Effects of a monocomponent protease from Bacillus licheniformis on broiler performance, digestibility, and carcass yield

Two experiments were carried out to evaluate the effects of protease addition to the diet of broilers at a higher level (1× or 2×) than the nutritional value proposed for the enzyme. The first experiment, 1280 day-old chicks (Cobb500®) were randomly allocated (randomized block design, 2×2+1 factorial arrangement), five treatments, eight replicates containing 32 birds/replicate. Treatments consisted: control diet without protease (CD); CD + 1× nutritional value of the enzyme (CDM1); CD + 2× nutritional value of the enzyme (CDM2); CDM1 + protease; and CDM2 + protease. The experimental period was 42 days. The mean weight (AFW), feed intake (FI), weight gain (WG), feed conversion, and carcass yield were evaluated. Significant differences were observed for AFW, WG, FI, abdominal fat yield, and feet percentage in the carcass. In the second experiment, 120 Cobb500® chicks at 14 days of age were allotted in a completely randomized design, 2×2+1 factorial arrangement, five treatments, six replicates with four birds/replicate. The treatments were consistent with the first experiment. Significant improvements in the nitrogen balance were observed for the broilers that received protease. The use of the enzyme tested is recommended with the recommended nutritional matrix, improving the zootechnical indices of broilers.

Standardized ileal digestibility of amino acids of protein sources associated with exogenous enzymes for broilers

Objective

Two experiments were conducted to evaluate the effect of enzyme complex (EC) on the standardized ileal digestibility (SID) of amino acids (AA) in corn gluten meal (60%) (CGM), soy protein concentrate (SPC), dried bovine plasma (DBP) and poultry offal meal (POM). Experiments I and II were conducted with broilers in the pre-starter (1 to 7 days of age) and starter (1 to 21 days of age) phases, respectively.

Methods

The treatments consisted of a protein-free diet (PFD) containing feedstuffs either supplemented with EC (xylanase, amylase, and protease) or not. In Experiment I, a total of 360 one-day-old male Cobb-500® broiler chicks were randomly housed in 45 pens, resulting in five replicates with eight birds each, totalizing eight treatments and one PFD group. In Experiment II a total of 270 one-day-old male Cobb-500® broiler chicks were randomly housed in 45 pens, resulting in five replicates with six birds each, totalizing eight treatments and one PFD group. The PFD groups were used to assess the endogenous AA losses. The birds were slaughtered to collect the ileal content.

Results

In the pre-starter phase, the SID of arginine, branched chain-aminoacids, glycine, serine, aspartate, and glutamic acid increased with EC addition. The EC improved the SID of arginine and glutamic acid of CGM; the SID of valine and cystine of SPC; the SID of leucine, glycine, and aspartate of POM and the SID of isoleucine of DBP. In the starter phase, the SID of isoleucine, phenylalanine and glycine increased in EC-supplemented diets. The EC improved the SID of isoleucine of DBP; the SID of phenylalanine of CGM and POM. The SID of AA of SPC was not influenced by the EC.

Conclusion

The addition of an enzyme complex to broiler pre-starter and starter diets is efficient in increasing the SID of AA on SPC, POM and DBP.

Blood biochemical parameters and organs development of brown layers fed reduced dietary protein levels in two rearing systems

Objective

An experiment was conducted to evaluate the effect of different levels of crude protein (CP) and two rearing systems (cage and floor), on blood parameters and digestive and reproductive organ development of brown laying hens.

Methods

A total of 400 Hisex Brown laying hens between 30 and 45 weeks of age were distributed in a completely randomized design and a 2×4 factorial arrangement, with main effects including two rearing systems (cage and floor) and levels of CP (140, 150, 160, and 180 g/kg), in a total of eight treatments and five replicates of 10 birds each with initial body weight of 1,877 g (laying hen in cage) and 1,866 g (laying hens in floor). The parameters evaluated were plasma total protein, albumin, uric acid, total cholesterol, relative weights of oviduct, abdominal fat, liver, gizzard, crest and dewlap, length of small intestine and oviduct.

