ABSTRACT The objective of this study was to assess the effects of high-concentrate diets with and without the inclusion of soybean hull (SH; 0 or 500.8 g/kg) plus corn (whole or ground) on the performance, morphometric traits, and nutritional and metabolic parameters of crossbred dairy calves. We also aimed to assess the costs associated with the experimental diets employed. Thirty-six male calves with an average weight of 89±18.6 kg and age of 3.5 months were allocated to four treatments, with nine replicates of one calf/pen, in a completely randomized experimental design for 198 days. The inclusion of the SH and the physical form of corn did not influence animal performance or morphometric measurements; however, SH inclusion increased the digestibility of neutral detergent fiber and the intakes of dry matter and neutral detergent fiber, but did not affect total digestible nutrient intake. The physical form of corn did not influence nutrient intake or digestibility, which resulted in similar performance across the animals. Blood glucose levels as well as alkaline phosphatase and creatinine remained elevated regardless of the diet. The use of SH reduced the total plasma cholesterol content, and there was an interaction between the physical form of corn and SH inclusion in relation to creatinine levels, which were higher when using diets with whole corn and SH. Although the inclusion of up to 500.8 g/kg of SH in the diet reduces feed efficiency, its use decreases the cost per kilogram of weight gain. Dairy calves can exhibit satisfactory production performance when fed alternative ingredients such as whole corn or SH, which have a lower cost than ground corn, traditionally used in diet formulations. highconcentrate high concentrate (SH 5008 500 8 500. gkg g traits employed Thirtysix Thirty six 89186 89 18 6 89±18. 35 3 5 3. treatments calfpen calf pen calf/pen 19 days measurements however animals content efficiency gain formulations 50 8918 1 89±18 891 89±1 89±

ABSTRACT. To gain insights into the forage morphological and anatomical characteristics in a silvopastoral system (SPS) with Bolsa de Pastor (Zeyheria tuberculosa) and palisadegrass ‘Marandu’ (Urochloa brizantha) monoculture (MONO). The SPS was established through natural regeneration of the tree species. Treatments were a SPS and MONO distributed in a completely randomized design with six replicates and repeated measures were the harvest periods. Response variables were morpho-physiological and anatomical characteristicss: green: dead material ratio, leaf blade: stem+sheath ratio, leaf area index, chlorophyll and carotenoid concentrations, proportions of non-lignified and achlorophyllous areas, lignified areas in stems, proportions of non-lignified and achlorophyllous areas, lignified and chlorophyllous areas in leaves, as well as cell length in longitudinal section of stem. Morpho-physiological patterns were altered (p < 0.05) under natural shading conditions due to higher photosynthetic efficiency in the SPS. There was no effect (p > 0.05) of the systems on anatomical patterns, proportions of non-lignified and achlorophyllous, lignified and chlorophyllous tissues, these proportions were influenced only by the periods of the year, both for stems and leaves. Cells of the internodes of the grasses of the studied systems had the same length. The SPS alters morpho-physiological characteristics of palisadegrass and increases the concentration of chlorophyll a and b. ABSTRACT (SPS Zeyheria tuberculosa ‘Marandu Marandu Urochloa brizantha MONO. . (MONO) species morphophysiological morpho physiological characteristicss green ratio blade stemsheath stem sheath index concentrations nonlignified non leaves Morphophysiological Morpho p 0.05 005 0 05 tissues year b (MONO 0.0 00 0.

ABSTRACT This study mapped cattle carcass lesions and associated the isoline maps with the occurrence factors of these lesions. Isoline maps were drawn by common kriging. The associated occurrence factors were the layout of the boards in the crowding tub (CT), characteristics of the hauling truck (general state and the presence of loose and/or sharp boards), broken boards in the corral (BBC), type of road covered (TRC), and animal falls upon unloading at the slaughterhouse (FAUS). The BBC showed a higher number of carcass lesions in the rib region. The data on FAUS and deterioration of hauling trucks fit an exponential model, with more carcass lesions in the rib and hindquarters, and plate regions, respectively. The data on spaced boards in the CT and TRC (mixed) showed greater carcass lesions in the rib region. Therefore, this method provides important information about the spatial distribution of lesions in bovine carcasses, and the drawing sheet used is adequate to represent such lesions. kriging CT, , (CT) general andor or boards, boards) BBC, (BBC) TRC, (TRC) FAUS. . (FAUS) region model hindquarters regions respectively mixed (mixed Therefore carcasses (CT (BBC (TRC (FAUS

