Effects of feeding diets with zinc-l-selenomethionine on growth performance of broilers subjected to cyclic heat stress.

Limited information exists on the use of zinc-l-selenomethionine (Zn-L-SeMet) in broiler diets and its effects on the growth performance, body temperature, mortality rates, blood profile, and gene expression, especially when animals are reared under cyclic heat stress conditions. This study aimed to investigate the impact of Zn-L-SeMet in broiler diets from 1 to 42 days of age reared under cyclic heat stress and its effects on growth performance, cloacal temperatures, mortality rate, blood parameters, and insulin-like growth factor 1 (IGF-1) and growth hormone receptor (GHR) gene expression in the breast muscle. A total of 1000 male Cobb 500® broiler chicks were randomly assigned to five treatments: 0, 0.15, 0.23, 0.47, and 1.30 mg/kg of Zn-L-SeMet. Each treatment consisted of 10 replicates with 20 birds each. No statistically significant differences in growth performance were observed from 1 to 21 days of age (P > 0.05). However, from 1 to 42 days, feed intake (FI) and feed conversion ratio (FCR) decreased linearly (P < 0.05). Cloacal temperatures showed no significant effects (P > 0.05), while overall mortality rate exhibited a quadratic response (P < 0.05), with the optimal inclusion level predicted to reduce broiler mortality at 0.71 mg/kg. Triglyceride (TRG) levels increased with 0.97 mg/kg (P < 0.05), and gama-glutamil transferase (GGT) levels decreased with the inclusion of 1.19 mg/kg (P < 0.05). No significant effects on IGF-1 and GHR gene expression were found (P > 0.05). In conclusion, the inclusion of 1.30 mg/kg of Zn-L-SeMet in diets of heat-stressed broilers improved growth performance from 1 to 42 days of age. An inclusion of 0.71 mg/kg reduced mortality rate, while 0.97 mg and 1.19 mg increased and reduced TRG and GGT levels, respectively.

Influence of dietary corn distillers' dried grains with solubles on nutrient digestibility, growth performance, and carcass traits in rabbits.

Two experiments were performed to evaluate the digestibility and growth performance of New Zealand White rabbits fed corn distillers' dried grains with solubles (DDGS). For the digestibility trial, 20 rabbits were housed in metabolic cages. The animals were distributed in two treatments, T1 (control diet without inclusion of DDGS) and T2 (control diet + 300 g kg-1 DDGS). For the growth performance trial, 100 rabbits (50 males and 50 females) were assigned in a factorial design 2 × 5 (2 gender × 5 inclusions of DDGS) and five replicates. The treatments were composed of diets with inclusions of 0, 60, 120, 180, and 240 g kg-1 of DDGS. The rabbits were housed at 35 days old, and the experiment lasted 35 days. The DDGS showed high digestibility for protein (74.10%) and lipids (81.51%) and a high content of digestible energy (2979 kcal kg-1). In the second trial, growth performance and carcass yield and organ relative weights were evaluated. There were no interactions between gender and DDGS inclusions (P > 0.05). A linear decrease was observed for feed intake (FI) for the period from days 35 to 50 (FI, P = 0.001) and FI and FCR from days 35 to 70 (FI, P = 0.004; FCR, P = 0.001) with the increasing levels of DDGS. Rabbits supplemented with 240 g kg-1 had lower (P < 0.05) whole carcass yield (WCY) and carcass without head yield compared with the control rabbits. DDGS is highly digestible in rabbits, and when supplemented up to 240 g kg-1 in diets, it improved FCR but reduced FI and WCY.

Performance, metabolism, and meat quality of broilers fed dry brewery residue.

