ABSTRACT Three experiments were carried out to evaluate the levels of digestible valine in diets with reduced crude protein on the performance, carcass yield and muscle fiber diameter of male broilers during the pre-starter (1 to 8 d of age), starter (9 to 21 d of age) and grower phases (21 to 42 d of age). A total of 1,080 chickens in the pre-starter phase, 900 in the starter phase and 864 in the grower phase were distributed in a completely randomized design with six treatments, consisting of a control positive diet (C+) and diets with 2 percentage points (p.p.) reduction of crude protein level and five graded levels of digestible valine (Val), with six replicates of 30, 25 and 24 birds per experimental unit, respectively. The recommended level of TID Val in the low-protein diets for broilers in the pre-starter, starter and grower stages were 1.028; 0.905 and 0.789%, respectively. The reduction of 2 percentage points of the crude protein level in diets based on corn and soybean meal impaired (p ≤0.05) the feed conversion ratio in the starter and grower stages. Likewise, the reduced-protein diets decreased (p ≤0.05) muscle fiber diameter, but did not affect (p> 0.05) carcass and parts yields, or abdominal fat percentage at 42 days.
The influence of age (85, 140, and 270 days) of European quails breeders on the egg quality and hatching, fertility and progeny performance was evaluated. The experimental design was completely randomized in a 3x3 factorial arrangement (females' age x males' age), with ten replicates and six birds per experimental unit (four females and two males). Egg production and quality were determined during 3 periods of 14 days and incubation parameters were evaluated in eggs obtained in five consecutive days. The live performance of the progenies was analyzed until 35 days. There was no effect of male age or any interaction between the age of males and females for the evaluated variable. The female's age influenced egg production, egg weight and chick weight, with better results obtained for 140-d-old breeders. The age of females reduced the hatchability, increased the late mortality in incubated eggs, and had no effect on fertility, total embryo mortality or eggshell structure, when analyzed by electron microscopy. The number of sperm trapped in the outer perivitelline layer (sptz/mm²) was determined in 10 fertile eggs per experimental unit. Young females fertilized by young males (80 days) had reduced sptz/mm². Progeny live performance was not affected by breeder's age. Breeders with 270 days retain fertility; however, their egg production, weight and hatchability of fertilized eggs is reduced. In conclusion, European quail breeders with 140 days of age have better egg quality, hatching and breeding results.
The aim of this study was to evaluate the supplementation of ethanolic extract of propolis (EEP) in broiler chickens diets on immune responses (humoral and cellular), weight of lymphoid organs and hematological profile. A total of 192 birds, raised in metabolism cages until the 21st day, were distributed in a completely randomised design with six treatments, eight replicates and four birds per experimental unit. The treatments consisted of diets containing 0; 1,000; 2,000; 3,000; 4,000 and 5,000 ppm of EEP. The inclusion of EEP gave a quadratic effect (P < 0.05) for relative weight of spleen and cloacal bursa, with the lowest weights found at the level of 2,946 ppm and 2,985 ppm of EEP, respectively. For the relative weight of thymus no change was observed (P > 0.05). There was no change (P > 0.05) in percentages of lymphocyte, heterophil, basophil, eosinophil and heterophil: lymphocyte ratio with the inclusion of EEP. However, there was a reduction (P < 0.05) in the percentage of monocyte to the inclusion level of 3,000 ppm of EEP when compared to control. The phagocytic activity of macrophages, the average number of phagocytised red cells and nitric oxide production were not affected (P > 0.05). The interdigital response to phytohaemagglutinin showed negative linear and quadratic behavior (P < 0.05) as a function of time and levels of inclusion, respectively, noting the smallest value of the reaction with 3,074 ppm of EEP. The birds showed a linear increase (P < 0.05) of serum antibodies against Newcastle disease, however, when each level of inclusion was compared to the control no difference was observed (P > 0.05). It is concluded that the addition of 1,000 to 5,000 ppm of EEP to the starter broiler diet did not have immunostimulant effect.
