The effects of supplementing canthaxanthin on productive and reproductive aspects of broiler breeders were examined in this study. In total, 360 female pullets and 36 roosters were placed in an open-sided house with 12 pens, each pen with an area of 7.0 m(2) (3.5 × 2.0 m). At 42 wk of age, the breeder hens and roosters were distributed into 2 experimental groups with similar BW and uniformity. From 46 to 66 wk of age, one group received 6 mg/kg of canthaxanthin supplemented in the diet and the other group received the diet without the addition of canthaxanthin (control diet). Body weight was measured every 28 d, the laying rate was calculated weekly, and mortality was evaluated at the end of the study. Twenty-one weekly incubations were performed to evaluate fertility and incubation responses. To evaluate the antioxidant effect of canthaxanthin at different storage times and during the incubation process, eggs from each treatment were subject to thiobarbituric reactive substances analysis. Body weight, mortality, and laying rate were not affected by the inclusion of canthaxanthin in the breeder's diets. An increase in hatchability of total and fertile eggs (P ≤ 0.0001 and P ≤ 0.0003, respectively) in breeders fed canthaxanthin during the experimental period was observed. Canthaxanthin also improved breeder fertility and reduced embryo mortality. This can be attributed to reductions in embryo mortality in the first 48 h of incubation and in the last wk of incubation. No differences were observed in BW and quality of the chicks. A reduction of thiobarbituric reactive substances was observed in yolks from stored hatching eggs produced by breeders fed diets plus canthaxanthin. The same effect was observed in yolks of eggs stored for 4 d and incubated for 7 d. The supplementation of broiler breeder diets with canthaxanthin improved the hatchability rate, fertility, and reduced the presence of thiobarbituric reactive substances in eggs.

1. The protective effect of a natural Brazilian calcium montmorillonite (CaMont) against aflatoxins was studied in broiler chickens. 2. A total of 1056-d-old Cobb male broilers were housed in experimental pens (22 chickens per pen) for 42 d. Three levels of CaMont (0, 2.5 and 5 g/kg) and two levels of aflatoxins (0 and 3 mg/kg) were assayed. Each treatment had 8 replicate pens of 22 broiler chickens each. 3. Of all the chickens tested in the experiment, the ones treated with aflatoxins were the most adversely affected. CaMont treatment at concentrations of 2.5 and 5 g/kg improved body weight of chickens at 42 d of age by 13.3% and 22.7%, increased daily feed intake by 9.7% and 24.7%, and improved the productive efficiency index of chickens by 53% and 66.5%, respectively. 4. Dietary CaMont positively affected parameters such as weight of liver, heart and gizzard; however, serum potassium concentration decreased by 15.3% compared with that of chickens given only the aflatoxin-contaminated diet. 5. CaMont did not cause adverse effects in chickens that did not receive aflatoxins. 6. CaMont at pH 8.5 partially reduced the toxic effects of aflatoxins in broilers when included at levels of 2.5 and 5 g/kg in the diet.

