ABSTRACT The objective of this study was to evaluate the effect of storage time on albumen quality, incubation yield, and hatch window in Pekin ducks (Anas boschas). A total of 1302 eggs were randomly distributed to seven treatments according to the storage time with durations ranging from 1 to 14 days. Each treatment consisted of 186 eggs with a two-day storage interval between treatments. The pH and Haugh unit (HU) of the albumen, egg weight loss during incubation (WL), hatchability (HTCH), incubation duration (ID), hatch window, asymmetry (ASS), percentile kurtosis (PK), and embryonic mortality were analyzed. A linear effect was observed forthe WL, ID, and PK and a quadratic effect forpH, HU, and HTCH over time. No significant effect of storage time was observed on ASS. Post-pipping embryonic mortality was linearly affected by storage time. Prolonging the storage period above 10 days reduces albumen quality and hatchability, delays the hatch of Pekins, and results in a higher percentage of post-pipping mortality.

ABSTRACT The aim of this study was to evaluate the possible effects of glutamine and broiler breeder age on the development of intestinal mucosa in broiler chicks during first week of age. For this purpose, 32 one-day-old broiler chicks were distributed according to a completely randomized experimental design in a 2 x 2 factorial arrangement. Treatments consisted of two broiler breeder ages (30 and 60 weeks) and two dietary glutamine supplementation levels (0% and 1%). The morphological development of intestinal mucosa, particularly villus height and crypt depth, was evaluated. The results showed that the supplementation with 1% of glutamine influenced the development of villus height in the duodenum (p=0.009), jejunum (p = 0.006), and ileum (p = 0.001), as well as crypt depth in the jejunum (p = 0.037) of 7-day-old broilers. These results suggest that the presence of glutamine influenced the development of intestinal mucosa during the first week of age, when these tissues are highly influenced by dietary components, especially by trophic agents. The results show that broiler breeder age (30 or 60 weeks) did not influence the evaluated parameters.

The present study evaluated the effect of feed particle size, thermal processing different levels of fat inclusion and of moisture addition on the amount of gelatinized starch in a corn-soybean broiler diet. The different processing factors were combined in a 2 x 4 x 4 x 2 factorial arrangement in a three randomized block design consisting of three production series: two particle sizes (coarse: 1041 microns and medium: 743 microns), four fat inclusion levels at the mixer (15, 25, 35, and 45 g/kg of feed), four moisture addition levels in the conditioner (0, 7, 14, and 21g/kg of feed), and two thermal processing treatments (conditioning-pelleting or conditioning-expanding-pelleting) which resulted in 64 different processed feeds. For the determination of the amount of gelatinized starch one feed sample was collected per treatment in each of three production series, totaling three replicates/treatment. Data were transformed using a variation of Box-Cox transformation in order to fit normal distribution (p>0.05). Adding moisture up to 21g/kg of feed in the conditioner linearly increased the amount of gelatinized starch (p<0.05). The conditioner-expander-pelleting treatment of the diets (at 110°C) increased (p<0.05) the degree of starch gelatinization from 32.0 to 35.3 % compared with the conditioner-pelleting treatment (at 80-82°C). The gelatinized starch content increased from 30.2 to 37.2% in the feed (p<0.05) as the particle size increased from medium to coarse. Fat inclusion had a quadratic effect (p<0.05) on starch gelatinization. The degree of starch gelatinization was significantly reduced with fat inclusion levels higher than 35 g/kg of diet. The factors evaluated in this study resulted in interactions and significant effects on degree of starch gelatinization.

