This study aimed to assess the effects of starting creep feeding at different ages on performance, behaviour, haematological, and biochemical parameters in piglets. A total of 138 piglets (1.34 ± 0.25 kg, n = 13 sows), weaned at 21 d-old, were assigned to treatments using a completely randomized design. The litter was divided into two groups: seven litters (n = 80 piglets) were subjected to creep feeding on the fifth day of age (creep 5) and five litters (n = 58 piglets), on the tenth day of age (creep 10). Piglets were weighed at birth, weaning, and after the first week in the nursery. Piglet behaviour was evaluated daily for 15 min until day 20. Blood was collected on day 13, at weaning, and at the end of the first week in the nursery. There was no difference in body weight in the suckling phase, but piglets fed Creep 5 showed greater body weight gain in the first nursery week. The Creep 5 group had lower feed leftovers during the five days of evaluation of feed intake. There were no differences in haematological parameters and amylase concentration; however, the piglets spent more time lying down, sucking, and massaging the udder. On day 8, the piglets in the Creep 5 group showed a higher frequency of exploratory behaviour. In conclusion, piglets fed Creep 5 had optimal performance after weaning and improved feed intake capacity by displaying more exploratory behaviour than Creep 10. Creep management did not alter haematological and biochemical parameters.

This study aimed to assess the effects of starting creep feeding at different ages on performance, behaviour, haematological, and biochemical parameters in piglets. A total of 138 piglets (1.34 ± 0.25 kg, n = 13 sows), weaned at 21 d-old, were assigned to treatments using a completely randomized design. The litter was divided into two groups: seven litters (n = 80 piglets) were subjected to creep feeding on the fifth day of age (creep 5) and five litters (n = 58 piglets), on the tenth day of age (creep 10). Piglets were weighed at birth, weaning, and after the first week in the nursery. Piglet behaviour was evaluated daily for 15 min until day 20. Blood was collected on day 13, at weaning, and at the end of the first week in the nursery. There was no difference in body weight in the suckling phase, but piglets fed Creep 5 showed greater body weight gain in the first nursery week. The Creep 5 group had lower feed leftovers during the five days of evaluation of feed intake. There were no differences in haematological parameters and amylase concentration; however, the piglets spent more time lying down, sucking, and massaging the udder. On day 8, the piglets in the Creep 5 group showed a higher frequency of exploratory behaviour. In conclusion, piglets fed Creep 5 had optimal performance after weaning and improved feed intake capacity by displaying more exploratory behaviour than Creep 10. Creep management did not alter haematological and biochemical parameters.

The objective of this study was to evaluate the effects of golden mussel flour (GMSF) contaminated with increasing rates of cadmium (Cd) as a replacement for limestone as a Ca source, in broiler chicken feed from 14 to 42 days of age. A total of 60 animals were assigned to four treatments (inclusion rates of Cd: 6.94, 14.55, 22.40, and 30.00 mg Cd kg-1) with five replications in a completely randomized design. At 42 d, blood samples were collected to evaluate serum concentrations of aspartate amino transferase (AST), alanine amino transferase (ALT), gamma glutamyl transferase (GGT), total bilirubin, Ca, P, and Cd. After slaughter, tissues were collected to evaluate Cd concentration in bone parameters. Growth performance of broiler chickens and Cd content in the breast meat were not affected by the inclusion rates of Cd in the GMSF. However, there was an effect of Cd in GMSF on the concentration of Cd in the skin, liver, bones, feathers, and serum; ALT; and total bilirubin. Bone flexibility had a quadratic response to increasing inclusion rates of GMSF; serum Ca concentration increased linearly and there was no effect on serum P concentration. Concentrations of Cd in GMSF above 20 mg kg-1 caused high Cd contamination in broiler tissues. Therefore, it was concluded that Cd concentrations above 6.94 mg kg-i in broiler diets caused high Cd concentrations in meat and organs that are above those permitted for human consumption.