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Resumo -O objetivo deste trabalho foi avaliar o efeito de misturas de aditivos fitogênicos na dieta de frangos de corte, sobre seu desempenho zootécnico e rendimento de carcaça. Foram avaliados 660 pintos de sexo misto, entre 1 e 42 dias de idade, em delineamento inteiramente casualizado, com cinco tratamentos e seis repetições de 22 aves (11 machos e 11 fêmeas). Além do controle, foram avaliados tratamentos com antibiótico (10 ppm de virginiamicina) ou com misturas de aditivos fitogênicos: mistura A, 150 ppm de óleos essenciais de alecrim, cravo, gengibre e orégano; mistura B, 150 ppm de óleos essenciais de canela, sálvia, tomilho branco e óleo-resina de copaíba; e mistura A+B, 50% da mistura A e 50% da B. A mistura B proporcionou maior ganho de peso e melhor conversão alimentar das aves, no período de 36 a 42 dias de idade. No período total do experimento, o antibiótico e a mistura B proporcionaram maior ganho de peso das aves. O consumo de ração foi maior com o antibiótico do que com o controle. A mistura A+B e o tratamento controle proporcionaram maior rendimento de coxa+sobrecoxa e maior peso relativo do baço. As mistura B e A+B apresentam potencial como melhoradores de desempenho para frangos de corte.Termos para indexação: Gallus gallus, antibiótico melhorador de desempenho, extratos de plantas, óleos essenciais, óleo-resina de copaíba. Growth performance and carcass yield of broiler chicken feed diets with blends of phytogenic additivesAbstract -The objective of this work was to evaluate the effect of blending phytogenic additives in broiler chicken diets on their growth performance and carcass yield. Six hundred and sixty mixed-sex broiler chicks, from 1 to 42 days of age, were evaluated in a completely randomized design, with five treatments and six replicates of 22 chicks each (11 males and 11 females). Besides the control, treatments with antibiotic (10 ppm virginiamycin) or with blends of phytogenic additives were evaluated: blend A, 150 ppm of a mixture of essential oils from rosemary, clove, ginger, and oregano; blend B, 150 ppm of a mixture of essential oils from cinnamon, sage, white thyme, and copaiba oil-resin; and blend A+B, a mixture of 50% blend A and 50% blend B. Blend B provided the highest weight gain and better feed conversion rate at the period of 36 to 42 days of age. In the total experimental period, the antibiotic and blend B provided higher broiler weight gain. Feed intake was higher with the antibiotic than with the control. Blend A+B and the control treatment provided higher thigh+drumstick yield and higher relative weight of spleen. The blends B and A+B have potential as performance enhancers for broiler chicken.

RESUMO -Este trabalho foi realizado com o objetivo de avaliar o desempenho produtivo de matrizes de corte submetidas a dietas contendo aflatoxinas e adsorvente à base de glucomananos esterificados. Foram utilizados 300 fêmeas e 40 machos da linhagem Ross 308 alojados em 20 boxes experimentais na fase de 61 a 72 semanas de idade. Da 61 a à 68 a semana, as aves receberam dietas contendo três níveis de aflatoxina (0; 0,500; 0,750 mg/kg) em combinação ou não a adsorvente (0,10%) e, nas quatro últimas semanas, receberam dietas isentas de aflatoxina e adsorvente. As aves foram distribuídas em delineamento inteiramente casualizado em esquema fatorial (níveis de aflatoxina vs níveis de adsorvente) com 4 repetições, cada uma de 15 fêmeas e 2 machos. A partir da 65 a semana, as aves alimentadas com dietas contendo aflatoxina e adsorvente apresentaram menor taxa de postura em relação àquelas que receberam dietas comuns, sem esses aditivos. O peso corporal das matrizes, assim como o peso, o peso específico dos ovos, a eclodibilidade, e a qualidade dos pintos produzidos não são afetados pelos níveis de aflatoxinas e adsorvente presentes na dieta.Palavras-chave: glucomananos esterificados, micotoxinas, produção de ovos Productive performance of broiler breeders fed diets containing aflatoxins and esterified glucomannan as adsorbentsABSTRACT -The objective of this study was to evaluate the productive performance of broiler breeder hens fed diets containing aflatoxins and adsorbent on the basis of esterified glucomannan. It was used 300 Ross 308 females and 40 males broiler breeders, housed in 20 experimental pens in the 61-72 week of age phase. From the 61 st to the 68 th week, birds were fed diets containing three levels of aflatoxin (0; 0.500; 0.750 mg/kg) combined or not to adsorbent (0.10%) and on the last four weeks they received diets without aflatoxin and adsorbent. The birds were distributed in a complete randomized design in a factorial scheme (levels of aflotoxin vs levels of adsorbents) with 4 replicates, each one with 15 females and 2 males.From the 65 th week, birds fed diets with aflotoxin and adsorbent showed lower laying rate compared to those fed regular diets, without those additives. Body weight of the breeders as well as egg weight, specific egg weight, hatchability and quality of chicks produced are not affected by the levels of aflatoxins and adsorbent present in the diet.