A study was conducted to assess the chemical composition and apparent metabolizable energy (AME), nitrogen-corrected AME (AMEn), and their respective coefficients of dry brewery residue (DBR) for broilers. A second study was conducted to evaluate the increasing inclusions of DBR in broiler diets and its effects on growth performance, carcass traits, blood metabolites, and meat quality. In the first trial (metabolism assay), a total of 250 male broilers were assigned to 5 diets (0, 100, 200, 300, and 400 g DBR/kg) composed by 5 replications with 10 animals per cage in a completely randomized design in the period from days 11 to 21. There was an increasing linear effect for AME, AMEn, metabolizable coefficient of gross energy (MCGE), and MCGE corrected for N (MCGEn). In the second experiment, a total of 840 one-day-old male broiler chickens were assigned to 6 treatments (0, 20, 40, 60, 80, and 100 g DBR/kg) with 7 replications and 20 animals per pen, from days 0 to 42. Growth performance was determined at days 21 and 42. There was an increasing linear effect for weight gain in the period from days 0 to 21 and for feed intake from days 0 to 42. A linear decreasing effect was observed at day 21 for cholesterol and quadratic effect for uric acid (UA), aspartate aminotransferase, and albumin. At day 42, there was a quadratic effect for UA and creatinine. At day 21, an increasing linear effect was observed for protein deposition rate. In conclusion, the inclusion of DBR up to 100 g/kg improved WG in the starter phase and did not negatively affect the productive parameters of broilers from days 0 to 42.

Effects of vitamin A on carcass and meat quality of broilers.

This study evaluated the level and length of time of vitamin A supplementation and its effects on carcass and cuts yield, meat quality, and myopathies in 42-day-old broilers. A total of 1,920 birds were divided into 6 groups, and each group received a different level of vitamin A: 0; 6,000; 16,000; 26,000; 36,000 and 46,000 IU/ kg. From d 1 to 21, the treatments were distributed among 16 replicates with 20 birds. From the 22nd d on, 8 repetitions remained with the initial treatment and the others received diets with no vitamin A supplementation. Twelve birds were slaughtered per treatment to evaluate carcass and cuts yield, shear force, cooking loss, water holding capacity, and the presence of substances reactive to thiobarbituric acid. The remaining birds were slaughtered and evaluated in loco for Wooden Breast (WB) and White Striping (WS). Wings weight was affected by vitamin A levels. The duration of the vitamin A supplementation process had effects on the weight of breast, legs with a dorsal portion, and meat color in the yellow intensity (b*). Incidence of WB had higher scores in birds supplemented until 42 d of age. WS showed a quadratic response and a lower response with supplementation of 29,700 IU/ kg. Even for WS, a higher occurrence of the normal score was found in birds supplemented until 21 d of age. Minimal quadratic responses were obtained for normal, moderate, and severe scores, in supplementations of 29,301; 29,959, and 29,827 IU/ kg, respectively. WB had lower occurrence rates in birds supplemented until 21 d of age. Consequently, the severe score was more frequent when supplementation was provided until 42 d of age. The level of vitamin A and the length of time during which this supplementation was provided had influence on cuts yield, meat color and the incidence of WB and WS of the 42-day-old birds.

Carcass characteristics and meat quality of slow-growing broilers fed diets containing dry residue of cassava, with or without the addition of carbohydrases.

This study evaluated the carcass and portion yield and meat quality of slow-growing broilers fed diets with increasing levels of dry residue of cassava (DRC), with or without the addition of carbohydrases. A total of 1100 Label Rouge male broilers were distributed in a completely randomized 2 × 5 factorial design (with or without the addition of carbohydrases and five levels of DRC [0, 2.5, 5.0, 7.5, and 10.0%]), with five replicates and 22 birds per experimental unit. No interaction (P > 0.05) was observed between enzyme addition and DRC levels for the carcass yield, portion yield (back, legs, wings, breast), or abdominal fat variables. There was an interaction (P < 0.05) between the addition of enzyme and DRC on breast pH 15 min post-mortem and the a* intensity of the breast in a colorimetry test. There was a quadratic effect on b* intensity independent of adding enzymes, with the lowest intensity predicted at 8.89% DRC. Regarding feet color, increasing DRC supplementation (independent of enzyme supplementation) led to an increase and decrease in L* and b* intensity, respectively (P < 0.05). Moreover, there was a quadratic effect on a* intensity, with a lower level of intensity predicted at 6.93% DRC (P < 0.05), regardless of the inclusion of enzymes. The inclusion of up to 10% dry residue of cassava in slow-growing broiler diets does not affect carcass and portion yield or the qualitative characteristics of the meat but does reduce the color of the breast meat and feet.