Este estudio evaluó la suplementación de extracto etanólico de propóleos (EEP) en dietas de pollos de engorde sobre la respuesta inmune (humoral y celular), peso de órganos linfoides y perfil hematológico. Se utilizaron 192 pollos de engorde, machos, criados en jaulas de metabolismo hasta los 21 días de edad. El diseño experimental fue completamente al azar con seis tratamientos, que consistieron en diferentes niveles de inclusión de EEP (0; 1.000; 2.000; 3.000; 4.000 y 5.000 ppm), con ocho repeticiones y cuatro aves por unidad experimental. La inclusión dietética de EEP provocó un efecto cuadrático (P < 0,05) en el peso relativo del bazo y bolsa de Fabricio, con menores pesos en pollos suplementados con 2.946 y 2.985 ppm de EEP, respectivamente. En el peso relativo del timo no se observó efecto (P > 0,05) de los tratamientos. La inclusión de EEP no alteró (P > 0,05) el porcentaje de linfocitos, heterófilos, basófilos, eosinófilos y la relación heterófilo:linfocito. Hubo reducción (P < 0,05) en el porcentaje de monocitos con la inclusión de 3.000 ppm de EEP en comparación al control. La actividad fagocítica de los macrófagos, número promedio de eritrocitos fagocitados y producción de óxido nítrico no fueron alterados (P > 0,05). La reacción interdigital a la fitohemaglutinina presentó efecto lineal negativo y cuadrático (P < 0,05) en función del tiempo y de los niveles de inclusión, respectivamente, resultando en menor reacción con el nivel de 3.074 ppm de EEP. Hubo aumento lineal (P<0,05) de los niveles de anticuerpos séricos contra la enfermedad de Newcastle al incrementar el nivel de EEP en la dieta; sin embargo, al comparar cada nivel de inclusión del extracto con el control no hubo diferencias (P < 0,05). Se concluye que la inclusión de 1.000 a 5.000 ppm de EEP en la dieta inicial de pollos de engorde no demostró efecto inmunoestimulante.
This study evaluated the performance and the quality and fatty acid profile of eggs from laying hens fed diets containing mixed crude glycerin (MCG; 80% vegetable fat + 20% animal fat). A total of 240 39-week-old Hy-Line W36 laying hens were distributed according to a completely randomized experimental design into six treatments consisting of graded MCG dietary inclusion levels (0, 1.5, 3.0, 4.5, 6.0, and 7.5%), with five replicates of eight birds each. Feed intake linearly decreased (p<0.05) with increasing MCG inclusion levels. The percentages of myristic, palmitic, and α-linolenic acids in the eggs linearly decreased as MCG dietary levels increased (p<0.05), while α-linoleic acid, polyunsaturated fatty acids (PUFA) and ω-6/ω-3 ratio linearly increased. Excreta moisture linearly increased with increasing levels of MCG inclusion (p<0.05). MCG may be included in up to 7.5% in layer feeds without impairing performance or egg quality, but levels up to 5.54% reduce SFA egg content. However, the inclusion of MCG in layer diets increases ω-6/ω-3 ratio in the eggs.
The aim of this experiment was to evaluate the effect of sources of trophic action (glutamine alone, glutamine associated with glutamic acid and yeast) associated with vaccination against coccidiosis on the performance and morphometry of the small intestine of broilers. In the trial, 1,200 broiler chicks were distributed according to a completely randomized design with a 3 x 2 + 2 (trophic action x vaccination or not + control - free trophic factor) factorial arrangement, with five replicates of 30 birds each. Vaccination negatively affected performance parameters and the morphometry of the intestinal mucosa, but at the end of the experimental period, among the broilers vaccinated against coccidiosis, the group fed glutamine presented better recovery from epithelial losses of the intestinal mucosa compared with the control groups. Therefore, the dietary supplementation with the evaluated sources of trophic action could be a strategy to enhance the development of broilers submitted to vaccine stress, also considering the economic viability of the productive segment.
