Correlações entre as temperaturas da superfície corpórea e retal e os pesos médios de frangos de corte

Body temperature is one of the indicators of broilers’ susceptibility to thermal stress, which can compromise performance. This study aimed to evaluate correlations between both the surface and rectal temperatures, besides the average weight of broilers assessed in different ages. Temperatures of broilers’ back, breast, and rectum were evaluated, besides the average weight of broilers at 7, 14, 21, and 35 days old. One hundred birds were assessed for each evaluation age, and the variables were submitted to Pearson’s correlation analyses. The rectal temperature had a correlation with the breast one when the birds were evaluated at 7 and 14 days old. The average weight correlated only with rectal and breast temperatures at 14 and 21 days old, respectively. The correlations between the temperatures were weak or insignificant in most of the studied ages. Therefore, the skin temperature is not a suitable parameter for measuring broilers’ temperature compared to the rectal one, so the use of infrared thermometer did not prove to be a useful strategy to estimate the internal temperature of broilers.A temperatura corporal é um dos indicadores de suscetibilidade dos frangos de corte ao estresse térmico, o que pode comprometer o desempenho. Este estudo teve como objetivo avaliar as correlações entre as temperaturas superficial e retal, além do peso médio de frangos de corte avaliados em diferentes idades. Foram avaliadas as temperaturas do dorso, peito e reto das aves, além do peso médio das aves aos 7, 14, 21 e 35 dias de idade. Cem aves foram avaliadas para cada idade de avaliação, e as variáveis ​​foram submetidas à análise de correlação de Pearson. A temperatura retal apresentou correlação com a do peito quando as aves foram avaliadas aos 7 e 14 dias de idade. O peso médio correlacionou-se apenas com as temperaturas retal e do peito aos 14 e 21 dias de idade, respectivamente. As correlações entre as temperaturas foram fracas ou insignificantes na maioria das idades estudadas. Portanto, a temperatura da pele não é um parâmetro adequado para medir a temperatura de frangos de corte em comparação com a retal, de modo que o uso de termômetro infravermelho não se mostrou uma estratégia útil para estimar a temperatura interna de frangos de corte

Requirement for digestible lysine in Nile tilapias (Oreochromis niloticus) with live weight between 500 and 600 g

The present study was carried out with the objective of determining the requirements for digestible lysine in Nile tilapia during the 500 to 600 g live weight stage. Isocaloric and isonitrogenous diets were tested with increasing amounts of digestible lysine. L-lysine HCl (78%) were used to replace glutamic acid at increasing levels, resulting in treatments of 9.3, 12.3, 15.3, 18.3 and 21.3 g kg-1 of digestible lysine. Three hundred Nile tilapias with an average weight of 519 ± 27.23 g were used and distributed among 25 tanks. The physical and chemical parameters of the water were pH, dissolved oxygen, salinity, conductivity and temperature. The mortality rate was registered daily. Two slaughters were performed at 28 and 50 days after the beginning of the experiment. It was estimated that an amount of 13.1 g kg-1 of digestible lysine was ideal for obtaining higher WG. Fish slaughtered after 50 days, the digestible lysine requirements were determined to be 14.5 g kg-1 for the lowest carcass humidity and 14.6 g kg-1 for the greatest carcass ethereal extract. Nile tilapias with live weight between 500 and 600 grams require 13.1 g kg-1 of digestible lysine in the diet for greater WG (90.53 g) and better FCR (2.55)

Adição da macroalga Kappaphycus alvarezii em rações de frangos de corte na fase inicial