Supplementation of pig diets in the growth and termination phases with different calcium sources.

The aim of this study was to evaluate the effect of supplementation of pig diets in the growth and termination phases with different calcium sources. In experiment I, 36 whole males were distributed in randomized blocks in six groups, with six replications. A basal diet was formulated to meet the animals' nutritional requirements except for calcium (0.09%), and the sources evaluated (calcitic limestone, monodicalcium phosphate, calcinated bone flour, and oyster flour) replaced the basal diet to provide 0.59% of total calcium. To determine the endogenous calcium, a diet containing low calcium (0.019%) was given simultaneously to another group of animals. Feces and urine were collected for determination the coefficients of apparent and true digestibility. In experiment II, 160 piglets were distributed in randomized blocks in four treatments, with five replications and four animals per experimental unit. Carcass and performance parameters, calcium concentration in bone and serum, and bone parameters were evaluated. The data were submitted to analysis of variance and factorial. The calcium source did not influence the digestibility coefficients determined by total collection (P > 0.05). The digestibility of Ca from oyster flour estimated by collection with an indicator was higher than that from the other sources (P < 0.05). Calcium sources did not interfere in the evaluated parameters (P > 0.05). The sources studied in this work can be used to supplement growing pigs' diets.

Sunflower cake with or without enzymatic complex for broiler chickens feeding.

OBJECTIVE: This study was to evaluate the sunflower cake and enzymatic complex fed to broilers from 22 to 42 d of age. METHODS: In a completely randomized design, a total of 850 birds were allotted in a 2×5 factorial scheme (with and without enzymatic complex) and five inclusion levels (0%, 5%, 10%, 15%, 20%) of sunflower cake. There were 5 replications and 17 birds in each experimental unit. Data from performance, carcass yield and intestinal morphology were evaluated. RESULTS: Feed intake, weight gain, final weight and feed:gain ratio linearly worsened as sunflower cake increased. For weight gain, final weight and feed:gain ratio, the birds whose diets contained levels of 15% and 20% of sunflower cake showed worse values (p<0.05) than the birds fed the control diet. When fed the enzymatic complex, birds improved (p<0.05) crypt depth and villus:crypt ratio in the jejunum. As inclusion levels of sunflower cake increased, villus depth and villus:crypt ratio in duodenum, jejunum and ileum linearly reduced and the crypt depth linearly increased. Carcass yield linearly reduced as sunflower cake increased. CONCLUSION: Based on performance, sunflower cake can be used up to 10% in broilers feeding from 21 to 42 days of age.

Performance of broiler chickens at pre starter and starter phases using diets with different metabolizable energy values of ingredients, at different ages / Desempenho de pintos de corte nas fases pré-inicial e inicial, utilizando dietas com diferentes valores de energia metabolizável dos ingredientes, em diferentes idades

ABSTRACT: The experiment was carried out to evaluate the performance of broilers in 1-7 and 8-21 days of age, using metabolizable energy values of corn, soybean meal and soybean oil previously determined for each phase in another metabolism trial. Two trails were conducted, divided into phases according to ages: pre-starter (1-7 days) and starter (8-21 days). At each trial were used 924 broiler chicken randomly distributed into 42 experimental units in a completely randomized design with six treatments and seven replications. Treatments consisted of five diets using the values of apparent metabolizable energy corrected for nitrogen balance of corn, soybean meal and soybean oil determined in different metabolism trials, and one diet with the metabolizable energy values of these same ingredients, published on the literature. At the end of each stage, the animals and feed leftover were weighted to determine feed intake, weight gain and feed conversion ratio. Diets with higher soybean oil inclusion, showed superior performance at different stages. At pre-starter only feed conversion ratio was significant (P<0.05). In the initial phase, there was a significant difference (P<0.05) for feed conversion ratio, daily and average weight gain.