ABSTRACT. The objective was to evaluate the performance and ingestive behavior of grazing sheep in the finishing stage, with supplementation in the period of water restriction. Fifteen male crossbred sheep were used in continuous pasture in Massai grass and supplied supplement formulated with 18% of crude protein in three levels (0.0; 0.3 and 0.6% of body weight), individually. Bromatological and fodder production analyses were performed, as well as foliar mass production, stem mass and senescent material mass. The performance and ingestive behavior of the animals were evaluated. The design was in four randomized blocks for the variables measured in the fodder. For the biometry, weight gain and behavior variables measured in the animals, the design was entirely randomized with five repetitions. The total forage mass production was 5512.41 kg ha-1, with 6.58% of crude protein, 79 38% of neutral detergent fiber and with 65% of foliar mass. The total weight gain and daily weight gain were higher in animals that received a supplement of 0.6% of body weight. In general, the animals grazed more in the morning period and the supplemented ones destined more time for rumination and leisure than the ones not supplemented.

The purpose was to evaluate the effect of extruded roughage Foragge® with different additives on intake, digestibility nutrients and nitrogen balance of sheep. Twenty adults, non-pregnant ewes with average weight 68 kg were used. The treatments were extruded roughage with additives (essential oil, virginiamycin, unpurified inactive yeast, tannin and purified inactive yeast). The design was in randomized blocks. The means were contrasted by SNK test, and the fecal score was tested by the Kruskal Wallis test (1952), at 5% significance. There was no difference in the intake of dry matter, crude protein, nitrogen, water, water in relation to dry matter, neutral detergent fiber (NDF), and acid detergent fiber (p > 0.05). As well as the digestibility of dry matter, crude protein and neutral detergent fiber, the fecal weight, fecal nitrogen, retained nitrogen and nitrogen retained in relation to nitrogen ingested (p > 0.05). However, dry matter intake as a function of body weight and metabolic weight, urinary nitrogen, hemicellulose intake, and hemicellulose as a function of NDF, were higher in the Foragge Factor® treatment (p < 0.05). The inclusion of different additives in the extruded roughage improved nutritional parameters, without causing disturbances.

ABSTRACT. The objective of this study was to evaluate the effect of adding exogenous enzymes to the diet on nutrient intake and digestibility, nitrogen balance, ingestive behavior and rumen movement of ewe lambs. Five ewe lambs, Dorper x Santa Inês crossbred, with an average age of 7 ± 1 months, average weight of 36.40 ± 2.36 kg were assigned in a 5x5 Latin square design. The treatments consisted of adding exogenous enzymes to the concentrate: Allzyme, Fibrozyme®, Amaize®, Mix and Control. Analyses of variance were applied and means were compared by the SNK test, and non-parametric Kruskal Wallis test at 5% significance. The dry matter intake in relation to body weight, crude protein intake and nitrogen intake were higher with the use of amylolytic enzyme compared to the other treatments (p <0.05). Nitrogen balance was higher with the use of amylolytic enzymes and the Allzyme® enzyme complex (p <0.05). A longer time spent in total chewing was observed with the inclusion of fibrolytic and amylolytic enzymes without changes in rumen movement. The use of exogenous enzymes promotes better use of nutrients, with high digestibility of dry matter, neutral detergent fiber and crude protein.

RESUMO Objetivou-se avaliar o efeito da adubação fosfatada nas características morfogênicas e estruturais do capim Mombaça sob condições de implantação de sistema silvipastoril com eucaliptos e monocultivo no ecótono Amazônia/Cerrado. O experimento foi conduzido na UFT-EMVZ, nas estações chuvosas dos anos agrícolas de 2016/2017 e 2017/2018. Área experimental foi subdividida em dois sistemas de cultivo, Monocultivo de capim Mombaça, com 0,25 hectare e Silvipastoril com consórcio de eucalipto e capim Mombaça com área de 0,75 hectare. O delineamento utilizado foi um Delineamento inteiramente casualizado em esquema fatorial 4 a 2 sendo quatro doses de fósforo (0; 50; 100; 200 kg. ha-1 de P2O5. ano-1) e dois sistemas de cultivo (monocultivo e silvipastoril), com três repetições. Foram avaliados três ciclos por período de descanso médio de 21 dias. Semanalmente foram realizadas as medições para avaliação das características estruturais e morfogênicas das plantas. De forma geral, fatores testados como adubação fosfatada, sistema de cultivo e ano de condução (implantação e ano seguinte) apresentaram influência, alterando o desenvolvimento do capim Mombaça, refletindo nas características morfogênicas e estruturais. As variáveis: densidade populacional de perfilhos, taxa de crescimento cultural, índice de área foliar, obtiveram interações entre a adubação fosfatada e os sistemas de cultivos analisados (P<0,05). A adubação fosfatada utilizada na implantação momento este de a de maior requerimento da planta, refletiu no desenvolvimento da forrageira aumentando a taxa de crescimento cultural, aparecimento foliar, bem como alongamento de folhas e colmo nos dois sistemas avaliados.

