RESUMO
The objectives of this study were to describe alterations that age and dietary inclusion of direct-fed microbial (DFM) Bacillus subtilis (BS) and a specific essential oil (EO) blend (carvacrol, cinnamaldehyde, cineol, and pepper extract) causes in the activity of digestive enzymes (maltase: MALT; aminopeptidase-N: APN; intestinal alkaline phosphate: IAP) and expression patterns of genes related to transport (oligopeptide transporter gene: SLC15A1; Na+-dependent glucose and galactose transporter gene: SLC5A1; Na+-independent glucose, galactose, and fructose transporter gene: SLC2A2; ATPase, Na+/K+ transporting gene: ATP1A1) and digestion (aminopeptidase-N gene: ANPEP; maltase-glucoamylase gene: MGAM; Sucrase-isomaltase gene: SI) of carbohydrates and proteins in the small intestine of broilers. Also, the objective was to analyze if growth performance of broilers is affected by supplementation (BS and EO blend). Day-old male broiler chicks (n = 1,320) were assigned to 5 treatments. Diets included a basal diet (BD) as a negative control (CON); experimental diets were BD + BS; BD + BS + EO; BD + EO; BD + antibiotic growth promoter (AGP) avilamycin was the positive control. Performance was evaluated between 1 to 42 d. Transcript abundance of transport-related genes and digestion-related genes were assayed by RT-qPCR and determined at d 7, 21, and 42. MALT-, APN-, and IAP-specific activities were determined at d 7, 21, and 42. Broilers fed BS had greater SLC15A1 mRNA abundance compared to CON, while EO and AGP were related to higher activities of IAP and APN. Analysis over time revealed higher abundance of MGAM, SLC2A2, SLC15A1, SLC5A1 and SI mRNA at d 42 when compared to d 7. Activity of IAP decreased after d 7 and activity of MALT increased with age. The current study suggests that age had effect over carbohydrate and protein transport and carbohydrate digestion. The supplementation of BS DFM hade evident effect over protein transport and that the use of EO in the diet enhanced the activities of carbohydrate and protein digestion, reflecting improvement in digestive and transport physiology of birds. Changes performed by BS DFM and EO did not favor performance.
Assuntos
Proteínas Aviárias/genética , Bacillus subtilis/química , Galinhas/fisiologia , Digestão/efeitos dos fármacos , Óleos Voláteis/metabolismo , Probióticos/farmacologia , Fatores Etários , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Proteínas Aviárias/metabolismo , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Expressão Gênica , Intestino Delgado/efeitos dos fármacos , Masculino , Óleos Voláteis/administração & dosagem , Probióticos/administração & dosagem , Distribuição AleatóriaRESUMO
1. An experiment was conducted to study the effect of two different diets on zootechnical performance and the major bacterial groups in association with the host mucosa and dispersed in the lumen contents of the small intestine of broiler chickens. 2. The two experimental diets were maize or sorghum-based. In addition to the total bacteria, bacterial groups belonging to the Enterobacteriaceae (Enterococcus and Lactobacillus) were quantified by real-time PCR. 3. There were no differences in body weight gain and feed intake, but feed conversion ratio increased for sorghum-fed broilers at 21 and 42 d of age. 4. The Enterococcus group decreased in all gut segments from 7 to 42 d, while the Lactobacillus group increased in both ecosystems. In the ileal mucosa, the enterobacterial counts decreased from 7 to 42 d in the maize-based diet, but remained stable in the sorghum-based diet. 5. The results shed light on the spatial and temporal distribution of bacterial groups that play important physiological roles in the small intestine of chickens. Specifically, the increased Enterobacteria population in the ileum is consistent with the relatively poor feed conversion in sorghum-fed broilers.
Assuntos
Ração Animal , Galinhas/microbiologia , Intestinos/microbiologia , Microbiota , Sorghum , Zea mays , Animais , Galinhas/fisiologia , Dieta/veterinária , Masculino , Microbiota/genética , Reação em Cadeia da Polimerase em Tempo Real/veterináriaRESUMO
Experimental studies have shown that hatching rate depends, among other factors, on the main physical characteristics of the eggs. The physical parameters used in our work were egg weight, eggshell thickness, egg sphericity, and yolk per albumen ratio. The relationships of these parameters in the incubation process were modeled by Fuzzy logic. The rules of the Fuzzy modeling were based on the analysis of the physical characteristics of the hatching eggs and the respective hatching rate using a commercial hatchery by applying a trapezoidal membership function into the modeling process. The implementations were performed in software. Aiming to compare the Fuzzy with a statistical modeling, the same data obtained in the commercial hatchery were analyzed using multiple linear regression. The estimated parameters of multiple linear regressions were based on a backward selection procedure. The results showed that the determination coefficient and the mean square error were higher using the Fuzzy method when compared with the statistical modeling. Furthermore, the predicted hatchability rates by Fuzzy Logic agreed with hatching rates obtained in the commercial hatchery.
Assuntos
Criação de Animais Domésticos/métodos , Embrião de Galinha/crescimento & desenvolvimento , Galinhas/fisiologia , Lógica Fuzzy , Óvulo/fisiologia , Envelhecimento , Animais , Embrião de Galinha/fisiologia , Modelos Logísticos , Modelos BiológicosRESUMO
Two experiments were carried out to study the effect of breeder age on incubation parameters (hatchability, eggshell thickness, egg surface temperature and chick weight). In Exp. 1, fertile eggs (30- and 60-wk-old breeders) were incubated at three different temperatures (36.8, 37.8 and 38.8 ºC). Eggshell surface temperature was measured by attaching a thermocouple to the shell and data were collected in a datalogger every ten minutes. This study was conducted according to a 3 x 2 factorial design (three temperatures and two breeder ages). Data revealed that eggshell surface temperature changed according to incubation temperature, with the main increase occurring between 10 and 13 days of incubation, and that the maximum increase in eggshell surface temperature was not higher than +0.6 ºC, irrespective of incubator temperature. The incubator temperature affected total incubation period and hatchability (%) at 38.8 ºC, independent of breeder age. Heavier eggs resulted in heavier chicks, irrespective of incubator temperature. In Exp 2, the eggs (30- and 60-wk-old breeders) were incubated at 37.8 ºC and eggs characteristics (weight, specific gravity, total hatchability and chicks weight) were evaluated according to a randomized experimental design. The data showed that breeder age affected eggshell thickness and chick weight (heavier eggs resulted in heavier chicks), but not specific gravity, eggshell surface temperature or hatchability. The findings of this study revealed that hatchability can be influenced by incubation temperature, but not by the breeder age. Breeder age can affect eggshell thickness, egg weight and eggshell surface temperature, but not specific gravity.(AU)