The influence of supplementing the diet of broiler breeder hens with arginine (Arg) on their offspring's humoral and cell-mediated immune response was evaluated in two experiments. In experiments I and II, breeder hens were fed diets containing graded levels of Arg (0.943, 1.093, 1.243, 1.393 and 1.543% digestible Arg). In experiment I, the offspring was randomly grouped according to the treatment received by the breeder hens, with five levels of Arg in the maternal diet and six replicates, giving a total 30 experimental units. In experiment II, the offspring were grouped in accordance with the treatment received by the breeder hens; however, Arg was added to the starter diet (1.300, 1.450, 1.600, 1.750 and 1.900% digestible Arg) and also the growing diet (1.150, 1.300, 1.450, 1.600 and 1.750% digestible Arg). Supplementation of the broiler breeder hen diet did not influence (p > 0.05) the development of the lymphoid organs (cloacal bursa, thymus and spleen) of the offspring, whether their diet were supplemented or not. Nevertheless, greater weight and dimensions cloacal bursa were found in the supplemented offspring in comparison with the nonsupplemented offspring. Macrophage phagocytic activity was found to be unaffected (p > 0.05), independently of the Arg supplementation. The offspring fed with supplemented diets showed a linear reduction in the antibody titer against Newcastle Disease (p < 0.05) at seven days of age, and a quadratic response (p < 0.05) at 28 days of age. The antibody titer in the non-supplemented offspring was not influenced (p > 0.05) by the breeder hen diet. This study concluded that supplementing the breeder hen diet with arginine is insufficient to improve the humoral and cellular immune response, requiring supplementation of the offspring diet.
This study evaluated the effects of different sources of vitamin D and calcium levels on performance, egg quality and bone strength of hens in the second production cycle. A total of 384 Hy-Line W36 birds with 80 weeks of age were used, alloted into 3 x 4 factorial design (sources of vitamin D: cholecalciferol; 25(OH)D3 and 1.25(OH)2D3 x calcium levels: 2.85, 3.65; 4.45 and 5.25%) with four replicates and eight birds each. The performance was evaluated for three cycles of 28 days each, egg quality was evaluated in the last four days of each cycle and bone strength on the last day of the experimental period. There was no interaction (p > 0.05) between the different sources of vitamin D and calcium levels in all parameters evaluated. There was a quadratic effect (p < 0.05) of calcium levels in egg production and feed conversion (kg/kg and kg/dz), with better results at levels of 4.12%, 4.09% and 4.14%, respectively. Calcium levels had no effect (p > 0.05) in the egg weight and Haugh unit, but there was a linear increase (p < 0.05) in the percentage and eggshell thickness, in specific gravity and bone strength. The different sources of vitamin D influenced (p < 0.05) the egg production rate, feed conversion, egg weight and Haugh unit. Thus, the results of this study suggest that the recommended calcium level for laying on second cycle is between 4.09% and 4.14% and that the metabolites cholecalciferol and 25(OH)D3 improved the performance and egg quality. Regarding bone strength was improved as the calcium levels were increased in diets.
Vitamin K is involved in blood clotting process and plays an important role in bone formation. Thus, this study aimed to evaluate the supplementation of different levels of vitamin K3 on growth performance and bone parameters of broiler chickens. For this purpose, 1,500 broiler chickens were distributed in a completely randomized experimental design. The treatments consisted of a control diet containing 1.6 mg of vitamin K3/kg of diet and 5 levels of vitamin K3 (11.6 mg/kg; 21.6 mg/kg; 41.6 mg/kg, 61.6 mg/kg and 81.6 mg/kg), with 5 replicates and 50 chickens per experimental unit. At 7, 21, and 40 days of age, growth performance (body weight, body weight gain, feed intake and feed:gain ratio) and bone parameters (bone length and diameter, Seedor index and bone strength) were evaluated. The increase in vitamin K3 levels improved the feed intake, body weight and body weight gain in the pre-initial phase. At 40 days old, all performance parameters were similar among the different levels of vitamin K3. At 21 and 40 days of age, bone parameters were impaired as dietary levels of vitamin K3 increased. The results suggest that the recommended level of vitamin K3 in broiler chicken diets is 1.6 mg/kg of diet.
La vitamina K participa en los procesos de coagulación sanguínea y también tiene un importante papel en la formación de los huesos. Así, el objetivo de este estudio fue evaluar la suplementación de diferentes niveles de vitamina K3 sobre el comportamiento productivo y indicadores óseos de pollos de engorde. Se utilizaron 1.500 pollos de engorde, distribuidos en un diseño experimental completamente al azar. Los tratamientos consistieron en una dieta control conteniendo 1,6 mg de vitamina K3/kg de dieta y de 5 niveles de vitamina K3 (11,6 mg/kg; 21,6 mg/kg; 41,6 mg/kg, 61,6 mg/kg y 81,6 mg/kg), con 5 repeticiones de 50 aves/unidad experimental. A los 7, 21 y 40 días de edad, los indicadores de comportamiento productivo (peso promedio, ganancia de peso, consumo de dieta y conversión alimentaria) y los indicadores óseos (longitud y diámetro de los huesos, índice de Seedor y resistencia ósea) fueron evaluados. El aumento en los niveles de vitamina K3 mejoró el consumo de dieta, peso promedio y la ganancia de peso en la fase pre-inicial. A los 40 días de edad, todos los indicadores de comportamiento productivo fueron similares entre los diferentes niveles de vitamina K3. Los indicadores óseos empeoraron a los 21 y 40 días de edad con el aumento en los niveles de vitamina K3. Estos resultados sugieren que el nivel indicado de vitamina K3 en las dietas de pollos de engorde es de 1,6 mg/kg de dieta.