Scientific information on the welfare of broilers reared in alternative systems is scarce. The objective of this study was to assess the welfare of free-range broilers using the Welfare Quality® protocol. Free-range broilers reared in ten farms were observed, and measures were made in broilers of five of these farms. The collected data were transformed into scores (0-100), with higher scores indicating better welfare, except for emotional states. Prevalence percentages were calculated for the remaining data. Median (min-max) scores were 81 (63-98) for lameness, 93 (83-99) for hock burn on the farm, 100 (95-100) for plumage cleanliness, 35 (8-70) for podermatitis on the farm, 56 (26-88) for density, 53 (20-53) for dust, 34 (14-67) for litter quality, 93 (41-100) for drinkers, and 100 (100-100) for birds panting or huddling on the farm. The following average (min-max) prevalence percentages were obtained: total mortality 2.0% (1.4-7.2%), culling 0.0% (0.0-2.2%), feed withdrawal time 875 min (715-945 min), water withdrawal time 220 min (170-275 min), dead on arrival at the processing plant 0.00% (0.00-0.01%), broken wings 0%, (0-0%), inefficient stunning 3.9% (1.3-6.7%), pre-stun shock 49.3% (26.7-56.8%), hepatitis 4.5% (1.8-11.0%), bruising 9.3% (6.7-16.7%), and ascites 0% (0-0%). The negative broiler welfare points detected were pododermatitis, litter quality, density, dust, culling, feed withdrawal time, inefficient stunning, pre-stun shock, and hepatitis. The positive points identified were the absence of birds panting or huddling on the farm; low prevalence of lameness, hock lesions, dead on arrival, broken wings, and ascites; good plumage cleanliness scores, and short water withdrawal time.

The study was designed to evaluate the productive consequences of fasting neonatal chicks obtained from strains genetically divergent for growing. Four hundred eight chicks from three strains, 160 from breeders selected for high growth rate and excellent feed conversion ratio (Cobb 500), 160 from breeders not selected for fast growth (JA57), and 160 from a white egg layer strain (Hy-Line W98) were allotted in a 3 (strain) x 2 (fasting period - 8 and 36h after hatching) factorial arrangement with 5 replicates of 16 chicks each. Immediately after hatching, all chicks had similar (P>0.05) relative yolk sac weights (14.13%, 14.50%, and 15.49% for Hy-Line, Cobb, and JA57, respectively). The yolk sac retractions were proportionally higher for Cobb and JA57 chicks up to 144 h (6 days) after placement, but were not influenced by 36h of feed fasting. At 7 and 14 days of age only Cobb chicks had their body weight and weight gain significantly (P<0.05) depressed by 36h feed fasting after hatching. Results indicate that broiler chicks with intense initial growth rates (Cobb 500) need an outstanding nutritional supply, either from exogenous (feed) or endogenous (residual yolk) sources, to achieve a final weight compatible with their genetic constitution. For slow-growing chicks (Hy-Line), nutritional supplementation via yolk sac seems to be more important than exogenous supply (feed) of nutrients during the neonatal period.

In order to evaluate the effects of broiler genotype and of heat exposure on performance, carcass characteristics, and protein and fat accretion, six hundred one-day-old male broilers were randomly assigned in a 2 x 3 factorial arrangement, according to the following factors: genetic group (selected and non-selected broilers) and pair-feeding scheme (Ad32 - reared under heat stress and fed ad libitum; Ad23 - reared at thermoneutrality and fed ad libitum; Pf23 - reared at thermoneutrality and pair fed with Ad32), with a total of six treatments with four replicates of 25 birds each. Independent of pair-feeding scheme, selected broilers showed better feed conversion, higher carcass yield, and lower abdominal fat deposition rate. However, as compared to non-selected broilers, they reduced more intensively feed intake when heat exposed, which promoted significant breast-yield decrease, and more pronounced changes on carcass chemical composition. These findings allows concluding that, in both genetic groups, both environmental temperature and feed-intake restriction influence abdominal fat deposition rate and other carcass characteristics; however, the impact of heat exposure on broiler performance is more noticeable on the selected line.