The objective of this study was to evaluate the use of clinoptilolite zeolite to enhance performance in broiler chickens. Nine hundred male broiler chickens were distributed in a completely randomized design to four treatments with nine repetitions. Treatments included clinoptilolite zeolite in the diet at 0, 2500, 5000 and 10000 grams/ton. Inclusion of zeolite caused a linear increase in ammonia released by the litter after 21 days, with greater effects at 42 days. The digestibility coefficient for dry matter increased, whereas the digestibility coefficients for crude protein, gross energy, and ash were not affected. Zeolite affected the digestibility of dry matter, gross energy and ash, with digestible gross energy and digestible ash showing a quadratic effect. The same effect was shown in the percentage of abdominal fat and the relative weight of the pancreas. Zeolite did not change the performance, serum levels and quality of the litter at 42 days old. It improved the percentage of digestible nutrients and increased pancreas weight.

The dietary inclusion of hydroethanolic extract of guavira seed or peel was evaluated on broiler performance, intestinal morphometry, carcass yield, and meat quality. A total of 1,680 male chicks, one day old, were distributed in a 2x5+2 factorial design (hydroethanolic extract of guavira seed (HEGS) or hydroethanolic extract of guavira peel (HEGP); 100; 200; 300; 400 and 500 mg/kg of inclusion and a positive control (PC) with antibiotics and negative control (NC) without growth promoter), with seven replicates and 20 birds each. A better feed conversion ratio (FCR) was observed from days 1-7 and days 1-21 on the PC diet than on the NC diet. FCR from 1-7d of broilers on PC was better than those on HEGS or HEGP, and this better FCR was maintained until 21 d for the HEGS treatment. The HEGP diet showed lower average feed intake and better FCR for the total period compared to NC diets. Higher carcass yield and a higher L15 value for breast meat was observed in the HEGP group compared to HEGS. Broilers fed the PC diet showed a higher a* value 15 min and 24 h postmortem, higher water retention capacity in breast meat compared to birds fed HEGS, and a higher value of a* 24 h postmortem than those receiving NC. The inclusion of 100 to 500 mg/kg of HEGP or HEGS did not improve performance, intestinal morphometry, and carcass characteristics when compared to the performance-enhancing antibiotic. However, the HEGP diet provided better performance of broilers than the non-use of growth promoter additives in the diet.

This article assessed the performance, carcass yield, and meat quality of finishing broilers fed increasing levels of hydroethanolic extract of guavira fruit peel (HEGP) were assessed. A total of 480, three-weeks-old male broilers were randomly allocated to dietary levels of HEGP (0, 100, 200, 300, 400, and 500 mg/kg), with five replicates and 16 birds each. There was a quadratic effect of HEGP inclusion on weight gain (Wg) and feed conversion ratio (FCR), with the greatest WG and FCR being calculated at levels of 314 and 219 mg/kg HEGP, respectively. Broilers fed diets containing the extract had better performance than those fed an extract-free diet. There was no effect of extract inclusion on carcass yield and cuts. There was a quadratic effect of HEGP inclusion on a* (redness) of thigh meat at 15 min post-mortem, and on waterholding capacity (WHC), with the lowest and highest values being calculated at 270 mg/kg and 263 mg/kg HEGP, respectively. There was a quadratic influence of HEGP inclusion on the malonaldehyde content at 30-day storage, with highest value being calculated at 218 mg/kg HEGP. Dietary inclusion of 219 mg/kg of HEGP resulted in better FCR for broilers in the finishing phase but without improvement in meat quality.