RESUMO: O experimento foi realizado para avaliar o desempenho de frangos de corte nas idades de 1-7 e 8-21 dias de idade, utilizando valores de energia metabolizável do milho, farelo de soja e óleo de soja determinados anteriormente em outro ensaio de metabolismo. Dois estudos foram realizados, divididos em fases de acordo com as idades: pré-inicial (1-7 dias) e inicial (8-21 dias). Em cada estudo, foram utilizados 924 pintos de corte distribuídos aleatoriamente em 42 unidades experimentais, em um delineamento inteiramente casualizado consistindo de cinco dietas utilizando os valores de energia metabolizável aparente corrigida para o balanço de nitrogênio do milho, farelo de soja, e óleo de soja, determinados nos ensaios de metabolismo, e uma dieta com os valores de energia metabolizável dos mesmos alimentos publicados na literatura. No final de cada fase, os animais e as sobras de ração foram pesadas para determinar o consumo de alimento, ganho de peso e conversão alimentar. As dietas com maiores inclusões de óleo de soja mostraram desempenho superior nas diferentes idades. Na fase pré-inicial, apenas a conversão alimentar foi significativa. Na fase inicial, houve diferença significativa para a conversão alimentar e ganho de peso médio e diário.

Redução da proteína bruta em rações sobre os balanços metabólicos de suínos mantidos em diferentes condições térmicas / Reducing crude protein in diets on the metabolic balances for pigs kept in different thermal conditions

O objetivo deste trabalho foi avaliar a redução da proteína bruta em rações sobre o balanço de nitrogênio, pH urinário e parâmetros sanguíneos de suínos na fase inicial. O peso médio inicial dos animais foi de 18,5 ± 0,73kg. Foram realizados dois experimentos de digestibilidade, sendo um em condições de ambiente de estresse (28,77˚C) e outro conforto térmico (18,13˚C). Em ambos os experimentos os animais foram distribuídos em um delineamento experimental de blocos ao acaso com quatro níveis de proteína bruta (20,5;19,4; 18,3 e 17,2%) e quatro repetições, totalizando 16 unidades experimentais em cada experimento, sendo cada uma representada por um animal, totalizando 32 animais. A metodologia utilizada foi a coleta total de fezes, e a urina coletada e filtrada diariamente. Para avaliar os parâmetros sanguíneos, as amostras foram obtidas mediante punção na veia jugular. Os parâmetros avaliados foram nitrogênio ingerido, excretado nas fezes e na urina, absorvido, retido, retido/absorvido, excreção total, utilização líquida de proteína, pH da urina, colesterol, triglicerídeos, glicose, uréia e creatinina no plasma sanguíneo. Conclui-se que a redução do nível de proteína da dieta, de 20,5 a 17,2%; é uma alternativa eficiente para reduzir a quantidade de nitrogênio excretado pelos suínos em condição de estresse térmico. Para condição de conforto térmico os suínos apresentaram maiores concentrações de creatinina e colesterol plasmático.

The objective of this study was to evaluate the reduction of crude protein diets on nitrogen balance, urinarypH and blood parameters of starter pigs. The average initial weight of the animals was 18.5 ± 0.73 kg. Two digestibility experiments were conducted, one in environmental conditions of stress (28.77 ˚ C) and another in thermal comfort condition (18.13 ˚ C). In both experiments, the animals were distributed in randomized blockswith four decreasing levels of crude protein (20.5, 19.4, 18.3 and 17.2%) and four replications, totaling 16experimental units in each experiment, each represented by an animal, totaling 32 animals. The methodology used was the total collection of feces and urine was collected and filtered daily. To assess blood parameters, samples were obtained by jugular vein puncture. The parameters evaluated were ingested nitrogen, excreted in feces and urine, absorbed, retained, retained/absorbed, total excretion, net protein utilization, urine pH,cholesterol, triglycerides, glucose, urea and creatinine in blood plasma. It is concluded that reducing the levelof protein in the diet, 20.5 to 17.2%; is an efficient alternative to reduce the amount of nitrogen excreted bypigs in heat stress condition. In thermal comfort condition pigs showed higher concentration of creatinine and serum cholesterol.

Cassava starch factory residues in the diet of slow-growing broilers.

