Fast neutron irradiation deteriorates hippocampus-related memory ability in adult mice

Object recognition memory and contextual fear conditioning task performance in adult C57BL/6 mice exposed to cranial fast neutron irradiation (0.8 Gy) were examined to evaluate hippocampus-related behavioral dysfunction following acute exposure to relatively low doses of fast neutrons. In addition, hippocampal neurogenesis changes in adult murine brain after cranial irradiation were analyzed using the neurogenesis immunohistochemical markers Ki-67 and doublecortin (DCX). In the object recognition memory test and contextual fear conditioning, mice trained 1 and 7 days after irradiation displayed significant memory deficits compared to the sham-irradiated controls. The number of Ki-67- and DCX-positive cells decreased significantly 24 h post-irradiation. These results indicate that acute exposure of the adult mouse brain to a relatively low dose of fast neutrons interrupts hippocampal functions, including learning and memory, possibly by inhibiting neurogenesis.     

Effects of fermented mushroom (Flammulina velutipes) by‐product diets on growth performance and carcass traits in growing‐fattening Berkshire pigs

This study was conducted to investigate effects of fermented mushroom (Flammulina velutipes) by‐product diets on the growth performance and carcass traits in growing‐fattening Berkshire pigs. The fermented diets mainly contained 40.0% mushroom by‐product, 20.0% formula feed, 26.0% rice bran and supplemental 0.1% probiotics. The mixed ingredients were fermented for 5 days at room temperature. Berkshire pigs (n = 225) were divided into five groups and three replications. The basal diets (C) were substituted by 10% (T1), 30% (T2), 50% (T3) and 70% (T4) fermented mushroom by‐product diets. Crude protein concentration and total calorie in fermented diets were significantly increased (P < 0.05) at the end of fermentation days compared with initial fermentation day. Body weight gain, feed efficiency and carcass weight were significantly lower (P < 0.05) in the T2, T3 and T4 groups than in the control group. Carcass grade was significantly better (P < 0.05) in the pigs fed fermented diets than in the pigs fed control diet and the ratio of high grade (1 plus 2 grades) was higher in the fermented diet groups compared with the control group. Therefore, although a diet of fermented mushroom by‐product decreased growth performance and feed efficiency, it improved the carcass grade in Berkshire pigs.     

Spatial distribution and spread of sheep biting lice, Bovicola ovis, from point infestations

The spatial distribution of chewing lice (Bovicola ovis) on their hosts was examined in Polypay and Columbia ewes initially artificially infested on the midside or the neck. Densities of lice were determined at 69 body sites in eight body regions at approximately monthly intervals for 2 years. In the second year, half of the ewes were mated and lice were counted at 26 body sites on the resulting lambs. Polypay ewes had higher densities of lice than Columbias at most inspections but there was little effect of infestation point or mating on either numbers or the distribution of lice. During periods of high louse numbers densities were generally greatest on the sides or the back. Densities on the head were also high at times and peaked later than overall louse densities. Shearing markedly reduced density but increased the proportion of lice found on the neck, belly and lowleg sites. The distribution of lice on the lambs was similar to that on the ewes except that fewer lice were found on the head. Comparisons of lice per part with the numbers of lice extracted from clipped patches indicated that a sheep with wool bearing area of 1 m2 and a mean count of one louse per 10 cm fleece parting carried approximately 2000 lice. At most times of the year inspections for sheep lice should be concentrated on the sides and back, but in recently shorn sheep greater attention should be paid to the lower neck and ventral regions. Implications of the observed distributions of lice for the efficacy of chemical treatments are discussed.     

Experimental evaluation of urinary bladder marsupialization in male goats

OBJECTIVE: To evaluate the outcome of urinary bladder marsupialization in male goats. STUDY DESIGN: Prospective, experimental study. ANIMALS: Six healthy mixed-breed male goats. METHODS: After experimentally induced urethral obstruction, 6 male goats had urinary bladder marsupialization. Renal ultrasonography, complete blood count, and serum biochemical analysis were evaluated preoperatively (day 0), at 7 postoperative days, and then at 30-day intervals until 180 days. Stomal diameter was recorded immediately postoperatively and at each postoperative interval. Necropsy examination was performed on day 180 or when stomal stricture or death occurred. RESULTS: Stomal stricture occurred in 1 goat at 120 days. Another goat was found dead at 150 days; severe, suppurative cystitis was identified on necropsy. All goats had mild urine scald dermatitis. Serum biochemical values remained within normal limits, but significant decreases in white blood cell count, serum creatinine concentration, and stomal diameter occurred. At necropsy, all bladders were tubular in shape. Histological evidence of chronic suppurative cystitis and chronic, mild lymphoplasmacytic pyelitis occurred in all goats. Bacterial culture of renal tissue yielded growth in 3 goats, and bladder mucosal swabs yielded bacterial growth in all goats. CONCLUSIONS: Although clinical signs of ascending urinary tract infection were not observed in goats with patent stomata, urinary bladder marsupialization may result in ascending urinary tract inflammation or infection. CLINICAL RELEVANCE: Based on our results, urinary bladder marsupialization should be recommended with caution as the primary method for management of urinary tract obstruction in clinical cases.     

