Effect of bilateral cecal ligation on use of dietary energy in growing chickens

In order to determine the role of the cecum on energy use in growing chickens, metabolizability of the dietary energy and energy expenditure were examined in the week following bilateral ligation and washing out of the cecum. Apparent metabolizable energy (AME) values were 14.30 and 13.69 kJ/g air‐dry matter for sham‐operated and cecally ligated chickens, respectively. These values were found to be significantly different (P < 0.05). Although AME intake and fasting heat production were decreased by cecal ligation, the distribution of AME (measured as fasting and feeding heat production, as well as heat increment and energy retention, as a proportion of AME intake) was not affected. These results suggest that the cecum helps chickens extract AME from corn‐soybean type diets with little, if any, effect on AME use, based on the present study of growing chickens in the week following cecal ligation.     

Pharmacokinetics and effects on clinical and physiological parameters following a single bolus dose of propofol in common marmosets (Callithrix jacchus)

The objectives of this study were (a) to establish a population pharmacokinetic model and (b) to investigate the clinical and physiological effects of a single bolus dose of propofol in common marmosets. In Study 1, pharmacokinetic analysis was performed in six marmosets under sevoflurane anaesthesia. 8 mg/kg of propofol was administrated at a rate of 4 mg kg^?1 min^?1. Blood samples were collected 2, 5, 15, 30, 60, 90, 120 or 180 min after starting propofol administration. Plasma concentration was measured, and population pharmacokinetic modelling was performed. A two‐compartment model was selected as the final model. The population pharmacokinetic parameters were as follows: V₁ = 1.14 L, V₂ = 77.6 L, CL₁ = 0.00182 L/min, CL₂ = 0.0461 L/min. In Study 2, clinical and physiological parameters were assessed and recorded every 2 min after 12 mg/kg of propofol was administrated at a rate of 4 mg kg^?1 min^?1. Immobilization was sustained for 5 min following propofol administration without apparent bradycardia. While combination of propofol and sevoflurane caused apnoea in Study 1, apnoea was not observed following single administration of propofol in Study 2. These data provide bases for further investigation on intravenous anaesthesia using propofol in common marmosets.     

Evaluation of shrimp polyculture system in Thailand based on stable carbon and nitrogen isotope ratios

ABSTRACT: To quantify the contribution by cocultured animals to waste assimilation in an intensive shrimp farm in Thailand, the food web structures of the macrobenthos in a reservoir pond, a shrimp culture pond and water treatment ponds were examined using the stable C and N isotope ratio technique. Seawater for aquaculture was drawn from a creek, and stored in a reservoir pond, used for farming the banana prawn Fenneropenaeus merguiensis in culture ponds, and then recycled through treatment ponds where the green mussel Perna viridis was cultured to remove organic wastes discharged from the farming. The clam worm Nereididae sp. and the mud creeper Cerithideopsilla cingulata in the culture pond had δ ¹³C values of −21.0‰ and −18.4‰, respectively, suggesting that shrimp feed (mean δ ¹³C = −20.7‰) was the main food source for these species. The δ ¹³C analysis also suggested that sediments (−23.7‰) in the reservoir pond and particulate organic matter (POM) (−24.0‰) and/or sediments (−25.0‰) in the treatment pond supplied carbon for most macrobenthic animals. However, green mussels in the treatment pond had a mean δ ¹³C value of −20.5‰, suggesting that shrimp feed was the main food source for this species.     

Beneficial effects on meat quality of yellowtail Seriola quinqueradiata induced by diets containing red pepper

The meat quality of farmed yellowtail Seriola quinqueradiata fed on extruded pellets (EP) containing 0.5% (v/v) red pepper (experimental group) was compared with yellowtail of the same age fed on EP (control group). In 1-year-old yellowtail, the crude lipid content of the dorsal muscle of the experimental group tended to be lower than that of the control group. In contrast, there was no difference in the lipid content of the dorsal muscle between the control group and the experimental group in 2-year-old yellowtail. The muscle texture of the experimental group was significantly firmer than that of the control group, with the effect of red pepper unrelated to fish age and lipid content. Color change of red muscle of the experimental group was significantly lower than that of the control group, and the content of thiobarbituric acid-reactive substances in the red muscle was significantly lower in the experimental group than in the control group. These results are the first to demonstrate that the inclusion of red pepper in the diet is able to reduce the loss of muscle texture firmness and to slow down color change in red muscle of yellowtail.     

