Evaluation of the heat‐killed and dried cell preparation of Enterococcus faecalis against villous atrophy in early‐weaned mice and pigs

Early weaning induces villous atrophy in the small intestine (SI) of piglets. Oral administration of live lactic acid bacteria (LAB) can improve villous shortening. In this study, we evaluated the oral administration of a heat‐killed and dried cell preparation of Enterococcus faecalis (a LAB) strain EC‐12 against villous atrophy in early‐weaned mice (Experiment 1) and pigs (Experiments 2 and 3). Twelve 16‐days‐old mice were divided into two groups in Experiment 1: gavage of EC‐12 (10 mg/kg body weight (BW)/day), or control. On day 21, SI was collected. Eighteen 21‐day‐old pigs were divided into two groups in Experiment 2: gavage of EC‐12 (10 mg/kg BW/day), or control. After 10 days, the villous height of jejunum was measured. Six 21‐day‐old pigs were divided into two groups in Experiment 3: the basal diet supplemented with EC‐12 at 0.05%‐fed group, or the basal diet‐fed group. After 10 days, the villous height of jejunum was measured. The villous heights in SI were significantly higher by EC‐12 administration in all experiments. EC‐12 successfully improved the villous atrophy in the early‐weaned mice and pigs when EC‐12 was administered orally.     

An epidemiological survey on pigs showing symptoms of infectious enteric diseases and dyspepsia in Japan

Diarrhea in pigs has the potential to have a serious economic impact on the swine industry. Previously, we suggested that the likely cause of the presence of non-infectious diarrhea in pigs characterized by lactate accumulation was dyspepsia. In this experiment, the prevalence of enteropathogens and hyper-lactate accumulation in feces of piglets in 4 distinct growth stages was examined. The feces were collected when veterinarian experts recognized abnormalities in sporadic outbreaks. Prevalence of enteropathogens in diarrheal feces was 100% in fattening pigs (FP), 75% in weaning pigs (WP), 50% in suckling pigs (SP), and 42% in growing pigs (GP). Prevalence of enteropathogens in loose feces was 53% in WP, 50% in SP, 40% in FP, and 28% in GP. Prevalence of hyper-lactate accumulation in diarrheal feces was 33% in GP, 33% in SP, 25% in WP, and 25% in FP. Prevalence of hyper-lactate accumulation in loose feces was 40% in GP, 0% in SP, 7% in WP, and 5% in FP. Accordingly, non-infectious dyspepsia is frequent in growing pigs. In this period, pigs are potentially exposed to needless antimicrobial therapeutic treatments in sporadic cases.     

Ontogenetic development during changeover from an endogenous to exogenous nutritional source in Laotian cyprinid <Emphasis Type="Italic">Cirrhinus microlepis</Emphasis> larvae

The nutritional transition process from endogenous to exogenous feeding in larvae of the Laotian indigenous cyprinid Cirrhinus microlepis was investigated approximately 200 h after hatching. Although 17 characters were observed, emphasis was given to those associated with the onset of feeding and subsequent development of feeding ability. Growth of larvae was divided into two phases, rapid growth (to 71.5 h) and slower growth (from 71.5 h). The yolk absorption pattern was divided into four phases, the rapid yolk consumption (to 21 h), slow yolk consumption (to 71.5 h), complete yolk consumption (to 118.5 h) and post-yolksac phases. Onset of feeding was observed at the end of the slow yolk consumption phase (71.5 h after hatching), and notochord flexion, appearance of caudal fin supports/rays and gut coiling were observed at the same time. Comparisons of developmental characters relevant to the onset of feeding between C. microlepis and sympatric species, including Trichogaster pectoralis, Anabas testudineus and Pangasianodon hypophthalmus, revealed that morphological features related to the nutritional changeover were most likely linked to the habitat environment and survival strategy of early larvae.     

When do rice terraces become rice terraces?

Paddy and Water Environment - Rice terraces located on sloped hills in mountainous areas are sometimes abandoned because of lack of labor and difficulties associated with cultivation. Recently,...     