Influence of slaughter weight and sex on yield and quality grades of Hanwoo (Korean native cattle) carcasses

To assess the effects of slaughter weight and sex on APGS (Animal Products Grading Service) quality and APGS yield grade of Korean Hanwoo (n = 20,881) cattle, data were collected from cow, bull, and steer carcasses during a 1-yr period. Factors used to determine quality grade (marbling, meat color, fat color, texture, and overall maturity score) and yield grade (cold carcass weight, adjusted fat thickness, and longissimus muscle area) by the Korean grading system were recorded. Both yield and quality grades were improved (P < 0.01) with heavier slaughter weight, but there was no difference in yield grade for Hanwoo cattle classes heavier than 551 kg (P > 0.01). Longissimus muscle area, adjusted fat thickness, and marbling score increased (P < 0.01) with carcass weight. Bull carcasses showed higher yield but lower quality than those of cows or steers (P < 0.01). The quality grade of steer carcasses was higher (P < 0.01) than that of cow carcasses due to higher marbling scores, lower maturity scores, and heavier carcass weights. Hanwoo carcasses with larger longissimus muscle areas in relation to their carcass weight had lower APGS quality grades. The APGS quality grades were different between yield grade A and B carcasses (P < 0.01), but quality grade was not improved by increased fat thickness beyond the point of yield grade B. Adjusted fat thickness and marbling score showed significant (P < 0.01) differences among all yield grade classes, and this resulted in increased quality grade as yield grade decreased. Adjusted fat thickness showed the strongest correlation (r = -0.63) with yield grade, whereas marbling score had the strongest correlation (r = 0.81) with quality grade. Results showed a negative effect of castration on yield but a positive effect on quality. Also, data showed that Hanwoo carcasses with heavier weights had higher quality grades than those of lighter weight.     

Localization and activities of lysosomal enzymes in jejunal and ileal epithelial cells of the young pig

The localization and the specific activities of lysosomal enzymes in jejunal and ileal epithelium of suckling pigs were determined. Acid phosphatase was found in pinocytotic vesicles and vacoles at both intestinal sites in pigs examined during (less than or equal to 1 day old) or shortly after (2 days old) closure. These pinocytolically active vesicles and vacuoles were determined to be phagolysosomes. In the ileum, phagolysosomes persisted well after closure, at an age (10 days) when ileal epithelium retains the capacity for pinocytotic uptake of immunoglobulin, but does not transport it to blood. Neither jejunum nor ileum contained phagolysosomes at an age (30 days) when the intestine had lost both uptake and transport capacities. The specific activities of acid phosphatase and cathepsin B-1 in jejunum were similar for all age groups. However, the activities of these enzymes in ileum of 10-day-old pigs were three and five times greater than at any other age or site. The results are consistent with phagolysosomes in the ileum of 10-day-old pigs functioning as a "barrier" which prevents transport of the macromolecules which are taken up pinocytotically by this epithelium. The results do not permit conclusions whether (or not) the phagolysosomes which appear in jejunum and ileum of pigs less than or equal to 1 day old contribute to closure, because the transcellular route for immunoglobulin absorption in pigs has not been precisely defined.     

Effect of Partial Acid Hydrolysis and Heat‐Moisture Treatment on Formation of Resistant Tuber Starch

Structural characteristics of resistant starch (RS) were investigated. Tuber starches, hydrolyzed with 1N HCl at 35°C for 8 hr followed by autoclaving‐cooling treatment, were heated at 100°C for 16 hr after adjusting the moisture content to 20 or 30%. RS content of the tuber starches ranged from 5.4 to 22.7% depending on the source and type of treatment. Gelatinization parameters of RS isolated from partially acid‐hydrolyzed starch with autoclaving‐cooling followed by heat‐moisture treatment (HMT) showed higher enthalpy (ΔH) values and lower peak temperature (T_p) compared with non‐acid‐hydrolyzed RS. R values, the difference between completion and initial temperatures, and ΔH of RS increased by HMT. The X‐ray diffraction patterns of potato and sweet potato RS isolated from partially acid‐hydrolyzed starch with autoclaving‐cooling showed distinct sharp peaks at 15, 25, 27, and 28°, which decreased by HMT.     

Comparative stomach contents and growth of the juvenile black rockfish Sebastes inermis reared in illuminated and unilluminated cages

ABSTRACT:   The principal objective of the present study was to determine the positive effects of artificial illumination on the juvenile black rockfish Sebastes inermis by comparing stomach contents and growth between juveniles exposed to light and those maintained in the absence of light. The major prey items of juvenile black rockfish in illuminated cages were: copepods (% IRI  = 62.6); amphipods (% IRI  = 36.7); and polychaetes (% IRI  = 0.3), whereas those in unilluminated cages were: copepods (% IRI  = 93.3); amphipods (% IRI  = 6.1); and polychaetes (% IRI  = 0.4). The specific growth rates of the juveniles reared in illuminated cages (0.67%) were significantly higher than those juveniles maintained in the unilluminated cages (0.27%).