The objective was to evaluate the effect of diets containing various levels of phytate and phytase on broilers from 1 to 42 days old. The treatments consisted of a combination of diets containing high (HP), medium (MP) and low (LP) phytate with positive control diet (PC) and a negative control diet (NC) that was similar to the PC in energy and protein but with less calcium and phosphorus. Three additional diets, based on the NC were supplemented with 500, 1000, or 1500 FTU kg-1 of phytase. Broilers that received the NC diet exhibited the lowest weight gain (WG), whereas those supplemented with 1000 FTU kg-1 obtained 2.84% higher WG compared with PC. Broilers that received NC had the lowest breaking strength and dry matter. Birds fed HP diets that received NC and NC + 500 FTU kg-1 had a higher concentration of serum Ca and P than birds fed LP diets. Broilers fed the NC and NC + 500 and 1000 FTU kg-1 had lower tibia Ca levels compared with birds fed the PC. Broilers fed HP diets had higher tibia Ca content than MP. Phytase supplementation had a positive response in diets with reduced Ca and P. Based on regression analysis the optimum inclusion of phytase to improve broiler performance parameters was calculated as 952 FTU kg-1.

RESUMO Os valores energéticos da glicerina bruta (GB) foram determinados para frangos de corte em diferentes idades, por meio da utilização do método proposto por Matterson e de regressões polinomiais. Foram realizados dois ensaios: de 11 a 21 dias e de 31 a 41 dias de idade das aves; em ambos, as aves foram distribuídas em um delineamento experimental inteiramente ao acaso, com uma ração referência (RR), sem GB, e três rações testes com substituição de 5%, 10% e 15% da RR por GB. Foram calculados os valores de energia metabolizável pelo método de Matterson, sendo os valores de energia metabolizável aparente (EMA) utilizados na análise de regressão polinomial. Os valores médios da EMA corrigida pelo balanço de nitrogênio (EMAn), o coeficiente de metabolizabilidade da EB (CMAEB) e o corrigido para o balanço de nitrogênio (CMAEBn) da GB, na matéria natural, para a fase de 11 a 21 dias, pelo método de Matterson, foram de 10,08 MJ kg-1, 10,04 MJ kg-1, 67,06% e 66,74%, respectivamente. A inclusão de GB apresentou um efeito linear crescente para os CMAEB e os CMAEBn. Na fase de 31 a 41 dias, foram de 10,38 MJ kg-1, 10,27 MJ kg-1, 69,02% e 62,24%, respectivamente. Por meio das equações de regressões polinomiais, o valor de EMAn estimada foi de 10,49 MJ kg-1 e 10,18 MJ kg-1, respectivamente. Os valores de EMAn da GB para as idades 11 a 21 e 31 a 41 dias foram de 10,04 MJ kg-1 e 10,26 MJ kg-1, respectivamente. De acordo com as equações propostas por Matterson e com o método de Adeola, os valores de EMAn foram 10,49 e 10,20 MJ kg-1 para cada fase.

ABSTRACT The energetic values of crude glycerin (CG) were determined for broilers at different ages using the method proposed by Matterson and by polynomial regressions. Two trials were performed with broilers from 11 to 21 and from 31 to 41 days of age. The birds were distributed in a completely randomized experimental design with a reference ration (RR), without CG, and three ration tests with replacement of 5%, 10%, and 15% of RR by CG. The metabolizable energy values were calculated by the Matterson method, and the apparent metabolizable energy (AME) values were used in polynomial regression analysis. The mean values of AME, apparent corrected for nitrogen balance (AMEn), metabolizable coefficient of gross energy (CAMEB), and corrected for nitrogen balance (CAMEBn) of CG, for the phase from 11 to 21 days by the Matterson method were 10.08 MJ kg-1, 10.04 MJ kg-1, 67.06%, and 66.74%, respectively. The inclusion of CG presented an increasing linear effect for CAMEB and CAMEBn in this period. From 31 to 41 days, these values were 10.38 MJ kg-1, 10.27 MJ kg-1, 69.02%, and 62.24%, respectively. The predicted AMEn value through the polynomial regression equations was 10.49 MJ kg-1 and 10.18 MJ kg-1, respectively. According to the equations proposed by Matterson, the crude glycerin EMAn values for broilers from 11 to 21 and 31 to 41 days of age were 10.04 MJ kg-1 and 10.26 MJ kg-1, respectively. According to Adeola's method the AMEn values were 10.49 and 10.20 MJ kg-1 for each phase.