ABSTRACT The objective of this study was to evaluate the effect of phosphate fertilization on morphogenic and structural characteristics of Mombasa grass under conditions of implantation of silvopastoral system with eucalyptus and monoculture in the Amazon/Cerrado ecotone. The experiment was conducted at UFT-EMVZ during the rainy seasons of the 2016/2017 and 2017/2018 agricultural years. The experimental area was subdivided into two cultivation systems, Mombaça grass monoculture, with 0.25 hectare and silvopastoral system, intercropping eucalyptus with Mombaça grass, with 0.75 hectare area. The design used was a 4 x 2 factorial IHD with four doses of phosphorus (0; 50; 100; 200 kg.ha -1 P2O5 year-1) and two cultivation systems (monoculture and silvopastoral) with three repetitions. Three cycles were evaluated for an average rest period of 21 days. Weekly measurements were taken to evaluate structural and morphogenic characteristics of plants. In general, factors tested such as phosphorus fertilization, cultivation system and year (implantation and following year) showed influence, altering the development of Mombaça grass, reflecting on the morphogenic and structural characteristics. Tiller population density, crop growth rate, leaf area index showed interactions between phosphorus fertilization and the cultivation systems analyzed (P <0.05). Phosphorus fertilization used in the implantation, moment of greatest requirement of the plant, influenced forage development by increasing the crop growth rate, leaf appearance, as well as leaf and stem elongation in the two evaluated systems.

ABSTRACT. The purpose of the current study was to evaluate the in vitro fermentation (IVRF) and apparent in vivo digestibility (AIVD) of diets formulated with four inclusion levels of babassu mesocarp meal (BMM) (0.0; 7.5; 15.0 and 22.5%) in ewe lambs. The IVRF test was performed through the "Hohenheim Gas Test" technique, following a randomized complete block design, with four blocks (rumen fluids from four different bovines). Gas production was measured at 3, 6, 9, 12, 24, 48, 72, and 96 hours after incubation. For the AIVD trial, 20 ewe lambs were used in a completely randomized design with five replicates. The animals were housed in metabolic cages during the digestibility test. Diets with BMM showed lower fermentation levels than those without BMM. The BMM reduced the gas production per incubation time and dry matter effective degradability (DMED), possibly due to its chemical characteristics, or even to the influence of other factors, such as physical properties. The BMM negatively influenced the AIVD of DM. Thus, it can be stated that, despite being a starch source, BMM reduces ruminal fermentation parameters when included in ruminant diets, negatively interfering with diet digestibility. Therefore, its use should be cautious.

ABSTRACT The objective of this study was to evaluate performance, apparent digestibility, blood parameters, and quantitative characteristics of carcass and internal organs of crossbred dairy calves fed different levels of crude glycerin in corn grain-based diets. Twenty-four calves of three months of age and average initial weight of 95.5±11.8 kg were used. The experimental design was completely randomized with four treatments (0, 80, 160, and 240 g kg−1 of crude glycerin of DM of diets). The calves were fed in feedlot until six months of age (195.68±2.38 kg of BW). Dry matter (4.14, 4.11, 3.80, and 3.49 kg day−1) and apparent digestible energy intake (0.43, 0.41, 0.37, and 0.35 MJ kg−1 BW) decreased with increasing levels of glycerin in the diets. There was no effect on the apparent digestibility of nutrients, average daily gain, feed efficiency, carcass characteristics, and blood parameters. The diets did not influence the weights [g kg−1 of empty body weight (EBW)] of lungs, heart, kidneys, liver, omasum, abomasum, and large intestine. The reticulorumen weight (g kg−1 EBW) increased, whereas the small intestine weight decreased with increased levels of glycerin in the diets. The area, height, and width of the rumen papillae were not changed with increasing levels of glycerin. The rumen wall thickness increased with increasing levels of glycerin in the diets. The inclusion up to 240 g kg−1 DM of crude glycerin of in corn grain-based diets for the production of dairy calves does not alter animal performance, carcass characteristics, and weights of internal organs.