This study investigated the effects of arginine (Arg) supplementation on broiler breeder egg production and egg quality. Male (30) and female (360) Ross® breeders, totaling 390 birds, were studied. A completely randomized design with five Arg levels (0.943%, 1.093%, 1.243%, 1.393%, 1.543% digestible Arg) and six replicates of 12 females and one male per experimental unit was applied. The following performance and egg quality were evaluated: lay percentage, albumen and yolk contents, average egg weight, egg specific gravity, and eggshell percentage and thickness. Hatchability and and embryo mortality were also determined. The applied dietary digestible Arg levels quadratically influenced egg production (p<0.05), with the highest production obtained when 1.262% digestible Arg was supplemented. Egg weight linearly increased (p<0.05) with digestible Arg dietary level; however, egg specific gravity linearly decreased (p<0.05). Hatchability was not affected (p<0.05) by digestible Arg level. The supplementation of broiler breeder diets with Arg improved egg production and egg weight without any effect on hatchability. Further research is needed to determine the effect of dietary Arg supplementation on the performance of the progeny.
Egg- and meat-type quails were reared in groups of different sizes with a fixed female-to-male ratio of 2 to 1 and an area of 158 cm² per bird. The aim was to investigate the influence of group size on quail production and reproductive variables. To this end, 360 quails (180 meat and 180 egg-type quails) were assigned in a completely randomized experimental design to one of three treatments with ten replicates each. The treatments consisted of groups with nine, six, or three quails per cage. Birds were observed for three cycles of 14 days. Daily feed intake and feed conversion ratio were influenced (p < 0.05) by group size in both types of quails. Quail type influenced (p < 0.05) daily feed intake, feed conversion, and egg weight due to the typical differences between meat and egg-type birds. Despite the observed differences in production parameters, the mean values observed were typical of meat- and egg-type quails. The number of hydrolysis points (holes) per mm² on the vitelline membrane on the germinal disc area was higher in meat quails (2.89 ± 0.21) than in egg quails (2.15 ± 0.13). This parameter was not influenced by the number of birds per cage, which suggests that the number of males inside the cage did not modify the spermatozoa pool inside the female oviduct. We concluded that a ratio of two females per male in cages with three, six, and nine birds/cage is recommended, as no deleterious effect on quail reproduction was observed.
The aim of this experiment was to determine the productive performance and egg quality of Japanese quails fed different types of processed rations (mash, extruded, or pelleted). One hundred and forty-four 18-w-old quails (Coturnix coturnix japonica) were housed in galvanized wire cages and fed a 21.50% CP and 2850 kcal ME/kg basal feed supplied in mash, extruded, or pelleted form. Experimental data were analyzed by ANOVA as a complete randomized design, with three treatments (ration forms) and six replicates of eight quails each. When necessary, means were compared by Tukey's test at 5% significance. Quails fed pelleted feed presented higher egg production, feed intake, and egg mass weight as compared to mash- and extruded-diet-fed birds. Under the conditions of the present experiment, it was possible to conclude that the feed physical form did not affect egg quality, except for pelleted diets, which promoted good production performance and high egg mass. However, the use of feed pelleting should be economically analyzed considering the final cost of egg production.