Results

The blood parameters were similar in birds reared in cage and floor systems. The birds reared on the floor showed greater small intestine and oviduct weight (%) and lower liver and pancreas weight (%). A significant interaction was observed between factors for the relative gizzard, crest and dewlap weight, serum protein, uric acid, and total cholesterol (P<0.05). The diets with 140 g/kg CP resulted in lower serum protein and lower cholesterol in birds reared in floor system, while birds reared in cage system showed no effect of CP on both parameters. Birds reared in cage and fed with 140 and 150 g/kg CP presented lower uric acid. The group of birds reared in floor system fed 180 g/kg had greater uric acid.

Conclusion

The dietary protein level can be reduced up to 140 g/kg for Hisex Brown hens (30 to 45 weeks of age) without an important effect on metabolic profile and organ development in both rearing systems.

The transfer of amino acids and minerals to the egg yolk and to the yolk sac of their progeny is affected by breeder age

This study aimed to assess the effects of breeder age on egg quality and amino acid and mineral transfer to the egg yolk and yolk sac of newly hatched chicks. Three ages (32, 42 and 52 weeks) of the same commercial flock of Hubbard breeders were studied. A total of 465 eggs were used for each age, with 60 being used for determining egg quality and amino acid and mineral content of yolk, and 405 for incubation period to obtain and evaluate the yolk sac of chicks. Breeders aged 52 weeks had heavier eggs and a higher percentage of yolk (p < 0.05), whereas 32-week-old breeders had higher eggshell percentage and thickness (p < 0.05). The percentage of protein deposited in egg yolk for 52-week-old breeders was higher than that for 32- and 42-week-old breeders (p < 0.05). Percentages of methionine, cysteine, met + cysteine, lysine, threonine, tryptophan, arginine and isoleucine in egg yolk for 32-week-old breeders were higher than that for 42- and 52-week-old breeders (p < 0.05). The transfer from breeder of phosphorus, potassium, calcium, magnesium, copper, iron, manganese and zinc to the yolk of eggs from 32-week-old breeders was greater than that for eggs from 42- and 52-week-old breeders (p < 0.05). Chicks from 32-week-old breeders had greater deposition of phosphorus and calcium in the yolk sac (p < 0.05). Breeder age did not affect the deposition of potassium, magnesium, copper, iron, manganese and zinc in the yolk sac of newly hatch chicks (p > 0.05). It can, however, be concluded that younger breeders deposit more amino acids and minerals in egg yolk, while embryos of older breeders seem to use the nutrients present in the yolk more efficiently during embryonic development.

Supplementation of sucupira oil in broiler diets

ABSTRACT The objective of the present study was to ascertain the effect of sucupira oil in diets of broilers on gut development, dry matter and nitrogen metabolizability and broilers performance. A total of 350 one-d-old, male, Cobb500® broiler were allotted in seven treatments with five replicates, totaling 35 experimental units with 10 birds each. The dietary treatments consisted of a negative control diet, four diets with different levels of sucupira oil (100; 500; 900 and 1,300 mg/kg), diet with mannanoligosaccharide and control diet with antibiotic. The inclusion of 900 and 1,300 mg of sucupira oil impaired gut development and metabolizability of nutrients (P<0.05). The inclusion of 100 or 500 mg of sucupira oil in broiler feed was similar to negative control, MOS and antibiotic treatments for performance variables (all phases studied) and also for nutrient metabolizability (P<0.05). It can be concluded that high levels of sucupira oil is not recommended in broilers diet.