The objective of this study was to evaluate the effect of inclusion of dehydrated cassava starch residue (DCSR) on the performance, gastrointestinal tract characteristics and carcass traits of ISA Label JA57 slow-growing broilers. A total of 510 broilers at 21 were distributed in a randomized experimental design with 5 treatments (2, 4, 6, 8, and 10 % DCSR inclusion) and a control group, 5 replicates, and 17 birds per experimental unit. The DCSR inclusion from 21 to 49 days of age negatively influenced (P < 0.05) weight gain and feed intake and did not affect (P > 0.05) feed conversion in the broilers with increasing of DCSR inclusion. From 21 to 79 days, DCSR inclusion impaired (P < 0.05) weight gain, feed conversion, and poultry litter quality with increasing of DCSR inclusion. The level of blood triglycerides showed a quadratic response (P < 0.05) at 79 days of age with the highest value predicted to occur at 5.45 % of DCSR inclusion. DCSR levels affected (P < 0.05) the gastrointestinal organ characteristics, cecal content pH, and pigmentation of the shank, breast, and thigh meat of the birds but did not alter (P > 0.05) the other parameters of carcass quality and yield, cuts, and percentage of abdominal fat. In conclusion, DCSR inclusion levels above 2 % compromised broiler performance.

Correlação entre contagem de células somáticas, parâmetros microbiológicos e componentes do leite em amostras de leite in natura / Correlación entre contaje de células somáticas, parámetros microbiológicos y componentes de la leche en muestras de leche in natura / Correlation among somatic cells count, microbilogical parameters and milk components in samples of in natura milk

O objetivo deste trabalho foi avaliar a qualidade do leite cru refrigerado, tendo em vista os padrões estabelecidos pela Instrução Normativa nº 51; assim como verificar a correlação existente entre a contagem de células somáticas, componentes do leite e contagens bacterianas. Os resultados mostraram que das 72 amostras avaliadas, 91,66% para aeróbios mesófilos, foram consideradas acima dos padrões exigidos pela legislação. Todas as amostras estavam contaminadas com coliformes a 35°C e coliformes termotolerantes. As contagens de mesófilos proteolíticos e de CCS também foram consideradas altas. No teste de lactofermentação, 85% das amostras apresentaram formas visuais não desejáveis; no teste de resistência térmica apenas 20% mantiveram-se estáveis. Correlações significativas foram obtidas entre CCS e os componentes do leite (proteína e lactose) e CCS e contagens microbiológicas.

This study aimed to evaluate the quality of cooled raw milk regarding the standards established by Law nº 51, as well as to verify the correlation existing among the somatic cell count (SCC), milk components and bacterial counts. The results of 72 analyzed samples pointed out that 91.66 % was out of the standards for mesophilic aerobes. All the samples were contaminated with coliforms at 35ºC and thermotolerant coliforms. The counts of proteolytic mesophiles and SCC were considered high. In the lactofermentation test, 85% of the samples showed visual undesirable forms, and in the thermal resistance test, only 20% kept stable. Significant correlations were obtained between somatic cell count and milk composition (protein and lactose), and between SCC and bacterial count.

El objetivo de este estudio ha sido evaluar la calidad de la leche cruda refrigerado, teniendo en cuenta los estándares establecidos por la Instrucción Normativa nº 51; así como verificar la correlación existente entre el contaje de células somáticas, componentes de la leche y contajes bacterianas. Los resultados señalaron que de las 72 muestras evaluadas, 91,66% para aerobios mesófilos, han sido consideradas arriba de los estándares exigidos por la legislación. Todas las muestras estaban contaminadas con coliformes a 35ºC y coliformes termo tolerantes. Los contajes de mesófilos proteolíticos y de CCS también fueron considerados altos. En el test de lacto fermentación, 85% de las muestras presentaron formas visuales no deseables; en el test de resistencia térmica solamente 20% se mantuvieron estables. Correlaciones significativas se ha obtenido entre CCS y los componentes de la leche (proteína y lactosa) y CCS y contajes microbiológicas.