An experiment was conducted to evaluate the nutrient digestibility, zootechnical performance, and bone quality parameters of broilers fed a diet containing increasing levels of the macroalgae Kappaphycus alvarezii from one to 21 days of age. A total of 150 Cobb 500® broilers were distributed in a completely randomized design with five treatments, six replications, and five birds per replicate. The total excreta collection method was applied from the 15th and 20th day for the metabolism trial. The following bone quality parameters were assessed: the Seedor index, bone strength, and bone ashes. Dry ground macroalgae were added to the feed in the levels 0%, 0.5%, 1.0%, 1.5% and 2.0%; replacing the inert kaolin. Incorporation of Kappaphycus alvarezii did not influence performance parameters, bone quality parameters, or the coefficients of retention for bone ash and phosphorus. As for feed digestibility, decreases (p<0.05) were observed in apparent metabolizable energy and the coefficients of digestibility for dry matter, crude protein, and crude energy with the inclusion of algae. The algae Kappaphycus alvarezii shows potential as an additive in broiler feed, but a possible decrease in digestibility deserves consideration.Foi realizado um experimento para avaliar a digestibilidade de nutrientes, o desempenho zootécnico e parâmetros de qualidade óssea de frangos de corte alimentados, de um a 21 dias de idade, com rações contendo níveis crescentes da macroalga Kappaphycus alvarezii. O total de 150 frangos da linhagem Cobb 500® foram distribuídos em um delineamento experimental inteiramente casualizado, com cinco tratamentos, seis repetições e cinco aves por repetição. O ensaio de metabolismo utilizado foi o de coleta total de excretas, do 15º ao 20º dia. Os parâmetros ósseos avaliados foram o índice de Seedor, resistência a quebra e cinzas ósseas. A macroalga seca e moída foi adicionada às rações de frango de corte nos valores de 0%, 0,5%, 1,0%, 1,5% e 2,0%; em substituição ao inerte caulim. A adição de Kappaphycus alvarezii não influenciou os parâmetros de desempenho, os parâmetros de qualidade óssea e os coeficientes de retenção de cinzas e do fósforo. Na avaliação da digestibilidade das rações foram observadas reduções (p<0,05) na energia metabolizável aparente e nos coeficientes de digestibilidade da matéria seca, da proteína bruta e da energia bruta com a inclusão da alga. A alga Kappaphycus alvarezii apresenta potencial como aditivo nas rações de frangos de corte, mas deve ser considerada a possível diminuição da digestibilidade da dieta

Metabolizable energy and amino acid digestibility of soybean cake subjected to different dry extrusion temperatures for broilers

ABSTRACT Two experiments were conducted to evaluate the apparent metabolizable energy (AME), nitrogen-corrected apparent metabolizable energy (AMEn), and standardized ileal amino acid digestibility coefficient (SIDC) of extruded soybean cake (ESC) at four different extrusion temperatures: 90, 100, 110, and 120 °C. In experiment 1, 300 male broilers were randomly distributed into four treatments (600 g kg−1 reference diet + 400 g kg−1 of SBC at different extrusion temperatures) + reference diet, with six replicates of 10 birds. A metabolic assay using the total excreta collection method was performed from 14 to 23 days to determine AME and AMEn. Quadractic effect of the extrusion temperature was observed, with the maximum AMEn value estimated as 3424.99 kcal kg−1 for 105.58 °C. In experiment 2, 300 male broilers were randomly distributed into four treatments (453 g kg−1 protein free diet + 547 g kg−1 SBC at different extrusion temperatures) + protein free diet, with six replicates of 10 birds. Experimental diets were offered from 16 to 21 days, and at 21days, birds were sacrificed by cervical dislocation for collection of the ileal digesta to determine the SIDC of ESC. The best SIDC values for lysine (0.824%), methionine (0.908%), and cysteine (0.741%) were estimated at 117.72, 114.40, and 107.37 °C, respectively. The other amino acids evaluated showed a linear response, with better SIDC values with increasing extrusion temperatures. The extrusion temperatures affect metabolizable energy and amino acid digestibility of soybean cake for broilers, being important the standardization of extrusion temperature to maximize the nutritional value of soybean cake used in broiler diets

QUALIDADE ÓSSEA, EXCREÇÃO MINERAL E DIGESTIBILIDADE DA MATÉRIA SECA DE GALINHAS ALIMENTADAS COM CAULIM NO FINAL DO CICLO PRODUTIVO

O caulim adsorve toxinas e patógenos no trato gastrointestinal permitindo maior digestão e absorção de nutrientes, podendo propiciar melhor qualidade óssea de poedeiras na fase final de produção, mas adsorção de minerais, redução da digestibilidade da ração, também podem ser observados, dependendo do nível de inclusão da argila. Portanto o objetivo deste estudo é verificar a inclusão de caulim na ração de galinhas poedeiras semipesadas no final do ciclo produtivo e sua influência sobre a digestibilidade aparente da matéria seca, retenção e excreção mineral e qualidade óssea. Foram alojadas 144 galinhas em delineamento inteiramente casualizado, em seis tratamentos: controle (sem a inclusão do aditivo); e inclusão de 1, 2, 3, 4 e 5% de caulim na dieta. Às 85 semanas de idade das aves foram mensuradas a digestibilidade aparente da matéria seca da ração (Digap), a excreção e retenção de matéria mineral, e a excreção de cálcio e fósforo, para qualidade óssea foram mensurados o índice Seedor e a matéria mineral e resistência a quebra da tíbia. Após análise de variância, os dados foram submetidos à analise de regressão ao nível de significância de 5%. A Digap e a excreção de matéria mineral pioraram (P0,05) na excreção de cálcio e fósforo. O índice de seedor aumentou de maneira linear (P0,05). A inclusão de caulim favoreceu a retenção de minerais e a qualidade óssea em galinhas poedeiras no final do ciclo produtivo, não promovendo alteração na retenção do cálcio e do fósforo e reduziu a digestibilidade da ração