Feeding dihydroquercetin and vitamin E to broiler chickens reared at standard and high ambient temperatures

The use of natural antioxidants, in particular polyphenols such as dihydroquercetin (DHQ), in animal nutrition has recently increased in popularity. This may partly be due to the risk of increased incidences of heat stress associated with raising livestock in warmer ambient temperatures, facilitated by global warming, reducing antioxidant capacity. The current research demonstrates the effect of dietary DHQ, vitaminEand standard or high ambient temperatures on growth performance, energy and nutrient metabolism, gastrointestinal tract (GIT) development, jejunal villus morphometry and antioxidant status in broiler chickens. Each of the four experimental diets was fed to 16 pens of five birds, which were allocated to four rooms (four pens in each room). The temperature in two rooms was maintained at aconstant 35°C (high temperature; HT), and the temperature in the other two rooms was gradually reduced from 27°C at 7 dof age to 22°C at 20 dof age (standard temperature; ST). Rearing birds at HT reduced feed intake, weight gain, weight of small intestine, total GIT, liver, spleen, heart, villus height, villus surface area and lowered blood glutationperoxidase (GSH-Px). Dietary DHQ increased blood GSH-Px and total antioxidant status, increased heart weight and reduced caecal size. When fed separately, DHQ and vitamin E improved hepatic vitamin E concentration. Feeding vitamin Eincreased spleen and liver weights. When fed together, DHQ and vitamin Ereduced villus height, villus height to crypt depth ratio and villus surface area. Temperature and antioxidants did not affect energy and nutrient metabolism. There were no effects of dietary antioxidants on growth performance of broiler chickens and there were no mortalities. At present, it is unclear if feeding antioxidants (in particular DHQ) at different levels, using different dietary formulations, and rearing birds under arange of environmental conditions may be effective at enhancing production performance and bird health in hot ambient climates.

ASPECTOS REPRODUTIVOS E DESEMPENHO DE DIFERENTES LINHAGENS DE MATRIZES DE CODORNAS JAPONESAS

Resumo Objetivou-se avaliar parâmetros reprodutivos e o desempenho de diferentes grupos genéticos de codornas japonesas com diferentes pesos iniciais de produção. O delineamento experimental utilizado para os dados de desempenho zootécnico das aves foi inteiramente casualizado, com esquema fatorial 3 x 2 (três linhagens: UEM1, UEM2 e Comercial (COM), e duas classes de peso: leves e pesadas), totalizando seis tratamentos, com oito repetições cada, portanto 48 parcelas. Cada parcela continha oito aves (dois machos e seis fêmeas), num total de 384 codornas. Foi analisado: a idade ao primeiro ovo, idade aos 50% de produção, idade de pico de produção e persistência de pico em semanas. O desempenho foi analisado por meio da produção de ovos, consumo de ração, conversão alimentar e mortalidade. Ainda, foi estudado a produção de ovos incubáveis. A linhagem COM apresentou maior peso vivo às seis semanas de idade, sendo UEM 1 e UEM 2 semelhantes entre si. Para a idade ao primeiro ovo, o grupo COM se equiparou UEM 1, sendo a UEM 2 foi mais tardia. Já para a variável idade aos 50% de produção de ovos a linhagem COM apresentou-se mais precoce em relação às demais linhagens. Não foi observado efeito do peso das codornas sobre a idade do primeiro ovo. Não houve efeito de interação entre linhagem e peso inicial das aves para nenhuma das variáveis de desempenho reprodutivo estudadas. Ainda, pode-se observar que não houve diferença entre os grupos genéticos ou peso corporal inicial para produção de ovos, quando considerado o período de 6 a 26 semanas de idade. Não houve diferença entre os grupos genéticos para consumo de ração durante o período de 20 semanas estudado e não houve efeito do peso inicial de produção sobre essa variável (P>0,05). A conversão alimentar kg/dz, melhorou pelos grupos das linhagens UEM 1 e UEM 2. Para a peso de ovos incubáveis o grupo comercial apresentou maior peso. Foi possível concluir que o melhoramento genético de codornas japonesas de postura necessita aprimoramento e que linhagem comercial não melhorada pode apresentar resultados semelhantes às linhagens melhoradas.