RESUMO O objetivo foi avaliar a influência de três alturas pré-pastejo do capim Massai sobre o comportamento ingestivo de ovinos sob lotação rotativa. Foram utilizados 18 ovinos mestiços Dorper x sem padrão racial definido (SPRD) sob lotação rotativa em capim Massai nas alturas pré-pastejo de 45, 35 e 25 cm. A lotação animal foi estimada para garantir a redução de aproximadamente 50% da altura inicial. As avaliações de comportamento foram feitas das 6 às 18 h na entrada e na saída dos animais dos piquetes. A maior atividade de forma geral realizada foi a de pastejo, seguida de ruminação e outras atividades, sendo o período de 6 às 10 h o que apresentou maior atividade de pastejo. Nos demais períodos, os animais no tratamento com 35 cm pastejaram menos que os animais dos outros tratamentos. A ruminação, em todos os tratamentos, foi mais significativa no período das 14 às 18 h, mas os animais no tratamento com 45 cm foram os que passaram maior tempo realizando esta atividade. Os animais no tratamento com 45 cm apresentaram maior tempo de ruminação do bolo alimentar e maior número de mastigações merícicas. A taxa de bocados foi superior para o tratamento com 25 cm, seguido do com 45 e 35 cm respectivamente.

SUMMARY This studyaimed to assess the influence of three pre-grazing heights of Massai grass on the ingestive behavior of sheep under rotational stocking. Eighteen Dorper x nondescript crossbred sheep were used under rotational stocking on Massai grass at pre-grazing heights. The animal stocking was estimated to ensure a reduction of approximately 50% of the initial height. Behavior assessments were performed from 6 to 18 h at the entrance and exit of animals from paddocks. The longest activity was grazing, followed by rumination and other activities, and the period from 6 to 10 h showed the longest grazing.In the other periods, the animals in the 35-cm treatment grazed less when compared to those ofthe other treatments. Rumination in all treatments was more significant in the period from 14 to 18 h, but the animals in the 45-cm treatment spent more time doing this activity, which gave them a higher time of rumination of the food bolus, as well as ruminating chews. The bite rate was higher for the 25-cm treatment, followed by the 45 and 35-cm treatments, respectively.

ABSTRACT We evaluated the technical feasibility of purified glycerin inclusion in balanced diets of broiler chickens treated from 1 to 42 days of age. A total of 240 broiler chickens were distributed in a completely randomized design into four treatments (0, 2, 4, and 6% purified glycerin inclusion), with six replicates of 10 broilers each. We evaluated productive performance (at 7, 21, and 42 days), edible viscera (heart, liver, and gizzard), carcass yield and cuts, color, chemical and physical composition, as well as protein and fat deposition in the breast muscle. Dietary inclusion of purified glycerin reduced feed conversion and increased feed intake, weight gain, and weight at seven days. From 1 to 21 days, there was a decrease in feed conversion and a linear increase in weight gain, with no effect on feed intake. Considering the total experimental period, increasing glycerin levels increased weight gain and weight at 42 days, with no effects on feed conversion or feed intake. Similarly, there was no effect on carcass and cut yields, liver and gizzard yields, and weight or length of the intestine, while heart yield was decreased. There was a linear increase in crude protein, ether extract, protein, and fat deposition and a reduction in moisture percentages, with no effect on ash content. Purified glycerin levels did not affect a*, b*, L*, pH, temperature, shear force, or weight loss by cooking in breast meat. The dietary inclusion of purified glycerin of up to 6% proved to be technically feasible in the diets of broilers from 1 to 42 days.