The objective of this experiment was to evaluate the effect of a probiotic (Bacillus subtilis, strain DSM 17299) in broiler diets on feed intake, weight gain, and feed conversion ratio. The experiment included 1,200 male Ross broilers from 1 to 42 days of age. Birds were randomly allocated to 4 treatments, with 10 replicates of 30 birds. The following treatments were applied: T1 - Negative Control (basal diet, with no added growth promoter; T2 - Negative Control + Bacillus subtilis (8 x 10(5) CFUs/g feed); T3 - Negative Control + Bacillus subtilis (3 x 10(5) CFUs/ g de feed) and T4 - Positive Control (avilamycin + anticoccidial from 1 to 35 days of age). At 21, 35, and 42 days of age, there was an increase of antibiotic-free diet intake as compared to the diets with growth promoters (p<0.05), but there was no difference, however, as compared to the diets with probiotic as a growth promoter (p>0.05). The use of growth promoter did not improve weight gain at the studied ages. There was a marked improvement in the feed conversion ratio of broilers fed the diet with antibiotics and of broilers fed the diet with added B. subtilis. It is concluded that the Bacillus subtilis probiotic can be used as a growth promoter in broiler diets.

In order to evaluate the effect of energy intake and broiler genotype on performance, carcass yield, and fat deposition, 600 one-day-old male chicks from two different genetic groups (AgRoss 308 - commercial line and PCLC - Embrapa non-improved line) were fed diets with different metabolizable energy level (2950, 3200 and 3450 kcal/kg). A completely randomized experimental design in a 2X3 factorial arrangement with four replications of 25 birds per treatment was applied. In order to ensure different energy intake among treatments within each strain, feed intake was daily adjusted by pair-feeding schemes. AgRoss 308 broilers had better performance and carcass yield, and presented lower abdominal fat deposition rate. In both genetic groups, the highest dietary energy level increased weight gain, heart relative weight, and fat deposition. However, it reduced the difference between AgRoss 308 and PCLC for feed conversion ratio and carcass protein deposition. These findings allow concluding that genetic improvement had a significant effect on broiler energy metabolism, and that the highest performance differences between genetic groups are found when low-energy intake is imposed.

The supplementation of vegetal diets with L-methionine (100% molar), methionine hydroxyl analogue (HMB) (88% molar) or DL-methionine (99% molar) was compared as to the performance of broilers allocated in cages and submitted to cyclic heat stress (CHS). The trial was carried out from 21 to 42 days of age. Two levels of synthetic methionine were supplemented for each methionine source (0.1 or 0.3 %), and the control treatment was not supplemented with synthetic methionine (negative control). Statistical analyses included the negative control treatment or were performed in a 3 x 2 factorial design (sources x levels). Addition of synthetic methionine to the basal level containing 0.63 % of total sulphur amino acids significantly improved feed conversion (FC) independent of the source. On the other hand, improvements in weight gain (WG) and body weight (BW) were more consistent comparing the negative control to HMB-supplemented treatments. Factorial analysis showed better FC for L-Met compared to DL-Met, whereas HMB showed intermediate results. The supplementation level of 0.3% methionine showed better FC than 0.1%. Methionine levels or sources had no effects on carcass, yields of cuts or feathering results. Therefore, results of DL-Met and HMB added to vegetal-based diets in comparable molar terms promoted similar performance in broilers under CHS conditions.

We studied the effects of two different systems of expressing amino acid requirements (total - TAA or digestible - DAA), two energy levels (2,900 or 3,200 kcal of ME/kg) and two physical forms (mash or pellet) on the performance of male broilers from 21 to 42 d of age. Diets formulated on DAA basis improved feed conversion (p<0.001) and the conversion of consumed ME into body weight gain (p<0.001). Birds fed 3,200 kcal ME/kg presented better feed conversion (p<0.001), higher abdominal fat deposition (p<0.001) and worse conversion of consumed ME into body weight gain (p<0.001) as compared to birds fed 2,900 kcal ME/kg. Birds fed pelleted feed had higher feed intake (p<0.001), higher weight gain (p<0.001), better feed conversion (p<0.001), better conversion of consumed ME into body weight gain (p<0.001) and higher abdominal fat deposition (p<0.001). The results obtained in the present study suggest that feed formulation based on DAA is required when diets contain protein sources which amino acid digestibility is unreliable. Besides, pelleted feed improves performance parameters of broilers.

