Response of Laying Hens to Repletion and Depletion in Dietary Balanced Protein.

This study was carried out to investigate the response of laying hens given a repletion or depletion in dietary balanced protein (BP) during the laying phase period. At the beginning of the rearing period (eight w-old), four-hundred pullets were equally distributed and received one of two experimental feeds: 1-Low BP (L) and 2-High BP (H). For the laying period (19 to 102 w-old), four feeding programs were designed based on the same treatments for rearing phases (LL, HH, LH, HL), where subsequent letters indicate the feed received during the rearing and laying period, respectively. The performance responses, egg quality, and body composition were periodically collected during the laying period. Two-way ANOVA repeated measures analysis was applied to evaluate the data. Nonlinear regression models with groups were used to compare treatments in the laying phase, with the treatments being the group evaluated. All performance traits were somehow influenced by the level of BP in the feed (p < 0.050). Hens subjected to the repletion treatment (LH) demonstrated a recovery in performance after 38 w-old. The opposite result was observed for hens on the depletion treatment (HL). All egg components were affected by dietary BP (p < 0.050). Laying hens demonstrated a limited capacity to overcome a reduction in dietary BP during production, but they were able to recover from a previous deficient feed once they were given an opportunity to do so.

Dynamics of Growth and Egg Traits in Three Dietary Balanced Protein Scenarios Applied for Laying Hens.

The objective of this study was to evaluate laying hens from 8 to 102 weeks old, regarding their changes in performance, body composition, and egg components produced in three scenarios of nutrition. Three treatments designed to contain different levels of balanced protein (BP) were randomly assigned to the experimental units, performing ten replicates per treatment with 20 birds each. A standard feed was formulated to meet hen requirements and the ideal ratio between essential amino acids. Then, two experimental feeds were formulated to contain 20% above or below the dietary BP used in the standard feed. The responses evaluated were cumulated feed intake (g), daily feed intake (g/day), body weight (g), body composition (g of protein, fat, and ash), hen-housed egg production (%/hen-housed), egg production (%), egg weight (g), egg mass (g), and egg components (percentages of yolk, albumen, and eggshell). The dietary BP influenced the body composition, egg production, egg weight, and egg mass of white laying hens. The increase in dietary BP was related to an increase in body contents and egg weight, whereas hens consuming the low dietary balanced protein presented a lower body weight, leaner, and produced smaller eggs.

Supplementation of minerals and vitamins in broiler diets: effect on performance and bone quality / Suplementação de minerais e vitaminas em dietas de frangos de corte: efeito sobre desempenho e qualidade óssea

Differences in growth rate and carcass composition of broilers may require higher levels of vitamins and minerals with higher bioavailability. The aim of this trial was to supplement commercial diets for broilers with optimized levels of vitamins and with different mineral sources to assess the effect on performance, carcass yield and bone quality. A total of 1,800 Cobb Slow male broiler chicks were distributed into a 2 x 2 factorial completely randomized design (vitamin programs - optimized and commercial versus mineral sources - inorganic [sulfates] and carbo-amino-phospho-chelate, CAPC). The vitamin D3 metabolite, 25 (OH) D3, was included in the optimized vitamin premix. Birds and feed leftovers were weekly weighed. Data was subjected to statistical analysis using the GLM procedure of SAS software. Supplementing diets with a combination of optimized vitamin programs and CAPC as mineral source resulted in better feed conversion at 42 days of age (P<0.05). Supplementation with CAPC minerals resulted in a lower red index (*a) (P<0.05) in the adjacent thigh muscles and drumstick bones of broilers when thawed and roasted, indicating less bone porosity. The inclusion rates of mineral sources with higher bioavailability can be reduced, decreasing the negative impact of mineral excretion and the polluting effect on the environment.