The renal structure in an Asian elephant (Elephas maximus)

The renal structure of a female Asian elephant (Elephas maximus) was observed in both macroscopic and light microscopic levels. The left kidney was elongated-ellipse in shape, whereas the right appeared round. The left kidney was 31 cm in cranio-caudal length, 21 cm in medio-lateral length, and 2950 g in weight. The right kidney was 34 cm in cranio-caudal length, 22 cm in medio-lateral length, and 3250 g in weight. The external appearance showed the six separated renal lobes in both sides of the kidney. The four pairs of the lobes were fused in the deepest region in both sides of kidney, so we considered it as an incompletely lobated kidney in this species. We observed the proximal and distal urinary tubules in histological sections. Many renal corpuscles consisted of the glomerulus and Bowman's capsule. Many mesangial cells and some podocytes were confirmed in each glomerulus; however, Bowman's capsules were larger than those in other mammalian species.     

Effect of regular walking exercise on glucose tolerance and insulin response to i.v. glucose infusion in growing beef steers

The purpose of the present paper was to investigate the effect of regular walking exercise on glucose tolerance and insulin response to i.v. glucose infusion in growing beef steers. Four crossbred beef steers walked on a treadmill during a 6 week exercise period (1.2 km/h, 1 h/day and 5 days/week). The changes in plasma glucose and insulin levels following glucose infusion were analyzed immediately prior to (bodyweight: 260.4 ± 24.2 kg) and after (295.7 ± 30.1 kg) the exercise period. The basal levels of plasma glucose (86.4 vs. 82.0 mg/dL, P = 0.040) and insulin (24.5 vs. 14.3 μU/mL, P = 0.016) were significantly lower after the exercise period. Further, the increase in the levels of plasma glucose (420.4 vs. 280.8 mg/dL, P < 0.001) and insulin (94.5 vs. 73.1 μU/mL, P = 0.028) following the glucose infusion decreased after the exercise period. The area under the curve of plasma glucose (108.8 vs. 62.9 mg/dL per min, P < 0.001) and insulin (53.6 vs. 29.7 μU/mL per min, P = 0.018) indicated more rapid clearance of exogenous glucose and less insulin secretion for glucose clearance after the exercise period. These results suggest that regular exercise improves glucose tolerance, with lower insulin response to glucose infusion in growing steers, as observed in rodents and humans.     

Preliminary experiments on mechanical stretch-induced activation of skeletal muscle satellite cells in vivo

We have shown in vitro that mechanical stretch triggers activation of quiescent satellite cells of skeletal muscle to enter the cell cycle through an intracellular cascade of events including nitric oxide (NO) synthesis that results in the release of hepatocyte growth factor (HGF) from its extracellular association and its subsequent presentation to signaling receptors. In order to explore the activation mechanism in vivo, stretch experiments were conducted in the living animal using our suspension model developed. This system used the weight of the hind portion of rats to stretch the inside muscles of the left hind limb suspended for a period of 0.5–2.0 h. At the end of the stretch period, the rats received an intraperitoneal injection of bromodeoxyuridine followed by immunocytochemistry for its incorporation as an index of satellite cell activation in vivo. Depending on the period of stretch, bromodeoxyuridine labeling was increased significantly over the contralateral unstretched leg or control muscle from untreated rats. A stretched muscle extract prepared from the 2 h stretched tissue by incubating it in PBS, showed the active form of HGF as revealed by immunoblotting and it could stimulate the activation of unstretched satellite cells. Also, administering NO synthase inhibitor L‐NAME prior to muscle stretch abolished the stretch activation of satellite cells. Therefore, the results from these experiments demonstrate that stretching muscle triggers NO synthesis and HGF release, which could activate satellite cells in vivo.