Effects of early feeding and exogenous putrescine on growth and small intestinal development in posthatch ducks

Lentils pasta by-product in a complete extruded diet for dogs and its effect on extrusion, digestibility, and carbohydrate metabolism

Introduction

Recently, increasing effort has been directed toward environmental sustainability in pet food. The aim of this study was to evaluate the extrusion parameters, nutrient digestibility, fecal characteristics, palatability and insulinemic and glycaemic curves of a complete diet for dogs in which the main carbohydrate source was a red lentil pasta by-product (LP).

Methods

Five experimental diets were formulated: a basal diet (CO) based on rice and a poultry by-product meal; three experimental diets where LP substituted rice at 33, 66, or 100% (LP33, LP66, and LP100, respectively); and a diet formulated on 70% of the basal diet (CO) plus 30% LP (LPS) to evaluate the digestibility of LP ingredient.

Results and discussion

The extruder pressure, hardness and bulk density of the kibble increased in a linear manner with increasing LP percentage (P < 0.05), without affecting starch gelatinization. According to polynomial contrast analysis, rice replacement with LP at 33 and 66% caused no reduction in apparent total tract digestibility coefficient (ATTDC), with similar or higher values compared with the CO diet. Nitrogen balance did not change (P > 0.05), but we observed a linear increase in feces production and moisture content as the LP inclusion rate rose and a linear decrease in feces pH (P < 0.05). Nevertheless, the fecal score was unaffected. Fecal acetate, propionate, total short-chain fatty acids (SCFA), branched-chain fatty acids, and lactate all increased linearly as the LP inclusion rate increased (P < 0.05), without altering ammonia concentration in feces. Feces concentrations of cadaverine, tyramine, histamine, and spermidine also increased in a linear manner with increasing LP inclusion (P < 0.05). The fermentation of LP dietary fiber by the gut microbiota increased the concentration of desirable fermentation by-products, including SCFA and spermidine. The post-prandial glucose and insulin responses were lower in the dogs fed the LP100 diet compared with CO, suggesting the possible use of this ingredient in diets designed to generate a low glycaemic response. Finally, the palatability study results showed a preference for the LP100 ration in both the "first choice" and the "consumption rate" evaluation (P < 0.05). This trial reveals how a by-product discarded from the human-grade food chain retains both its nutritional and organoleptic properties.

Deciphering survival strategies: Oxidative stress and microbial interplay in Eisenia fetida under tetracycline contamination

Soil contamination resulting from residual antibiotics presents a pressing need to understand the survival mechanisms of soil organisms in polluted environments. This study focused on Eisenia fetida, and tetracycline stress experiments were conducted in a controlled environment using sterile artificial soil. The stress concentration ranged from 0 to 600 mg/kg, and stress cycles lasted either 10 or 30 days. The objective of this study was to assess the effects of oxidative stress and the changes in microbial communities both within and outside the earthworms. A comprehensive mathematical model was developed to elucidate the responses of organisms following exposure to stress utilizing factor analysis, grey relational analysis, and hierarchical entropy weight analysis. Under tetracycline stress, the initial stage (1-3 days) exhibited a coordinated regulation of oxidative stress and microbial communities in the soil with the assistance of CAT and GPX enzymes. The subsequent stage (4-5 days) further emphasized the influence of soil microbial communities. A notable "feedback regulation" of soil microbial communities on oxidative stress was observed during the third stage (6-8 days). Earthworms maintained a metabolic balance in the fourth stage (9-10 days). In the long term, the stress-induced a self-detoxification mechanism within soil microbial communities, which collaborated with GPX to respond to oxidative stress.

Effects of early posthatch feeding on growth, organ development, and blood biochemical profile in broiler chickens

The effects of early feeding time on growth performance, organ weight, blood biochemical, and leukocyte profile were investigated in posthatch broiler chickens to 35 d of age. From 7 to 21 d, early feeding (3 h after hatching) had a significant (p < 0.01) effect on body weight gain, and at 14 d, chicks fed 3 and 12 h after hatching were significantly heavier (p < 0.01) than those fed later. At 7 d, feed intake (FI) was significantly higher (p < 0.01) among chicks fed 3 and 12 h after hatching. At 21 d, chicks fed 3 h after hatching showed significantly higher FI (p < 0.01) than those fed later. At 3 d, gizzard weight was significantly heavier (p < 0.05) in chicks fed 24, 36, and 48 h after hatching than in those fed earlier, and small intestinal weight was also significantly higher (p < 0.05). At 35 d of age, alanine aminotransferase was higher (p < 0.01) in chicks fed 36 and 48 h after hatching, and the eosinophil level was significantly higher (p < 0.01) in chicks fed 3, 24, 36, and 48 h after hatching.

In ovo administration of rhIGF-1 to duck eggs affects the expression of myogenic transcription factors and muscle mass during late embryo development

In ovo administration of IGF-1 to poultry eggs has effective roles on post hatching muscle development. However, the secondary muscle development stages at the late embryo development stage are important for muscle fiber formation and differentiation. To investigate the roles of in ovo administration of IGF-1 on duck secondary muscle development, we injected rhIGF-1 into duck eggs in hatching at day 12. After administration on days 18, 21, 24, and 27 in hatching (E18d, E21d, E24d, and E27d, respectively), muscle samples were isolated, and the muscle tissue weight, muscle fiber parameters, and myoblast proliferation rate in leg and breast muscle were analyzed. Additionally, the expression levels of the transcription factors MyoG and MRF4 were detected using qPCR. Results show that embryo body weight and muscle fiber parameters, including muscle fiber diameter (MFD) and the number of myofibers per unit area, are upregulated in IGF-1-treated groups. Moreover, the transcription factors MyoG and MRF4 are expressed at higher levels in the experimental groups compared with the control groups. These results suggest that in ovo administration of IGF-1 to poultry eggs can mediate the expression of MyoG and MRF4, induce myoblast proliferation, and finally influence muscle development during the secondary muscle development stages.