This study was conducted to evaluate the performance and carcass and breast yields of broilers fed two different energy levels (3,200 or 2,900 kcal ME/kg) and two ways of expressing amino acid requirements (total - TAA or digestible - DAA) between 21 and 42 days of age. The results showed that broilers fed the diet containing 3,200 kcal ME/kg had higher weight gain (P=0.015), better feed conversion (P=0.001), and higher abdominal fat deposition (P=0.001) as compared to those fed the diet containing 2,900 kcal ME/kg. Diets formulated on DAA basis promoted higher weight gain (P=0.043), better feed conversion (P=0.010) and better conversion of ME intake into weight gain (P=0.007) as compared to those formulated on TAA basis. The results of this study suggest that formulation based on DAA is necessary if the diets contain protein sources that are not reliable in terms of amino acid digestibility. The response to formulation based on DAA was minimized when birds received the low energy level diet (2,900 kcal ME/kg).

The objective of this experiment was to investigate the effects of different particle sizes, expressed as Geometric Mean Diameter (GMD) of corn (0.336mm, 0.585mm, 0.856mm and 1.12mm) of mash and pelleted broiler chicken diets on the weight of the gizzard, duodenum and jejunum+ileum; on the pH of the gizzard and small intestine and on the characteristics of the duodenal mucous layer (number and height of villi and crypt depth) in 42-day-old broilers. The physical form and the particle size of the diet had no significant effect on gizzard and intestine pH (p > 0.05). A greater gizzard weight was seen in the birds receiving pelleted diet and particle size of 0.336mm (p < 0.008). However, for the particle sizes of 0.856 and 1.12 mm, a greater weight was found in birds that received mash diet (p < 0.039 and p < 0.006, respectively). Also, gizzard weight was greater with increasing corn GMD independent of the physical form of the diet. In the mash diet, the increase in particle size promoted a quadratic response in the weight of duodenum and jejunum + ileum. The pelleted diet promoted a greater number of villi per transverse duodenum cut (p < 0.007) and greater crypt depth (p < 0.05). As the particle size increased, there was a linear increase of villus height and crypt depth in the duodenum, irrespective of the physical form of the diet.

Este experimento foi realizado com o objetivo de investigar os efeitos de diferentes granulometrias, expressa em Diâmetro Geométrico Médio (DGM) do milho (0,336mm, 0,585mm, 0,856 mm e 1,12 mm) de dietas fornecidas na forma farelada (FAR) e peletizada (PEL), no desempenho e no rendimento de carcaça e de cortes de frangos de corte de 21 a 42 dias de idade. Dietas FAR, produzidas com DGM de 0,336 mm resultaram em um menor consumo (p<0,001), ganho de peso (p<0,001) e pior conversão alimentar (p<0,001) do que as PEL de mesmo DGM. Os demais DGM não mostraram diferenças entre ração FAR e PEL. Quando avaliada somente a granulometria, observou-se que o aumento no DGM melhorou o ganho de peso linearmente e de forma quadrática o consumo e a conversão alimentar. Não houve influência da forma física ou DGM em rendimento de carcaça e rendimento de perna+coxa. Porém foi verificada uma redução em rendimento de peito com DGM 0,336 mm (p<0,001), na forma FAR.

The experiment was conducted to evaluate the effect of different corn particle size, expressed as geometric mean diameter (GMD)(0.336 mm, 0.585mm, 0.856 mm and 1.12 mm) and two diet forms (mash-M and pellets-P) on performance and carcass yield of broilers from 21 to 42 days of age. M diets, produced with 0.336 mm of GMD resulted in lower feed intake (FI) (p<0.001), lower weight gain (WG) (p<0.001) and worse feed efficiency (FE) (p<0.001) than 0.336 mm P diets. M and P diets with other GMD did not show differences in performance. When particle size was evaluated itself, increments in GMD resulted a linear increase on WG and a quadratic increase on FI and FE. Neither form of diet nor particle size influenced carcass and leg+drumstick yields, although breast yield decreased with M diet,0.336 mm GMD (p<0.001).