Standardized ileal phosphorus digestibility of meat and bone meal and poultry byproduct meal for broilers

Two experiments were conducted using direct method to determine the standardized ileal phosphorus (P) digestibility coefficient (SIPDC) of meat and bone meal (MBM) and poultry byproduct meal (PBM) for broilers. In the first experiment, three MBM from different batches were evaluated, with four treatments (MBMI, MBMII, MBMIII, and a P-free diet) and nine replicates of seven birds each, totaling 252 birds distributed across a completely randomized design. The P-free diet was used to determine endogenous P losses. Titanium dioxide (5 g kg−1) was used as an indigestible indicator. In the second experiment, three PBM from different batches were evaluated, with 189 birds distributed over three treatments (PBMI, PBMII, and PBMIII) and nine replicates of seven birds each. These two experiments were conducted when birds were 19-22 days old. The birds were euthanized to collect the ileal content. Using the P-free diet, endogenous P losses were determined at 94.9 mg kg−1 dry matter intake. Standardized ileal P digestibility of MBMI (0.65) and MBMIII (0.69) was higher compared with MBMII (0.49). The SIPDC determined for three PBM sources were similar and 0.96, 0.96, and 0.93 for PBMI, PBMII, and PBMIII, respectively. The present study demonstrates that P in MBM is not as available as it is believed and that the variability between batches should be considered by nutritionists, while PBM can be considered an excellent P source to broiler die

Effects of xylanase and probiotic supplementation on broiler chicken diets

The objective of the present study was to evaluate the effects of xylanase and probiotic supplementation on the performance, carcass characteristics, intestinal pH, intestinal viscosity, and ileal microbiota of broiler chickens fed diets containing wheat bran. The study animals were kept in metal cages, and the study was performed using a completely randomized design, with four treatments, six birds per treatment, and six replicates. The four treatments included a control group, a probiotic-supplemented group, a xylanase-supplemented group, and a group that received both xylanase and probiotic supplementation. The diets of all four groups contained wheat bran (50 and 30 g/kg for the starter and grower phases, respectively) and phytase, and at 10 d after hatching, the experimental birds were challenged orally with Eimeria sp commercial vaccine. During the initial phase, supplementation with xylanase, probiotics, or their combination yielded greater weight gains than the control diet; however, considering the period from 10-35 d, the chickens receiving xylanase + probiotic and the diet without the additives showed lower weight gain (2.746 and 2.600 kg, respectively). All the supplemented diets reduced cecum viscosity, and supplementation with probiotic showed a significantly lower pH (6.11). The ileal microbiota was also influenced by xylanase and probiotic supplementation, modulating the frequencies of the genera Lactobacillus and Clostridium. The positive effects of supplementation with xylanase or probiotics alone were similar to those of co-supplementation, and no associative effect was observe

Digestible lysine for broiler chickens with lower genetic potential grown on free-range system

ABSTRACT Determining the actual lysine requirement is crucial as it is an essential amino acid and plays animportant role in the metabolism of broilers. In addition, it is the second limiting amino acid for broilers fed with rations formulated basedon corn and soybean meal. The aim of this study was to determine the digestible lysine requirement for male broilers with lower genetic potential for growth in a semi-confined system as well as to evaluate the effects of different values of digestible lysine on performance and carcass characteristics. A total of 300 broiler chickensfrom a commercial lineage EMBRAPA 041 were used with an average initial weight of 987 g. The broilers were distributed into 20 experimental units in a completely randomized design with five treatments (0.586; 0.746; 0.906; 1.066, and 1.226% digestible lysine), four replicates and 15 broilers per experimental unit.In both periods, there were linear effect of digestible lysine values on the lysine intake and lysine utilization efficiency and quadratic effect on final body weight, weight gain and feed: gain ratio.There was a quadratic effect on the absolute weight of carcasses, breast, thigh + drumstick and income gizzard.For rearing of male broilers with lesser genetic growth potential reared in semi-confinement, rations with 1.040% and 1.103% digestible lysine can be recommended for maximum weight gain in periods from 35 to 70 and 35 to 84 days of age, respectively