FRANGOS DESAFIADOS EXPERIMENTALMENTE COM Salmonella enterica SOROVAR ENTERITIDIS E Eimeria tenella E TRATADOS COM ÁCIDOS ORGÂNICOS

Resumo Foi avaliado um composto comercial de ácidos orgânicos, adicionado à ração, no controle da Salmonella de frangos de corte desafiados com Salmonella Enteritidis e Salmonella Enteritidis associadas à Eimeria tenella. Foram utilizados 504 pintos de um dia, fêmeas, da linhagem Hubbard®, sendo o delineamento inteiramente casualizado em esquema fatorial 2x3, totalizando seis tratamentos com seis repetições e 14 aves a unidade experimental. Foi analisado o pH intestinal, o escore de lesão dos cecos, contagem de oocistos fecais e a presença de salmonela no baço e tonsilas cecais das aves. Aves desafiadas com S. Enteritidis que receberam ácidos apresentaram menor frequência de isolamento da bactéria nos órgãos linfoides analisados. Assim como apresentaram redução no número de oocistos de E. tenella nas excretas coletadas diretamente na bandeja e redução dos escores de lesão intestinal provocadas pela infecção por Eimeria tenella. Os ácidos orgânicos promoveram benefício à saúde intestinal dos frangos de corte com reflexos positivos no controle da Salmonella Enteritidis juntamente com a Eimeria tenella.

<b>Supplementation of extract of <i>Lafoensia pacari</i> in the diet of semi heavy laying hens

 It was intended to evaluate the supplementation of Lafoensia pacari standardized in tannins extract in the diet of laying hens on the performance, internal and external quality of eggs and metabolism of the feed nutrients. A total of 168 Isa Brown laying hens, aged 24 weeks, with the mean weight of 2.6 kg and the mean posture rate of 87% were used during 4 periods of 28 days each. The treatments consisted of Halquinol performance-enhancing antibiotic, Mannanoligosaccharide (MOS) prebiotic and three levels of pacari extract – 1,000, 2,000 and 3,000 mg kg-1of feed. The experimental design was completely randomized, with six treatments and seven replicates of four hens each. The pacari standardized in tannin extract presented a percentage of albumen and an egg weight similar to the antibiotic (p < 0.04). The supplementation with the extract improved the shell quality, verified by the specific gravity (p < 0.03) and promoted the metabolizability of ether extract similar to antibiotic and MOS (p < 0.04), allowing its indication as a phytogenic additive. 

HISTOMORFOMETRIA DE ORGÃOS LINFOIDES E DESENVOLVIMENTO INTESTINAL DE PINTOS DE CORTE ORIGINADOS DE MATRIZES COM DIFERENTES IDADES E SUBMETIDOS AO ESTRESSE POR CALOR NA INCUBAÇÃO

Resumo: Objetivou-se avaliar o efeito da idade da matriz e da variação da temperatura de incubação sobre a qualidade do pinto neonato. O delineamento foi inteiramente casualizado em esquema fatorial 3x2 (três idades x duas temperaturas de incubação). Foram incubados 720 ovos, provenientes de matrizes com diferentes idades (30, 42 ou 64 semanas). A temperatura da máquina de incubar para os grupos controle foi mantida constante (37,5 ºC) e para os tratamentos com estresse por calor foi aplicada uma temperatura de 39,0 ºC por 6h durante o período de 10 a 18 dias de incubação. Cinco pintos por tratamento foram sacrificados para coletas de órgãos e realizada a histomorfometria intestinal, de baço e bursa. Os dados foram submetidos a análise de variância e foi utilizado o teste de Tukey (5%). A área dos folículos da bursa foi maior nos pintos oriundos de matrizes mais velhas quando os ovos foram incubados em temperatura ideal. A temperatura de 39,0 ºC estimulou o desenvolvimento intestinal. A variação na temperatura de incubação prejudicou a qualidade de pintos, sobretudo para pintos originados de matrizes jovens. Pintos oriundos de matrizes velhas apresentaram melhor resposta imune e desenvolvimento intestinal, independentemente da variação da temperatura de incubação.