As diferenças na velocidade de crescimento e na composição de carcaça dos frangos podem exigir níveis mais altos de vitaminas e de minerais com maior biodisponibilidade. O objetivo deste trabalho foi suplementar dietas comerciais para frangos de corte com níveis otimizados de vitaminas e com diferentes fontes minerais para avaliar o efeito sobre o desempenho produtivo, rendimento de carcaça e qualidade óssea. Foram utilizados 1800 pintos de corte machos da linhagem Cobb Slow, divididos em um delineamento inteiramente casualizado em esquema fatorial 2 x 2 (programas vitamínicos - otimizado e comercial Vs fontes de minerais - inorgânicos (sulfatos) e carbo-amino-phospo-chelate, CAPC). No premix vitamínico otimizado foi incluído o metabólito da vitamina D3, 25(OH)D3. As aves e as sobras de ração foram pesadas semanalmente. A análise estatística dos dados foi realizada pelo procedimento GLM do software SAS. A suplementação de dietas com associação de programas vitamínicos otimizados e fonte mineral CAPC resultou em melhor conversão alimentar aos 42 dias de idade (P<0,05). A suplementação com minerais CAPC resultou em menor índice de vermelho (*a) (P<0,05) na musculatura adjacente aos ossos das coxas e sobrecoxas dos frangos de corte quando descongeladas e assadas, indicando menor porosidade óssea. Fontes mais biodisponíveis de minerais permitem reduzir a sua inclusão nas dietas e diminuem o impacto negativo da excreção de minerais e o efeito poluidor sobre o meio ambiente.

Suplementação de minerais e vitaminas em dietas de frangos de corte: efeito sobre desempenho e qualidade óssea / Supplementation of minerals and vitamins in broiler diets: effect on performance and bone quality

As diferenças na velocidade de crescimento e na composição de carcaça dos frangos podem exigir níveis mais altos de vitaminas e de minerais com maior biodisponibilidade. O objetivo deste trabalho foi suplementar dietas comerciais para frangos de corte com níveis otimizados de vitaminas e com diferentes fontes minerais para avaliar o efeito sobre o desempenho produtivo, rendimento de carcaça e qualidade óssea. Foram utilizados 1800 pintos de corte machos da linhagem Cobb Slow, divididos em um delineamento inteiramente casualizado em esquema fatorial 2 x 2 (programas vitamínicos - otimizado e comercial Vs fontes de minerais - inorgânicos (sulfatos) e carbo-amino-phospo-chelate, CAPC). No premix vitamínico otimizado foi incluído o metabólito da vitamina D3, 25(OH)D3. As aves e as sobras de ração foram pesadas semanalmente. A análise estatística dos dados foi realizada pelo procedimento GLM do software SAS. A suplementação de dietas com associação de programas vitamínicos otimizados e fonte mineral CAPC resultou em melhor conversão alimentar aos 42 dias de idade (P<0,05). A suplementação com minerais CAPC resultou em menor índice de vermelho (*a) (P<0,05) na musculatura adjacente aos ossos das coxas e sobrecoxas dos frangos de corte quando descongeladas e assadas, indicando menor porosidade óssea. Fontes mais biodisponíveis de minerais permitem reduzir a sua inclusão nas dietas e diminuem o impacto negativo da excreção de minerais e o efeito poluidor sobre o meio ambiente.

Differences in growth rate and carcass composition of broilers may require higher levels of vitamins and minerals with higher bioavailability. The aim of this trial was to supplement commercial diets for broilers with optimized levels of vitamins and with different mineral sources to assess the effect on performance, carcass yield and bone quality. A total of 1,800 Cobb Slow male broiler chicks were distributed into a 2 x 2 factorial completely randomized design (vitamin programs - optimized and commercial versus mineral sources - inorganic [sulfates] and carbo-amino-phospho-chelate, CAPC). The vitamin D3 metabolite, 25 (OH) D3, was included in the optimized vitamin premix. Birds and feed leftovers were weekly weighed. Data was subjected to statistical analysis using the GLM procedure of SAS software. Supplementing diets with a combination of optimized vitamin programs and CAPC as mineral source resulted in better feed conversion at 42 days of age (P<0.05). Supplementation with CAPC minerals resulted in a lower red index (*a) (P<0.05) in the adjacent thigh muscles and drumstick bones of broilers when thawed and roasted, indicating less bone porosity. The inclusion rates of mineral sources with higher bioavailability can be reduced, decreasing the negative impact of mineral excretion and the polluting effect on the environment.