RESUMO Foram determinados os valores energéticos e a composição bromatológica do resíduo seco de fecularia (RSF) para frangos de corte, na fase de crescimento, utilizando ou não enzimas carboidrases. Os tratamentos foram distribuídos em esquema fatorial 2x4 + ração referência, sendo uma RR sem adição de RSF e quatro tratamentos experimentais com 10%, 20%, 30% e 40% de inclusão do RSF e a suplementação ou não com carboidrases. A composição química encontrada para o RSF, na MN, foi de 89,86% de matéria seca, 0,98% de proteína bruta, 3519kcal kg-1 de energia bruta, 0,19% de extrato etéreo, 27% de fibra em detergente neutro, 19,5% de fibra em detergente ácido, 0,33% de cálcio, 0,43% de fósforo, 0,46% de potássio e 0,12% de magnésio. O uso de carboidrases proporcionou um aumento de 173 e 213kcal kg-1 nos valores de EMA e EMAn, respectivamente, resultando em 1828kcal kg-1 EMA e 1840kcal kg-1 EMAn. Concluiu-se que os maiores níveis de EMA e EMAn foram encontrados para o nível de inclusão médio do RSF de 35% e que a suplementação enzimática pode promover aumento desses parâmetros em até 12% em dietas para frangos de corte na fase de crescimento.

ABSTRACT The energetic values and the bromatological composition of the dry residue of cassava (DRC) were determined for growing broilers with or without carbohydrase enzymes. The treatments were distributed in a 2x4 + reference diet factorial scheme, with one RD without addition of DRC and four experimental treatments with 10, 20, 30 and 40% inclusion levels of RSF and supplementation or not with carbohydrases. The chemical composition found for DRC in natural matter was 89.86% dry matter, 0.98% crude protein, 3519kcal kg-1 gross energy, 0.19% ether extract, 27% neutral detergent fiber, 19.5% of acid detergent fiber, 0.33% of calcium, 0.43% of phosphorus, 0.46% of potassium and 0.12% of magnesium. The use of carbohydrase resulted in an increase of 173 and 213kcal kg-1 in EMA and EMAn values, respectively, resulting in 1828kcal kg-1 EMA and 1840kcal kg-1 EMAn. It was concluded that the highest levels of AME and AMEn were found for the mean inclusion level of the DRC of 35% and that enzymatic supplementation may promote the increase of these parameters by up to 12% in broiler diets in the growth phase.

The objective was to evaluate increasing levels of dried brewers' grains (DBG) in feed for broiler chickens from 1 to 21 days old and their effect on performance, blood parameters, intestinal morphometry, carcass characteristics and meat quality. The design was completely randomized with six treatments, which consisted of various levels of DBG inclusion, namely 0 (no inclusion), 20, 40, 60, 80, and 100 g/kg with seven replications and 17 animals per experimental unit, totalling 714 male broilers. Performance parameters, blood biochemical profile, morphology of the intestinal epithelium (duodenum), and carcass yield and composition were evaluated. Feed intake was not changed by DBG inclusion levels. Nor were weight gain and feed conversion ratio. Serum cholesterol levels were not influenced, and there were no effects on triglyceride, uric acid and creatinine levels. Enzyme aspartate aminotransferase showed a quadratic effect, as did alanine aminotransferase, with higher values at 79.5 and 63.9 g/kg DBG inclusion, respectively. No changes in carcass yield and relative organ weight were observed. The composition of the carcass in ether extract showed a quadratic effect, as fat deposition rate, with lowest values at 62.8 and 62.4 g/kg of DBG inclusion levels, respectively. Crude protein levels in carcass reduced linearly, as did fat deposition rate. The parameters of intestinal morphology and meat quality were not changed. Dried brewers' grains can be included in broiler diet from 1 to 21 days at levels up to 100 g/kg without influencing the metabolic parameters and broiler performance.