RESUMO Foram avaliados o desempenho e a cor da pele de frangos de corte de crescimento lento no período de 30 a 90 dias, alimentados com dietas com diferentes inclusões de bagaço de mandioca e colorífico de urucum. 308 frangos de corte de crescimento lento foram utilizados em um delineamento experimental inteiramente casualizado, em esquema fatorial com tratamento adicional 3 X 2 + 1, sendo três níveis de colorífico de urucum como agente pigmentante (1%, 2% e 3%), dois níveis de bagaço de mandioca (10% e 20%) e um tratamento adicional (dieta de controle), totalizando sete tratamentos, quatro repetições e 11 frangos de corte por unidade experimental. O consumo de ração e a conversão alimentar foram influenciados pelos tratamentos, com interação. O ganho de peso e o peso final foram influenciados pelos tratamentos (p<0,001) e os melhores resultados foram encontrados para a inclusão de 10% de bagaço de mandioca e 2% de colorífico de urucum. Não houve efeito dos tratamento e nenhuma interação sobre o rendimento da carcaça. Os parâmetros de cor L *, a * e b * não foram influenciados pelos tratamentos. É recomendável a inclusão de bagaço de mandioca a 10% e 1% de colorífico de urucum para frangos de crescimento lento de 30 a 90 dias de idade. No entanto, o uso desses ingredientes provou ser economicamente inviável.

SUMMARY The performance and breast skin color of slow-growing broilers from 30 to 90 days old fed diets with different inclusions of cassava bagasse and annatto colorific were evaluated. 308 slow-growing broilers were used in a completely randomized experimental design, in a factorial scheme with an additional treatment 3 X 2 + 1, with three levels of annatto colorific as a pigmentant agent (1%, 2% and 3%), two levels of cassava bagasse (10% and 20%) and an additional treatment (control diet), totaling seven treatments, four replicates and 11 broilers per experimental unit. Feed intake and feed conversion were affected by treatments, with interaction. The weight gain and final weight were influenced by the treatments and the best results were found for the inclusion of 10% cassava bagasse and 2% annatto colorific. There was no effect of treatment and no interaction on carcass yield. The color parameters L*, a* and b* were not influenced by treatments. The inclusion of 10% cassava bagasse and 1% annatto colorific for slow-growing broilers from 30 to 90 days of age is recommended. However, the use of these ingredients proved to be economically unfeasible.

RESUMO. Objetivou-se avaliar o efeito da inclusão do propilenoglicol na água de ovelhas durante a lactação sobre os metabólitos proteicos e minerais de suas crias. Foram avaliados 24 cordeiros (as), filhos (as) de ovelhas que receberam níveis de propilenoglicol (0; 1,5; 3,0 e 4,5%) na água. As ovelhas foram distribuídas em delineamento inteiramente casualizado em esquema de parcela subdividida. Não houve efeito de interação entre a idade dos cordeiros (a)s e a quantidade(s) de propilenoglicol oferecido para as mães na concentração dos metabólitos proteicos e minerais dos cordeiros. A concentração de proteínas totais, globulinas, relação albumina:globulinas, ácido úrico e creatinina nos cordeiros não foi afetada pela inclusão de propilenoglicol na água das matrizes. A concentração de ureia e magnésio nos cordeiros apresentou resposta quadrática em função da inclusão de propilenoglicol na dieta das ovelhas, sendo que para a concentração de albumina houve resposta linear. A inclusão de propilenoglicol na dieta das ovelhas e a idade dos cordeiros alteram a concentração dos metabólitos proteicos e minerais nas crias. Contudo, a utilização do propilenoglicol na alimentação de ovelhas lactantes não proporciona efeitos negativos nos parâmetros sanguíneos dos cordeiros, o que é evidenciado pela ausência de déficit nutricional (proteína e minerais) nos cordeiros lactentes.

ABSTRACT. The aim of this study was to assess the effect of propylene glycol (PG) added to the water sheep drank during lactation on protein and mineral metabolites of their suckling lambs. We assessed 24 lambs born to sheep fed levels of propylene glycol in the water (0; 1.5; 3.0 and 4.5%). The sheep were subdivided according to a completely randomized design, in a split-plot scheme. There was no interaction effect between lamb age and amount of PG provided to the sheep on the concentration of protein and mineral metabolites of the lambs. The concentration of total protein, globulin, and albumin: globulin ratio, uric acid and creatinine in the lambs was not affected by the inclusion of PG (p > 0.05). The concentration of urea and magnesium in the lambs presented a quadratic response as a function of the addition of PG; there was linear response for albumin concentration. The addition of PG to the sheep’s diet and the lambs’ age affect the concentration of protein and mineral metabolites in the lambs. However, using PG to feed lactating sheep does not have negative effects on the lambs’ blood parameters, as evidenced by the absence of nutritional deficiency (protein and minerals) in the suckling lambs.

