds were euthanized and blood samples were collected, and lymphoid, hematologic, and GIT organs were measured. The inclusion of 100g/kg OP in the diets increased jejunum relative weight (J%) and jejunum length (p ≤ 0.05). Processed OP reduced jejunum weight and length, J%, and left cecum length, serum triglycerides and VLDL cholesterol levels (p ≤ 0.05). Enzyme supplementation did affect any of the studied parameters (p>0.05). The OP inclusion improved the GIT size, while processed OP reduced GIT measurements and serum lipid levels.

Resumo em Inglês:

ABSTRACT This study aimed at evaluating the replacement of inorganic copper, manganese, and zinc sources by organic sources in the diet of laying hens during the second laying cycle in trace mineral excretion, egg production, and eggshell quality. Two hundred and fifty 100-week-old Dekalb hens were distributed according to a completely randomized design into five treatments with five replicates of ten birds each. The control treatment consisted of a basal diet with all trace minerals in the inorganic form. The other treatments consisted of a basal diet with a mixture of the minerals copper, manganese, and zinc in the organic form with concentrations of 100%, 90%, 80%, and 70% of the levels of inclusion of inorganic mineral sources in the control treatment. Trace mineral excretion was determined in five layers per treatment by the method of total excreta collection. Excreta trace mineral contents were determined by atomic absorption spectrophotometry. Egg production and eggshell quality were determined by the mass of the eggs and the egg specific gravity, respectively. For all trace minerals examined, the dietary supplementation with organic sources reduced trace mineral excretion compared with the control group, even at 70% inclusion level, without compromising egg production or eggshell quality. The replacement of the inorganic trace mineral sources by organics source effectively reduced the excretion of copper, manganese, and zinc by laying hens in the second laying cycle.

Resumo em Inglês:

ABSTRACT This study aimed at evaluating four dietary L-Glutamine (L-Gln) or L-Gln plus L-Glutamate (L-Glu) supplementation programs on the performance, breast yield, and uniformity of broilers. A total of 2,112 one-d-old male Cobb 500(r) broilers were distributed according to a randomized block design in a 2 × 4 factorial arrangement (L-Gln or L-Gln plus L-Glu × 4 supplementation programs), totaling eight treatments with 12 replicates of 22 broilers each. The supplementation programs consisted of the dietary inclusion or not of 0.4% of L-Gln or L-Gln plus L-Glu for four different periods: 0 days (negative control), 9d, 21d, and 42d. Feed intake (FI, g), body weight gain (BWG, g), feed conversion ratio (FCR, kg/kg), coefficient of variation of body weight (CV, %), body weight uniformity (UNIF, %), breast weight (BW, g), breast yield (BY, %), coefficient of variation of breast weight (CVB), breast uniformity (UNIFB), coefficient of variation of breast yield (CVBY), and breast yield uniformity (UNIFBY) were evaluated. Birds fed the diets treatments supplemented with L-Gln or L-Gln plus L-Glu for 9d presented 3% higher BWG (p<0.05) compared with the controls. The L-Gln or L-Gln plus L-Glu supplementation until broilers were 21 days old resulted in 14, 10, 16, and 12% improvements (p<0.05) in CV, UNIF, CVBY, UNIFBY, respectively. The supplementation of 0.4% L-Gln (L-Gln 99%) or L-Gln plus L-Glu (minimum 95%) to pre-starter and starter broiler diets is recommended to improve body weight gain and uniformity.

Resumo em Inglês:

ABSTRACT A total of 350-one-day old chicks were placed in 70 cages, with 14 cages per treatment. The following five treatment diets were fed for 14 days: T1 = non-supplemented, control diet (CONT); T2 = diet with antimicrobial growth promoter (AGP); T3 = diet with a probiotic (PROB); T4 = diet with a prebiotic(PREB), and T5 = diet with the probiotic and the prebiotic (SYM). The growth experiment was carried out from 1 to 14 days of age. Feed and water were provided ad libitum and birds were maintained at 24-h light schedule. Diets were formulated to contain 3000 kcalME/kg and 21.5% crude protein, and the test materials were added on top. The cumulative results of1 to 14 days of age revealed that broiler fed the AGP and PREB diets presented the highest BWG (305.5 and 297.3 g, respectively), while those fed the CONT diet had the lowest BWG (273.2 g) (p<0.05). On the other hand, the best FCR was obtained in broilers AGP and PROB (1.296 and 1.299 g:g, respectively), while chicks on the CONT and SYM diet had the worst FCR (1.423 and 1.372 g:g, respectively) (p<0.01). The results showed broilers fed the non-supplemented diet consistently presented poor performance. It was concluded that PROB or PREB can serve as alternatives to antibiotic in broiler starter feeds, with no performance impairment.