Two experiments were carried out to evaluate the performance, abdominal fat yield, and bone parameters of broiler chickens fed diets containing different lipid feedstuffs as energy source. During the starter phase (1 to 21 days) of Experiment 1, a completely randomized design with four treatments with eight replicates of 49 birds each one was applied. Broilers were fed starter diets formulated with different lipid sources: soybean oil (SO), cottonseed oil (CO), poultry offal oil (PO), and beef tallow (BT). During the finisher phase (21 to 42 days) of Experiment 1, each initial treatment was divided in two experimental groups: one fed the same fat ingredient as the previous period, and the other fed SO as energy source. Thus, during this period, a completely randomized design with seven treatments, four replicates, and 43 broilers per experimental unit was tested. During the starter phase (1 to 21 days) of Experiment 2, all broilers were fed with the same soybean oil-supplemented diet. The experimental groups were divided during the finisher phase (21 to 42 d) in a completely randomized design with five treatments groups with six replicates of 30 birds each. During this period, treatments consisted of diets formulated with SO, rapeseed oil (RO), sunflower oils (SFO), PO, or BT as lipid sources. No effects (P>0.05) of the treatments on any of the studied parameters were observed in either experiment. Results suggest that there is no influence of animal or vegetable dietary lipid sources on performance, abdominal fat deposition, or tibia density and strength in broilers.
This trial aimed at evaluating the effect of organic trace mineral supplementation of commercial layer diets on productive performance and egg quality. One-hundred-ninety-two Hy Line W36 white 69-w-old layers were distributed into a completely randomized design with three treatments, and eight replicates, with eight birds each. Treatments consisted of a basal diet supplemented with inorganic trace minerals (R1), and two others experimental diets containing 0.250 ppm (R2) and 0.500 ppm (R3) of an organic source of zinc, manganese, and selenium. Feed intake (g/bird/day), feed conversion ratio (kg/dozen egg and kg/kg egg), egg weight (g), egg production (%), thin and cracked eggshells (%), specific gravity (g/mL), Haugh Units, total egg solids (%), yolk yield, white and shell yields (%), eggshell thickness, and egg Se content were evaluated Tukey's test analyzed differences among means at 5% of probability using PROC GLM in SAS (2000). Although not significant as compared to the non-supplemented diet, improvements on relative cracked-plus-thin shells were observed with the use of organic mineral blend. The addition of the organic blend to the diet at 0.250 kg/ton resulted in (p<0.05) higher total egg solids. Also, as compared to eggs from control group, fresh and dried yolk yields were higher with the dietary inclusion of the organic mineral blend at 0.250 and 0.500 kg/ton.
This experiment studied the influence of delayed placement (HI) and digestible lysine level (DL) on the morphometrics of the intestinal mucosa and on the performance of broilers. A total number of 1,705 Cobb 500 male chicks were used in a completely randomized experimental design in a factorial arrangement with four HI (12, 24, 36 and 48h), and two DL level in the starter diet (1.143 and 1.267%), with four replicates and 55 birds per experimental unit. The amino acids methionine-cystine, threonine, and tryptophan were balanced according to the ideal protein (IP) concept. Small intestine morphometrics was evaluated using histology slides of the duodenum and jejunum. There was no interaction between HI and DL levels for any of the studied parameters. The 1.143% level of DL promoted better performance results at 21 and 42 days of age, as well as higher duodenum and jejunum crypt depth, and duodenum villi height at 21 days of age. HI negatively influenced the morphometrics of the small intestine during the starter phase, and the performance of broilers up to 42 days of age. There was no effect of the treatments on yolk sac utilization or abdominal fat percentage. It was concluded that the use of 1.143% DL and HI of 12 hours promoted better development of the small intestine mucosa up to 21 days of age, and broiler performance at market age.
This study aimed at evaluating the influence of Glutamine (Gln) and Vitamin E (VE) supplementation on the performance and immune response of broilers. A completely randomizes experimental design with a 2 x 3 (VE x Gln) factorial arrangement was used. VE was supplemented at 10 and 500 mg/kg feed, with or without Gln (1%) addition, and two periods of supplementation in the starter diets (1-7 and 1-14 days of age), with five replicates of 50 birds each. The analyzed parameters were: live performance (weight gain, feed intake, and feed conversion ratio); relative weights of the spleen, bursa, and thymus; antibody titers (with sheep red blood cells suspension - SRBC) and cutaneous basophilic hypersensivity (CBH). Data were submitted to the analysis of variance, and means were compared using the test of Tukey. Treatments did not influence (P>0.05) live performance parameters or antibody titers. VE reduced (P=0.01) CBH, with the level of 10 mg VE/kg allowing higher cell proliferation as compared to 500 mg VE/kg. As to lymphoid organs, only the spleen was affected (P=0.035) by Gln, which resulted in higher spleen relative weight when fed during the first week of age. Results showed that 10 mg VE/kg with Gln (1-7 days) promoted better immune responses.