Adição de óleos de copaíba (Copaifera langisdorffii) e sucupira (Pterodon emarginatus) na alimentação de poedeiras: estabilidade lipídica de gema de ovos armazenados em diferentes temperaturas

<p>O objetivo deste trabalho foi avaliar a atividade antioxidante da adição de óleos de copaíba (CP) e sucupira (SC) na alimentação de poedeiras sobre a oxidação lipídica de ovos <em>in natura</em> armazenados em temperatura ambiente (TA) por 30 dias e sob refrigeração (R) a 4ºC por 60 dias, e de gemas cozidas mantidas sob R por 30 dias. As poedeiras foram alimentadas com ração isoproteica (15% PB) e isoenergética (2900 kcal kg^-1) à base de milho e farelo de soja, com inclusão de óleo de <em>Copaifera langsdorffii </em>(CP) nas proporções de 0,03; 0,06 e 0,09% ou de <em>Pterodon emarginatus </em>(SC) nas proporções de 0,03 e 0,06%, mais um controle negativo (CN). Foram coletados 667 ovos às 37 semanas de idade e distribuídos aleatoriamente nas diferentes condições de armazenamento (TA ou R). A oxidação dos lipídios de ovos <em>in natura</em> foi quantificada em quadruplicata e das gemas cozidas em duplicata, utilizando-se “pool” de 3 gemas/tratamento para as análises de TBARS (thiobarbituric acid reactive substances). Os dados foram avaliados adotando um modelo misto e as médias foram comparadas pelo teste de Tukey em 5% de nível de significância e o período de armazenamento foi considerado como um fator longitudinal, variando de cinco tempos no experimento com gemas cozidas, e nos ovos <em>in natura</em> sob R e em TA (0 a 30 dias), até nove tempos sob R (0 a 60 dias). Foi observado que a adição de óleo de CP e SC não reduziu os valores de TBARS em ovos <em>in natura</em> armazenados em TA e sob R em relação ao CN. No armazenamento de gemas cozidas, a inclusão CP (0,03 e 0,06%) protegeu os lipídios até os 21 dias, mas apresentou efeito pró-oxidante quando suplementado a 0,09%. Concluiu-se que a inclusão de até 0,06% de óleorresina de CP nas rações de poedeiras pode proteger os lipídios da gema cozida contra a oxidação durante o armazenamento refrigerado por até 21 dias. <strong></strong></p><br /><strong></strong>

CHEMICAL AND ENERGETIC CONTENT OF CORN BEFORE AND AFTER PRE-CLEANING

The poultry industry normally has little control over the raw material that arrives at the processing plant. This experiment aimed to evaluate chemical and energetic quality of corn obtained in a feed mill before and after pre-cleaning. Twenty samples of 30 kg of corn each were taken from trucks delivering corn to the mill. The trucks were then unloaded and the material passed through a pre-cleaning process when another sample was taken. Samples were graded and physical properties evaluated: density (g/L), grain percentages of foreign material, impurities, fragments, broken, soft, insect damaged, fire-burnt, fermented, damaged, cracked and fine particles, as well as chemical composition analysis: Apparent metabolizable energy for poultry (AME), ether extract (EE), crude fiber (CF), starch (STA), water activity (WA), crude protein (CP), digestible and total lysine, methionine, cystine, threonine, tryptophan, valine, isoleucine, leucine, phenylalanine, histidine and arginine. The experiment was a randomized design with two treatments (before and after pre-cleaning) and twenty replications. Data was analyzed using SAS ® and treatment differences obtained using F test. Correlations and principal components were calculated. There was a decrease in density after the pre-cleaning process, which was probably due to the removal of earth and stones rather than grain and its fractions. Significant increases were found for insect damage, fermented and damaged grain while fire-burn was significantly reduced after the pre-cleaning process. Starch increased after pre-cleaning which is a result of contaminants that normally are poor in this carbohydrate, but fiber levels increased too. Apparent metabolizable energy, aminoacids, digestible (P<0.05) and total (P<0.05) histidine, total lysine and methionine (P<0.1) levels were reduced after pre-cleaning. Density was higher when there were fewer impurities such as straw, husk or small grains. Broken corn was positively correlated (P<0.05) with foreign material (0.63) and fragments (0.76), while proportion of damaged corn was positively correlated with foreign material (0.68), fragments (0.58) and broken corn (0.83). In this study, even in samples classified as excellent quality before pre-cleaning, the pre-cleaning process was effective in reducing humidity and water activity which helps control the growth of fungi or other microorganisms. Starch and fiber levels increased after pre-cleaning while apparent metabolizable energy levels was not improved by pre-cleaning.