Esse experimento foi realizado com o objetivo de avaliar a ação de produto de exclusão competitiva (EC) sobre os efeitos da ocratoxina A (OA). As aves alimentadas com 2 ppm de OA na dieta reduziram significativamente o consumo de ração e ganho de peso, além de apresentarem pior conversão alimentar quando comparadas às aves não expostas à OA na dieta. O emprego da EC no primeiro dia de vida não minimizou esses efeitos, bem como não afetou os parâmetros zootécnicos estudados. Aves alimentadas com OA apresentaram diminuição nos títulos vacinais contra o vírus da doença de Newcastle, evidenciando-se assim a interferência dessa micotoxina na resposta imune humoral de frangos de corte. De outra forma, a EC não interferiu na resposta imune humoral de frangos de corte vacinados contra a doença de Newcastle. Tanto a AO como a EC não alteraram os dados de altura de vilo, profundidade de cripta e relação vilo:cripta nas aves aos sete dias de idade quando comparados àqueles do grupo controle na mesma idade

This experiment aimed at evaluating the action of competitive exclusion (CE) on the effects of ochratoxin A (OA). Birds fed 2ppm OA in the diet had significant lower feed intake, weight gain, and feed conversion than birds not exposed to OA in the diet. The use of CE on the first day of age did not minimize these effects nor the performance parameters studied. Birds fed OA has lower vaccinal titers of Newcastle disease virus, showing the interference of this mycotoxin on the humoral immune response of broilers. CE did not interfere in the humoral immune response of broilers vaccinated for Newcastle disease. OA and CE did not influence villus height, crypt depth, nor villus:crypt ratio in seven-day-old birds as compared to control broilers of the same age.

Um experimento foi conduzido para estudar a adição do ovo em pó na dieta de frangos de corte no período de 1 a 28 dias, sendo dividido em duas fases (1 a 7 e 8 a 28 dias). No período de 1 a 7 dias, as aves receberam dietas contendo 0%, 5%, 10%, 15% e 20% de ovo em pó e de 8 a 28 dias de idade as aves foram distribuídas em um arranjo fatorial 2x5 (2 níveis de ovo em pó - 0% e 5% - e os 5 níveis da fase anterior). No período de 1 a 7 dias as aves do tratamento controle apresentaram melhor ganho de peso e as aves alimentadas com dietas contendo 20% de ovo em pó apresentaram menor ganho de peso e pior conversão alimentar. As aves deste mesmo tratamento apresentaram também menor peso e comprimento do intestino. Na segunda fase (8 a 28 dias) não houve interação entre os tratamentos estudados. O desempenho, peso e comprimento do intestino não foram afetados pelos tratamentos, ocorrendo apenas maior peso do coração em aves que receberam ovo em pó nesta fase. Os resultados obtidos demonstram ser economicamente inviável a utilização de ovo em pó na dietas de frangos de corte no período de 1 a 28 dias e pela falta de resposta que este ingrediente promove no desempenho da ave.

A experiment was conducted to study the addition of dried whole eggs (DWE) in broilers diets from 1 to 28 days of age in two phases (1to 7 and 8 to 28 days). From 1 to 7 days the birds received the diets with 0, 5, 10, 15 and 20% DWE and from 8 to 28 days of age the birds were assigned in a factorial arrangement 2x5 (2 levels of DWE - 0% and 5% - and the five previous levels). From 1 to 7 days of age birds fed control diet without DWE showed better weight gain and those fed the highest level of DWE showed the worst feed conversion. In the second phase (8 to 28 days) no interaction was found between treatments and also performance, gut weight and gut length were not affected by treatments. The results obtained suggest that the addition of DWE does not results in beneficial effects in broiler diets.