The objective of this study was to evaluate the effects of various geometric mean diameters (GMDs) of particles of corn, pelleted soybean meal and a corn-soy mixture in the proportion of 70% and 30%, respectively, on the nutritional value of the feeds. The study evaluated energy consumption, the contents of apparent metabolizable energy (AME) and AME corrected for nitrogen balance (AMEn) and the metabolizability coefficients for broiler chickens at various ages. A total of 540 Cobb 500 male broilers were housed in metabolic cages (experimental units). Trials were performed separately with each feed. A completely randomized design was used with four treatments, namely corn with 573, 636, 851, and 1012 μm GMDs; pelleted soybean meal with 538, 550, 665, and 741 μm GMDs; and the corn-soy mixture with 627, 658, 893, and 1040 μm GMDs. Birds were evaluated on days 1 - 10, 11 - 20, 21 - 30, and 31 - 40. Larger GMDs resulted in lower energy consumption. From 1 to 10 days, birds consumed less metabolizable energy than older birds. Birds fed corn from days 1 to 10 had higher metabolizable energy (P <0.05) with increasing GMD up to 1042 μm. However, the results varied, depending on the feed and its combinations. The use of coarse particles could reduce the costs of grinding, and would have few effects on the metabolizable energy of broiler chickens.

O experimento foi conduzido com o objetivo de avaliar o desempenho e a morfologia intestinal de frangos de corte na fase de crescimento, com e sem adição de nucleotídeos na dieta, em diferentes níveis proteicos. Foram utilizados 868 pintos de cortes machos de 21 dias de idade, da linhagem Cobb, submetidos a um delineamento inteiramente casualizado. As dietas foram compostas por dois controles, de alta e baixa proteína bruta, com 18,86% e 16,80% respectivamente, com a exigência de 1,062% de lisina digestível. Tendo como base a dieta controle de baixa proteína foram traçados mais cinco tratamentos com adição de 0,5 kg de nucleotídeos/ton de ração, e diferentes níveis de lisina digestível: 1,262%, 1,162%, 1,062%, 0962% e 0,862%, com quatro repetições cada. O consumo alimentar (g) diminuiu linearmente (P≤0,05) no período de 20 a 27, de 20 a 35 e de 20 a 42 dias de idade, em que aumentando os níveis de lisina digestível na dieta, observou-se diminuição no consumo de ração. A conversão alimentar teve efeito quadrático (P≤0,05) para as aves do período de 20 a 27, de 20 a 35 e de 20 a 42 dias de idade, diminuindo à medida que os níveis de lisina digestível aumentaram, atingindo o mínimo com 1,119, 1,187 e 1,132% de lisina digestível, respectivamente. A dieta com 1,062% de lisina digestível não diferiu (P>0.05) da dieta controle com alta proteína, para altura das vilosidades e profundidade de cripta, no duodeno, ilustrando então efeito benéfico do uso de nucleotídeos em dietas com baixa proteína bruta.

The experiment was conducted to evaluate the performance and intestinal morphology of growing broilers, with and without addition of nucleotides in the diet at different protein levels. A total of 868 21-day-old male Cobb broiler chicks were used in a completely randomized design. The diets were: control with high crude protein (18.86%) and low crude protein (16.80%), both without nucleotides, meeting the requirement of 1.062% digestible lysine; and five treatments with the addition of 0.5 kg of nucleotides/ton of feed, with different levels of digestible lysine (1.262%, 1.162%, 1.062%, 0962% and 0.862%), all formulated based on the low-protein diet (16.80%), with four replications each. Feed intake (g) decreased linearly (P≤0.05) in the period from 20 to 27, 20 to 35, and 20 to 42 days of age; feed intake decreased by increasing levels of lysine in the diet. Feed-to-gain ratio showed a quadratic effect (P≤0.05) for birds of the period from 20 to 27, 20 to 35 and 20 to 42 days of age, decreasing as levels of digestible lysine increased, with minimum levels reaching 1.119%, 1.187% and 1.132% digestible lysine, respectively. The diet with 1.062% of lysine did not differ (P>0.05) from the negative control for villus height and crypt depth in the duodenum.

