No abstract

Feed form is well recognized to improve broiler performance, specially by increasing feed intake (FI). However, when different diet energy levels are used, the results differ in the literature. Therefore, this experiment was conducted to evaluate the influence of feed form and dietary metabolizable energy (ME) levels on broiler performance, carcass yield and on the digestibility of DM, CP, starch and gross energy. In total, 1152 male Cobb 500 broilers were evaluated between 35 and 47 days. The birds were distributed according to a completely randomized design in a 2 × 4 factorial arrangement, consisting of two feed forms (mash or pellet) and four ME levels (12.73, 13.06, 13.40 or 13.73 MJ/kg), totaling eight treatments with eight replicates of 18 birds. Broilers fed the lowest ME level presented the lowest weight gain (WG) and worst feed per unit gain (P < 0.01). Metabolizable energy intake increased (P < 0.01) with progressive increments of ME, which, however, did not affect caloric conversion (CC, P > 0.05). Pelleted diets promoted higher FI, WG, ME intake (P < 0.01) and better feed per unit gain and CC (P < 0.05) compared with mash. In mash diets, increasing dietary ME levels promoted a linear increase in WG (P < 0.01) and reduced feed per unit gain (P ≤ 0.05), but did not affect FI (P > 0.05). In pelleted diets, on the other hand, increasing ME levels linearly reduced FI (P < 0.05) and feed per unit gain (P < 0.01). Broilers fed pelleted diets presented higher abdominal fat deposition than those fed mash (P < 0.05). Increasing ME levels reduced the coefficients of ileal apparent digestibility of DM (P < 0.01) and total starch (P < 0.05) but did not affect the digestibility of other evaluated nutrients. The digestibility of all nutrients was lower when pelleted diets were fed compared with mash. Increasing inert material inclusion in the diets at the expense of soybean oil to reduce dietary ME levels promoted higher pellet durability index values (P < 0.05) and the percentage of fines (P < 0.01). Overall, the results suggest that pelleted diets promote better broiler performance because they increase FI, since the digestibility of dietary fractions is reduced. Chickens consuming low-energy pelleted diets may increase FI to compensate for energy deficit. In contrast, broilers fed mash diets may have reached their maximum intake capacity and did not regulate FI by changing feed energy density. When feeding pelleted diets, dietary energy reduction should be considered to reduce feed costs and to improve the carcass quality of broilers.

Problems with indoor husbandry and immunological challenges are some of the stressors that broilers may face which can affect production. Infectious diseases can compound the effects of excessive concentrations of ammonia causing respiratory and ocular inflammation and increased lacrimal production in broiler chickens. The objectives of this investigation were to establish normal values of tear production in chicks and compare the practicality of the different methods. Palpebral fissure length (PFL) and tear production were evaluated in Cobb 500 chicks at 5 d old and then at 5 d of age by the following methods: modified Schirmer's test I (mSTT1), phenol red cotton thread tear test (PRCTTT), and standardized endodontic absorbent paper point test (EAPPTT). Ten chicks at the age of 5 and 42 d were evaluated for each method. In addition, at 42 d, when the palpebral fissure permitted, a regular-sized Schirmer tear test I (STT1) was performed in another group of 10 chickens. Overall, PFL and the secretion of the aqueous phase of the tear film increased with age. Mean mSTT1 results were 5.00 ± 1.83 mm and 10.45 ± 2.58 mm for 5- and 42-d-old chicks, respectively. Mean PRCTTT results were 12.37 ± 1.80 mm and 25.58 ± 4.8 mm for 5- and 42-d-old chicks, respectively. Mean EAPPTT results were 7.13 ± 0.72 mm and 12.03 ± 0.92 mm for 5- and 42-d-old chicks, respectively. Mean STT1 for 42-d-old chicks was 11.40 ± 2.60 mm. Results obtained with endodontic paper points showed the lowest coefficient of variation and investigators found the test easier to perform. These values reported for broilers at different ages may be applied in poultry ophthalmology to help the diagnosis of lacrimal production disorders and to detect early disease symptoms that could cause economic losses in poultry production.