Qualidade bacteriológica de ovos contaminados com Pseudomonas aeruginosa e armazenados em temperatura ambiente ou refrigerados

Objetivou-se verificar o efeito da sanitização e da temperatura de armazenamento sobre a qualidade bacteriológica de ovos contaminados experimentalmente com Pseudomonas aeruginosa. Foram utilizados 240 ovos brancos em esquema fatorial 2 x 2 (lavados ou não e refrigerados ou não). Os ovos foram sanitizados com água quente contendo clorhexidina 20% e teor ativo 8% de cloro. Após a sanitização, foram contaminados com 1,5 x 10(5) unidades formadoras de colônia (UFCs) de Pseudomonas aeruginosa/mL de solução e armazenados a 5 ºC ou 25 ºC por 30 dias. A cada dez dias foram realizadas análises bacteriológicas e contagens de Pseudomonas aeruginosa na casca e conteúdo. Foi realizada análise de variância e as médias comparadas pelo teste de Tukey. Pseudomonas aeruginosa foi isolada da casca e do conteúdo em todos os ovos, independentemente dos tratamentos. No entanto, quando os ovos foram sanitizados e armazenados a 5 ºC apresentaram menor contagem bacteriana na casca e no conteúdo. Houve alta correlação entre Pseudomonas aeruginosa presente na casca com a presença no conteúdo do ovo quando os ovos não foram sanitizados e resfriados. Concluiu-se que para reduzir o crescimento bacteriano de Pseudomonas aeruginosa, os ovos devem ser sanitizados e mantidos a 5 ºC durante o armazenamento de 30 dias.

Performance and intestinal characteristics of broiler chicken fed diet with glutamine in the diet without anticoccidials agents

Five hundred commercial male Cobb broilers were allotted in a randomized blocks design with five treatments, four replicates and 25 chicks per experimental unit in order to evaluate the effects of adding L-glutamine to the diet with no anticoccidial agents and growth promoters. Experimental diets contained L-glutamine at different levels (0.0; 5.0; 10.0; 15.0 or 20.0g/kg), through the experimental period. Experiment was conducted with broiler chicken from 1 to 42 days old. The parameters evaluated were feed intake, feed conversion ratio, body weight gain, mortality, digestibility coefficients of dry matter, crude protein and ether extract, carcass yield and intestinal mucosa structure of small intestine. The data obtained were submitted to polynomial regression analysis. Means were compared using Tukey test.Was considered a type I error set at P < 0.05. The level of L-glutamine in the diet influenced feed conversion ratio of broilers at 1-7 days old, which was improved at 10.0g/kgL glutamine. Carcass yield and digestibility coefficients of the diet were not affected by the levels of glutamine in the diet. Adding L-glutamine influenced crypt depth in small intestine of broilers at 18 and 42 days old. It is recommended the addition of 10.0g/kg L-glutamine to the pre-started diet.

Balanços nutricionais e excreção de nutrientes para frangos alimentados com dietas contendo fitase do 14.o ao 24.o dias de idade

Objetivou-se com este estudo avaliar o efeito da redução de nutrientes e energia suplementada ou não com fitase para frango de corte na fase 14 a 24 dias de idade no consumo, excreção e balanço de nitrogênio, de cálcio e de fósforo. Foram distribuídos 392 frangos de corte em delineamento inteiramente casualizado, utilizando-se arranjo fatorial 3 x 2 + 1 que consistiram de nível reduzido de cálcio e fósforo; níveis reduzidos de aminoácidos e energia; níveis reduzidos cálcio, fósforo, aminoácidos e energia x com e sem enzima + controle positivo, totalizando sete tratamentos com oito repetições de sete aves por unidade experimental. Nas dietas com fitase utilizou-se 500 FTU de fitase/kg de ração. Os dados foram submetidos à análise de variância e as médias comparadas por contrastes ortogonais através do teste F. Os resultados demonstram que a enzima fitase utilizada permitiu diminuir a quantidade de nutriente e energia das rações, proporcionando redução de 21,34% na excreção de cálcio e balanço de cálcio de 20,16%. Similarmente, reduções das quantidades de excreção de nitrogênio em 7,56% e fósforo em 21,34%, diminuindo a excreção desses nutrientes e aumentando o balanço de nitrogênio e fósforo em 9,41 e 33,94% em média, respectivamente.