ABSTRACT The objective of the study was to assess the effects of including 0, 79.8, 159.8, and 240.0 g kg-1 crude glycerin in the total diet dry matter on the 84 days feedlot performance, nutrient digestibility, blood parameters, and carcass characteristics of crossbred dairy steers. Experimental diets were composed of 98.5 g kg-1 of sorghum silage and 901.5 g kg-1 of concentrate. Twenty-four crossbred dairy steers (337.3±39.8 kg body weight and 15 months of age) were distributed in a completely randomized design with four treatments and six replicates. The intake and digestibility of the dry matter and nutrients were not altered by including crude glycerin in the diet. Crude glycerol levels did not affect the final weight (430.2 kg), daily weight gain (1.38 kg day-1), total weight gain (97.2 kg), hot carcass weight (218.9 kg), cold carcass weight (215.2 kg), hot carcass yield (0.50 kg 100 kg-1 BW), longissimus dorsi area (62.86 cm²), subcutaneous fat thickness (4.05 mm), and carcass physical composition. Concentrations of serum glucose, triglycerides, total cholesterol, high-density lipoprotein cholesterol, and creatinine were not altered by including crude glycerin in the diet. Crude glycerin can be added to high concentrate diet up to 240 g kg-1 without changing the animal performance, apparent digestibility of nutrients, the main carcass characteristics, and blood parameters of finishing crossbred dairy steers.

RESUMO Objetivou-se neste trabalho avaliar o efeito da gravidade específica de ovos de matrizes pesadas com diferentes idades no rendimento de incubação e no peso dos pintos pós-eclosão. Foram utilizados 3.072 ovos oriundos de dois lotes de matrizes pesadas, linhagem Cobb – 500®. Os ovos foram distribuídos em delineamento experimental inteiramente casualizado, em esquema fatorial 2x4, com duas idades de matrizes (53 e 64 semanas) e quatro diferentes densidades (1.070, 1.075, 1.080, 1.085), totalizando oito tratamentos e quatro repetições (com 96 ovos por unidade experimental). As variáveis avaliadas foram o peso do ovo (g), a taxa de eclosão (%), a taxa de fertilidade (%), a perda de peso dos ovos durante o período de incubação (%) e a relação do peso dos pintos/peso dos ovos (%). Os resultados foram submetidos à análise de variância, sendo que o efeito das densidades foi avaliado por meio de regressão polinomial e o efeito da idade das matrizes pelo teste F, ao nível de 5% de probabilidade. As perdas de peso dos ovos, exceto para as densidades de 1.075 e 1.085, oriundos de matrizes com 53 e 64 semanas de idade, respectivamente, apresentaram-se dentro dos valores recomendados na literatura. O peso do pinto ao nascer foi proporcional ao peso do ovo, representando em média 68% e sem diferenças entre a idade das matrizes e as diferentes densidades. A idade da matriz exerceu influência no rendimento de incubação, sendo as maiores taxas de fertilidade e eclosão total (p<0,05) obtida pelos ovos oriundos de matrizes com 53 semanas de idade.

SUMMARY The objective of this work was to evaluate the effect of specific gravity of eggs from broiler breeders of different ages in the yield of incubation and the weight of post-hatch chicks. Were used 3.072 eggs from two batches of broiler breeders, Cobb - 500®. The eggs were distributed a completely randomized design in a 2x4 factorial design with two broiler breeder ages (53 and 64 weeks) and four different egg densities (1.070, 1.075, 1.080, 1.085), totaling eight treatments and four replications (with 96 eggs per experimental unit). The evaluated variables were the egg weight (g), the hatching rate (%), the fertility rate (%), the weight loss of eggs during the incubation period (%) and the ratio of the weight of the chicks/egg weight (%). The results were submitted to analysis of variance, being that the effect of density was assessed by polynomial regression and the age effect of breeders by F test at 5% probability. Weight losses of eggs, except for the densities of 1,075 and 1,085, from breeders with 53 and 64 weeks of age, respectively, were within the values recommended in the literature. The chick weight was proportional to the weight of the egg, representing on average 68% and no differences between age and density of broiler breeders. The age of the breeders exerted influence on the yield of incubation, and the best results (p<0.05) obtained by eggs from breeders with 53 weeks of age.