No abstract

RESUMO:O objetivo foi avaliar a adição de simbiótico em rações para leitões na fase de creche com desafio nutricional. Foram utilizados 84 leitões, machos, castrados, em arranjo fatorial 2x2 (Dieta e Simbiótico), com 7 repetições e 3 animais por repetição. Tratamentos: DAD (dieta de alta digestibilidade), DBD (dieta de baixa digestibilidade), DAD+S (dieta de alta digestibilidade com simbiótico) e DBD+S (dieta de baixa digestibilidade com simbiótico). Variáveis estudas: ganho de peso diário (GPD), consumo médio de ração (CMR), conversão alimentar (CA) e frequência de fezes. Os parâmetros de desempenho foram comparados com o teste de Dunnett; considerando como controles a DAD e ausência de simbiótico. Para efeito da dieta, não foi observado diferença dos 21 aos 42 dias de idade, no entanto a DBD resultou em menor GPD (P<0,1) dos 42 aos 63 e menor CMR e GPD no período total (P<0,1). Por outro lado, a adição do simbiótico piorou (P<0,1) o CMR e o GPD dos 21 aos 42, o GPD e a CA dos 42 aos 63 e no período total (P<0,1). Na interação (dieta x simbiótico), dos 21 aos 42 dias de idade foi verificado melhor GPD e CMR no grupo com a DAD; enquanto, dos 42 aos 63, é observado piora (P<0,1) no GPD nos grupos com adição de simbiótico e piora na CA apenas no grupo DAD+S (P<0,1). No período total a DAD resultou em maior GPD (P<0,1). Quanto a frequência por tipo de fezes, o grupo com a DBD apresentou menor frequência do tipo normal e maior frequência do tipo aquosa (p<0,05). A utilização de dietas composta por ingredientes de alta digestibilidade é importante para o melhor GPD e CMR em fase de creche, enquanto que a adição do simbiótico estudado, em geral piorou o desempenho em ambos as dietas, podendo ainda aumentar a incidência de diarreia em leitões quando associado com DBD.Palavras-chave: desempenho; diarreia; dieta complexa; digestibilidade; suínos ABSTRACT: The aim was to evaluate the dietary inclusion of symbiotic in post weaning piglets with nutritional challenge. A total of 84 castrated male piglets were used in a 2x2 factorial arrangement (Diet and Symbiotic), with 7 replicates and 3 animals per replicate. Treatments: HDD (high digestibility diet), LDD (low digestibility diet), HDD+S (high digestibility diet with symbiotic) and LDD+S (low digestibility diet with symbiotic). Variables studied: average daily gain (ADG), feed intake (FI), feed conversion ratio (FCR) and fecal consistency. The performance parameters were compared with the Dunnett test; considering as controls the HDD and absence of symbiotic. In the diet factor, the DBD resulted in a lower ADG (P <0.1) from 42 to 63 and lower FI and ADG in the total period (P <0.1 ). On the other hand, the symbiotic inclusion worsened (P <0.1) FI and ADG from 21 to 42, ADG and FCR from 42 to 63 and in the total period (P <0.1). In the interaction (diet x symbiotic), from 21 to 42 days of age was verified better ADG and FI in the group with HDD; while, from 42 to

Many requirements are necessary to meet the European Union rules to export poultry, including the amount of physiological water and water-protein ratio ( WPR ) in carcasses. Therefore, the aim of this study was to identify if strain, nutrition, and age affect the amount of collagen and fat and the WPR in cuts and verify whether the latter meets the international export standards. A total of 3,240 male chicks were housed in a completely randomized design in a 3 × 3 × 5 factorial arrangement, which included 3 nutritional densities (regular, medium, and high), 3 strains (021 Embrapa and 2 commercial strains identified as A and B), and 5 ages. Twelve broilers from each treatment (totaling 540 birds) were slaughtered at 28, 35, 42, 49, and 56 D of age to determine collagen and fat levels and WPR (through the calculation of moisture and protein percentage) in broiler breasts and legs using the near-infrared spectroscopy method. The use of feeds with different nutritional densities presented in this study has no effect on the WPR in the breast and legs of broilers slaughtered between 28 and 56 D of age. However, nutritional density influences liveweight and percentage of fat in the breast and legs. Collagen percentage in the legs decreases with increasing nutritional density. The 021 Embrapa strain cuts present a lower WPR than those of other commercial strains. However, the values found for all strains studied are within the limits of the Europe Union and Brazilian legislations. The liveweight, breast weight, leg weight, and leg fat increases linearly with age. Quite the opposite, water protein ratio, breast fat level, and breast collagen level decrease linearly with age. Leg WPR and leg collagen level are not affected by age. Despite the differences found for strains, nutritional densities and age readers should be aware that these factors may interact with each other depending on the response variable studied.

This study evaluated the effect of birth weight and weight gain during the suckling phase on the piglet daily weight gain during the nursery phase (21-61 days of age). Piglets (n= 534) derived from 55 first-parity sows were weighed at birth, weaning, and end of the nursery phase. The data were analyzed according to a completely randomized experimental design, with three classes of birth weight (BW) and two classes of weight gain during the suckling phase (SDWG). High BW and low SDWG piglets were 0.2kg lighter at weaning than low BW and high SDWG animals (P< 0.05). However, at the end of the nursery phase, this situation was inverted, with high BW and low SDWG piglets 2.20kg heavier (P< 0.05). Low BW and high SDWG piglets were heavier at weaning and at the end of the nursery phase than low BW and low SDWG piglets (P< 0.05). At the same time, intermediate and high BW and low and high SDWG piglets presented body weight differences at weaning (P< 0.05), but not at the end of the nursery phase (P< 0.05). Piglets with 1.25 to 2.30kg BW and low weight gain during suckling presented a partial compensatory growth during the nursery phase.

No abstract