Desempenho, microbiota intestinal e peso de órgãos de leitões na fase inicial recebendo rações com simbiótico e probiotico / Performance, intestinal microorganisms and organs weight of piglets in the initial phase receiving diets with simbiotic and probiotic

Neste Trabalho, objetivou-se avaliar o efeito da suplementação de dietas contendo probiótico e simbiótico sobre o desempenho de leitões dos 21 aos 49 dias, microbiota intestinal e peso dos órgãos. Foram utilizados 120 leitões mestiços desmamados aos 21 dias de idade, distribuídos em um delineamento de blocos casualizados, com três tratamentos (antibiótico, probiótico e simbiótico) e cinco repetições, sendo a unidade experimental representada pela baia, onde foram alojados oito leitões. No período de 21 a 35 dias de idade, não se observou diferença (P>0,05) no desempenho. No período de 36 até os 49 dias, pode-se observar maior ganho diário de peso (P<0,01) para o tratamento contendo antibiótico. Foi observada uma maior contagem de bactérias lácticas (P<0,05) no conteúdo do cólon, aos 35 dias de idade para o tratamento contendo probiótico. Os pesos relativos dos órgãos não foram influenciados (P>0,05) pelos tratamentos. O uso de probiótico e simbiótico nas rações foi efetivo para leitões dos 21 aos 35 dias de idade para as variáveis de desempenho e contagem de coliformes no íleo e cólon, e dos 36 aos 49 dias de idade o uso de antibiótico foi melhor em relação as variáveis de desempenho.

The objective of this study was to evaluate the effect of diets containing probiotic and simbiotic on the performance of piglets from 21 to 49 days, intestinal microorganisms and weight of organs. In this study there were used 120 crossbred piglets, weaned at 21 days of age, alloted in randomized blocks design, with three treatments (antibiotic, probiotic and simbiotic) and five replicates, being the experimental unit represented by the pen, where eight piglets were hosted. In the period from 21 to 35 days of age no difference was observed (P>0.05) for the performance results. In the period from 36 to 49 days could be observed a higher daily weight gain (P<0.01) for the antibiotic treatment. A higher count of lactic bacteria was observed (P<0.05) in the colon content, in piglets with 35 days of age, for the probiotic treatment. The relative organs weight was not influenced (P>0.05) by the treatments. The use of probiotic and simbiotic in the diets was effective for piglets from 21 to 35 days of age for performance and coliform count in the ileum and large gut, and from 36 to 49 days of age the use of antibiotic in the diet was better for the performance parameters.

Determinação e predição de valores energéticos de silagens de grãos úmidos de milho para suínos / Determination and prediction of energetic values of the high moisture corn grain silages for swine

Conduziu-se este trabalho, com os objetivos de avaliar a composição química e os valores energéticos de diferentes silagens de grãos úmidos de milho (SGUM) para suínos, e ajustar equações de predição para a energia digestível (ED) e metabolizável (EM) com base na composição química. Os tratamentos consistiram de oito diferentes silagens de grãos úmidos de milho, que substituíram em 30,0 por cento a ração referência. Foram realizadas as análises de MS, PB, EE, FB, FDA, FDN, Ca e P das silagens em estudo. Na determinação dos valores energéticos, foram utilizados 36 suínos, distribuídos em delineamento experimental de blocos ao acaso com quatro repetições. Os valores de ED e EM das silagens de grão úmido de milho variaram de 3494 a 3701 kcal/kg MS e 3392 a 3613 kcal/kg MS, respectivamente. Não se obteve um bom ajustamento das equações para predizer os valores de ED e EM da SGUM, apresentando baixos coeficientes de determinação, sendo que o extrato etéreo apresentou uma correlação positiva e a fibra bruta uma correlação negativa para os valores energéticos estudados.

The objectives of this study were to evaluate the chemical composition and energetic values of diferent high moisture corn grain silages (HMCGS) for swine, and to adjust prediction equations for digestible (DE) and metabolizable (ME) energy based on the chemical composition. The treatments consisted of eight diferent high moisture corn grain silages that substitued 30.0 percent of the basal diet. The analysis of DM, CP, EE, ADF, NDF, Ca and P were performed for the refered silages. To determine the energetic values 36 swines were used, alloted in a randomized blocks design with four replicates. The values of DE and ME of the HMCGS varied from 3494 to 3701 kcal/kg of DM and from 3392 to 3613 kcal/kg of DM, respectively. The equations adjusted to predict the DE and ME values of the HMCGS did not show a good adjustment, showing low determination coefficients, and the fat content showed a positive relation and the CF a negative one, for the energetic values studied.