Os efeitos da suplementação da vitamina D3 e de seus diferentes metabólitos foram avaliados na resposta imune e na morfometria intestinal de frangos de corte. Foram utilizados 952 frangos de corte de um dia de idade, distribuídos em um delineamento inteiramente casualizado, com quatro tratamentos, sete repetições e 34 aves por unidade experimental. Os tratamentos foram constituídos por quatros diferentes fontes de vitamina D3: colecalciferol (D3), 25-hidroxicolecalciferol (25(OH)D3), 1,25-dihidroxicolecalciferol (1,25(OH)2D3) e 1α-hidroxicolecalciferol (1α(OH)D3). As diferentes fontes foram incluídas na dieta, fornecendo 2000 e 1600 UI de vitamina D, nas fases pré-inicial, inicial e de crescimento, respectivamente. O peso relativo do intestino delgado diferiu entre os tratamentos aos 7, 21 e 42 dias e o peso relativo do fígado somente aos 42 dias de idade. Os demais órgãos e parâmetros imunológicos avaliados (peso dos órgãos linfóides, reação de hipersensibilidade cutânea basofílica, avaliação da atividade de macrófagos, dosagem de nitrito e perfil heterofilo: linfócito foram similares entre os animais alimentados com os diferentes metabólitos. Houve efeito (P<0,05) dos diferentes metabólitos da vitamina D3 sobre o comprimento dos vilos de jejuno e íleo aos sete dias, diferindo entre os animais alimentados com 1,25(OH)2D3 e 1α(OH)D3 para jejuno e 1,25(OH)2D3 e vitamina D3 para íleo (P<0,05). Para as demais fases não foi observado influência (P>0,05) dos tratamentos. Os parâmetros imunológicos não foram afetados pelos diferentes metabólitos de vitamina D. Os diferentes metabólitos de vitamina D afetaram positivamente a morfometria intestinal na altura de vilo na fase inicial, sendo os melhores resultados obtido pelos animais alimentados com 1,25(OH)2D3, contudo os parâmetros imunológicos foram similares entre os metabólitos estudados.

The aim of this experiment was to evaluate the effect of different vitamin D metabolites on immune response and intestine morphometry of broiler chickens. We used 952 1-day-old chicks, male Cobb, distributed into a completely randomized design with four treatments, seven replications and 34 birds each. There were evaluated four different metabolites of vitamin D: D3, 25(OH)D3, 1,25(OH)2D3 and 1α(OH)D3, providing 2000 and 1600 IU/kg feed of vitamin D in initial and growth period, respectively. The different metabolites of vitamin D did not affect the relative weight of the organs except for the weight of the intestine and liver at 21 and 42 days. There was a significant effect (P<0.05) of the different metabolites of D3 vitamin on the villi length of jejunum and ileum at 7 days, between animals fed with 1,25(OH)2D3 and 1α(OH)D3 to the jejunum and 1,25(OH)2D3 and vitamin D3 to the ileum (P<0.05). There were no differences (P>0.05) for weight of lymphoid organs, cutaneous basophil hypersensitivity reaction, macrophage activity assessment, measurement of nitric oxide and heterophil profile: lymphocyte. The different sources of vitamin D affect the intestine morphometrics on the villi length in the initial phase, but the effect was not observed in other phases. The immunological parameters were not affected by metabolites of vitamin D.