Bacillus subtilis and Bacillus licheniformis reduce faecal protein catabolites concentration and odour in dogs.

BACKGROUND: Direct-fed microbials (DFM), such as Bacillus subtilis and Bacillus licheniformis, may improve gut functionality of the host by favouring non-pathogenic bacteria and reducing the formation of putrefactive compounds. The aim of this study was to assess the nutrient digestibility, faecal characteristics and intestinal-fermentation products in dogs fed diets with Bacillus subtilis and Bacillus licheniformis. Sixteen dogs were randomly divided into two groups. Every eight dogs were fed with the control diet or the diet with the addition of 62.5 g of DFM (B. subtilis and B. licheniformis)/ton. Diets were provided throughout a 20-day adaptation period, followed by 5 days of total faecal collection. Nutrient digestibility and the metabolisable energy of the diets, plus the dogs' faecal characteristics and intestinal fermentation products were assessed. RESULTS: There were no differences in nutrient digestibility (P > 0.05). However, DFM supplementation improved faecal score and resulted in less fetid faeces (P < 0.001). DFM inclusion reduced (P < 0.05) the biogenic amines concentration: putrescine, spermidine and cadaverine, besides the concentration of phenols and quinoline. CONCLUSIONS: The use of B. subtillis and B. licheniformis as DFM reduce the concentration of nitrogen fermentation products in faeces and faecal odour, but the digestibility of nutrients is not altered in dogs.

Different trace mineral sources and recommendations in the performance and quality of eggs from Dekalb White layers

This work aimed to evaluate the performance and egg quality of lightweight laying hens supplemented with a high biological value mineral, carbo-amino-phospho-chelates (CAPC), compared with inorganic minerals (sulfates), at different recommended values. A total of 320 Dekalb White hens, between 53 and 77 weeks of age, were distributed in a completely randomized design into two treatments, 10 replicates of 16 birds each. The treatments consisted of a reference diet formulated according to breed manual recommendations, in which one group was supplemented with a trace mineral source, CAPC (Cu, 8.6; Fe, 43.7; Mn, 56.4; Se, 0.34; and Zn, 43.7 mg/kg) and the other with a sulfate source, using the levels recommended in the breed manual (Cu, 8; Fe, 60; Mn, 70; Se, 0.25; and Zn, 60 mg/kg). There was no effect of trace mineral supplementation on egg production variables, feed conversion ratio by mass or by dozen eggs, and eggs per housed bird. However, there was an increase in feed intake and weight and mass of eggs when birds fed diet supplemented with CAPC. Regarding egg quality, CAPC supplementation increased the albumen weight and percentage, shell weight, thickness, and strength, and Haugh unit. The eggs from birds fed CAPC supplementation showed higher levels of iron and zinc when compared with eggs from birds fed the sulfate source diet. Better quality rates were observed in variables related to shelf life for the group that received CAPC. Trace mineral sources and recommendations in the diets of high genetic potential laying hens need to be reassessed and allow us to conclude that totally replacing the sulfate for different recommendations of CAPC in laying hen diets helps to improve quality characteristics as well as the nutritional value of eggs.(AU)

Efeito de diferentes densidades populacionais e do sexo sobre o desempenho e uniformidade em frangos de corte / Effect of different stocking rates and sex on the performance and uniformity of broilers

O experimento teve a finalidade de comparar o desempenho e uniformidade de frangos de corte separados por sexo e criados em diferentes densidades populacionais. Para tanto foram utilizados 1800 pintos de 01 dia da linhagem Ross, distribuídos em 36 parcelas experimentais (Boxes), de acordo com um delineamento experimental tipo blocos ao acaso, obedecendo um modelo fatorial 3x2 com 3 sexos (Machos, Fêmeas e Misto) e duas densidades populacionais (10 e 15 aves/m²), com 6 repetições por tratamento, sendo 40 ou 60 aves por repetição. As rações experimentais foram formuladas à base de milho e farelo de soja. Foram efetuadas medidas semanais de consumo de ração e peso dos animais, e ao final de 45 dias os animais foram abatidos. Ao final do período experimental, os resultados mostraram que os maiores valores de peso, consumo, Conversão Alimentar e Ganho Médio Diário foram verificados na menor taxa de lotação empregada, havendo significância estatística (p<0,05) para os itens: consumo (todos os períodos) e Conversão Alimentar (1-21 e 22-45 dias). Todavia, o incremento na taxa de lotação apresentou maiores viabilidade e uniformidade.Quanto aos sexos empregados, foram observados melhores valores para os machos, havendo diferença significativa (p<0,05) para peso corporal (21 e 45 dias), consumo (22-45 e 1-45 dias), Conversão Alimentar (1-45 dias) e Ganho Médio Diário.