Efeitos da lactulose na saúde gastrointestinal de frangos de corte experimentalmente inoculados com Salmonella entérica sorovar Typhimurium

Avaliaram-se os efeitos da lactulose na saúde gastrointestinal de frangos de corte pela aferição do pH e enumeração de unidades formadoras de colônias (UFCs) de Salmonella Typhimurium e Escherichia coli no inglúvio e ceco de aves inoculadas experimentalmente, via oral, na dose de 5,0 X 102 UFC /0,5mL com Salmonella Typhimurium. O delineamento adotado foi o inteiramente casualizado, utilizando-se 630 pintos, machos, os quais foram distribuídos em seis tratamentos, com sete repetições e 15 aves por unidade experimental. O tratamento 1: grupo controle (placebo); tratamento 2: grupo que recebeu somente a lactulose na água; tratamento 3: grupo que recebeu somente Salmonella Typhimurium; tratamento 4: grupo que recebeu a lactulose e Salmonella Typhimurium simultaneamente no primeiro dia de vida [L (1d) + ST (1d)]; tratamento 5: grupo que recebeu a lactulose 48 horas antes de serem inoculadas com Salmonella Typhimurium [L (1d) + ST (48h)] e tratamento 6: grupo que foi inoculado com Salmonella Typhimurium no primeiro dia e 48 horas depois receberam a lactulose [ST (1d) + L (48h)]. Aos dias sete, 14, 21 e 28 uma ave por parcela foi sacrificada e os conteúdos do inglúvio e do ceco foram coletados para a aferição do pH e contagem de Salmonella Typhimurium e Escherichia coli. Constatou-se que a lactulose determinou redução nos valores (P<0,05) de pH nos conteúdos do trato digestório aos sete dias de vida, e esta redução se manteve até 28 dias somente para o inglúvio nos tratamentos que receberam a lactulose, independente do período de inoculação do patógeno. Verificou-se, também, que a lactulose reduziu (P<0,05) as UFCs de Escherichia coli e de Salmonella Typhimurium no inglúvio aos 21 e 28 dias de vida nos tratamentos em que se administrou a lactulose antes do patógeno. Pode-se concluir que a lactulose altera os valores de pH do inglúvio e reduza colonização de Salmonella Typhimurium no ceco e as UFCs de Escherichia coli no inglúvio em todo o período experimental.

Fertility and hatchability of eggs laid in the pullet-to-breeder transition period and in the initial production period

The initial eggs produced by broiler breeder hens are relatively small compared with later in the production cycle. An evaluation of indices related to hatchability is required when these eggs are to be used for the production of broiler chicks. Two experiments were conducted to evaluate characteristics related to the hatchability of eggs from pullet-to-breeder transition phase, at 25 and 27 weeks of age, and from the peak of production period and five weeks later, at 32 and 37 weeks of age. Eggs from birds 25 weeks had a lesser fertility in Experiment 1. Mortality occurred unevenly in early (1-5 days), middle (6-17 days) and late (18-21 days) incubation, and greater mortality was observed after the internal membrane was ruptured. The younger the hen, the lighter the egg, chick, and shell, and the longer the time required to complete the hatching process. In Experiment 2, greater mortalities were observed at the early period (1-5 days) and after "pipping" of the internal and external membranes. Embryos from heavy eggs of breeder hens 37 weeks of age took less time to complete the hatching process. Results indicated the larger the egg, the heavier the chick and shell, and the lesser the shell percentage. As breeder age advanced, characteristics related to egg fertility and hatchability improved.