This experiment was developed to compare the performance and uniformity of broilers chickens as related to sex and different stocking rates. 1800 one day Ross breed chicks were distributed in 36 boxes, on a completely randomized block design, 3x2 factorial, with 3 sex (male, female and mixed) and 2 stocking (10 and 15 birds/m²). There were six replications per treatment, with 40 or 60 birds per replication. The experimental ration was formulated with corn and soy bean meal. The results were taken weekly, and after 45 days the animals were slaughtered. The results showed an increase in weight, consumption food, food conversion and daily weight gain in the smaller stocking, with statistical significance (p<0,05) for: food consumption (all period) and food conversion (1-21 and 22-45 days). However, the increase in stocking showed better values in viability and uniformity. With regard the sex, better values were seen for males, with statistical significance (p<0,05) for weight (21 and 45 days), food consumption(22-45 and 1-45 days), food conversion (1-45 days) and daily weight gain.

Efeito de diferentes densidades populacionais e do sexo sobre o desempenho e uniformidade em frangos de corte / Effect of different stocking rates and sex on the performance and uniformity of broilers

O experimento teve a finalidade de comparar o desempenho e uniformidade de frangos de corte separados por sexo e criados em diferentes densidades populacionais. Para tanto foram utilizados 1800 pintos de 01 dia da linhagem Ross, distribuídos em 36 parcelas experimentais (Boxes), de acordo com um delineamento experimental tipo blocos ao acaso, obedecendo um modelo fatorial 3x2 com 3 sexos (Machos, Fêmeas e Misto) e duas densidades populacionais (10 e 15 aves/m²), com 6 repetições por tratamento, sendo 40 ou 60 aves por repetição. As rações experimentais foram formuladas à base de milho e farelo de soja. Foram efetuadas medidas semanais de consumo de ração e peso dos animais, e ao final de 45 dias os animais foram abatidos. Ao final do período experimental, os resultados mostraram que os maiores valores de peso, consumo, Conversão Alimentar e Ganho Médio Diário foram verificados na menor taxa de lotação empregada, havendo significância estatística (p<0,05) para os itens: consumo (todos os períodos) e Conversão Alimentar (1-21 e 22-45 dias). Todavia, o incremento na taxa de lotação apresentou maiores viabilidade e uniformidade.Quanto aos sexos empregados, foram observados melhores valores para os machos, havendo diferença significativa (p<0,05) para peso corporal (21 e 45 dias), consumo (22-45 e 1-45 dias), Conversão Alimentar (1-45 dias) e Ganho Médio Diário.(AU)

This experiment was developed to compare the performance and uniformity of broilers chickens as related to sex and different stocking rates. 1800 one day Ross breed chicks were distributed in 36 boxes, on a completely randomized block design, 3x2 factorial, with 3 sex (male, female and mixed) and 2 stocking (10 and 15 birds/m²). There were six replications per treatment, with 40 or 60 birds per replication. The experimental ration was formulated with corn and soy bean meal. The results were taken weekly, and after 45 days the animals were slaughtered. The results showed an increase in weight, consumption food, food conversion and daily weight gain in the smaller stocking, with statistical significance (p<0,05) for: food consumption (all period) and food conversion (1-21 and 22-45 days). However, the increase in stocking showed better values in viability and uniformity. With regard the sex, better values were seen for males, with statistical significance (p<0,05) for weight (21 and 45 days), food consumption(22-45 and 1-45 days), food conversion (1-45 days) and daily weight gain.(AU)