A National Surveillance of Shiga Toxin‐Producing Escherichia coli in Food‐Producing Animals in Japan

To assess the public health risk, the prevalence and anti‐microbial resistance of Shiga toxin‐producing Escherichia coli (STEC) among food‐producing animals were studied throughout Japan. Faecal samples were collected from healthy animals of 272 cattle, 179 pigs, and 158 broilers on 596 farms in all 47 Japanese prefectures. STEC were isolated from 62 (23%) cattle and 32 (14%) pig samples but from no chicken samples. Of the bovine isolates, 19 belonged to serotypes frequently implicated in human disease (O157:H7/non‐motile (NM)/H not typeable, O26:NM/H11/H21/H not typeable, O113:H21, and O145:NM). The eae genes were observed in 37% of bovine isolates; among them one O145:NM and all four O157 isolates possessed eae‐γ1, and one O145:NM, one O103:H11, and all five O26 isolates possessed eae‐β1 gene. Among the swine isolates, stx2e were dominant, and serotypes frequently implicated in human diseases or eae‐positive isolates were not observed. Bovine isolates showed less anti‐microbial resistance, but six isolates of 26:NM/H11 and O145:NM were multi‐resistant and may need careful monitoring. Swine isolates showed various resistance patterns; chloramphenicol resistance patterns were more common than in bovine isolates. This first national study of STEC in the Japanese veterinary field should aid our understanding of Japan's STEC status.     

Stimulation of butyrate production through the metabolic interaction among lactic acid bacteria, Lactobacillus acidophilus, and lactic acid-utilizing bacteria, Megasphaera elsdenii, in porcine cecal digesta

In this study, we examined the potential of Megasphaera elsdenii as a probiotic agent in combination with sodium gluconate. We also examined the combination of M. elsdenii with probiotic lactic acid bacteria (LAB), Lactobacillus acidophilus, to enhance butyrate production in the large intestine using a pig cecal in vitro model under the presence of sodium gluconate. Compared to the uninoculated control culture (with only diluted cecal digesta), the addition of M. elsdenii and LAB to the culture stimulated significantly the production of n‐butyrate (60% increase) and n‐valerate (50% increase) after 24 h incubation. n‐Butyrate is regarded as the most important short‐chain fatty acid in the large intestine because it stimulates the proliferation of epithelial cells, mucus release and water and mineral absorption. Therefore, lactate‐utilizing butyrate producers such as M. elsdenii play a significant role in supporting the health‐beneficial effects of lactogenic prebiotics and probiotics LAB. The potential of M. elsdenii as a probiotic was also suggested.     

Effects of low protein intake on the development of the remaining kidney in subtotally nephrectomized immature rats: apoptosis and epidermal growth factor

Effects of low protein intake on the development of the remaining kidney in subtotally (5/6) nephrectomized immature rats were examined. Three week-old weaning rats were kept on a diet containing either 12% (Lp rats) or 18% (Np rats) protein for 4 or 8 weeks after subtotal nephrectomy. Blood urea nitrogen (BUN) concentration was determined at 2, 4, 6, and 8 weeks after 5/6 nephrectomy. At 4 or 8 weeks after the operation, glomerular sclerosis and tubulointerstitial damage were assessed by a standard semiquantitative analysis and were expressed as the glomerular sclerosis index (GSI) and interstitial fibrosis score (IFS), respectively. The localization of DNA fragmented cells in the kidney was examined by the terminal deoxynucleotidyl transferase (TdT) -mediated d-UTP-biotin nick end labeling (TUNEL) method and the localization of the epidermal growth factor (EGF) by immunohistochemical methods. BUN concentration was significantly lower in the Lp rats compared with that in the Np rats. Both 4 and 8 weeks after subtotal nephrectomy, GSI and incidence of TUNEL positive cells in the distal tubules were significantly lower in the Lp rats than in the Np rats. Four weeks after the operation, IFS was significantly lower in the Lp rats than in the Np rats. Four and 8 weeks after the operation, EGF positive cells in the distal tubules were more observed in the Lp rats than in the Np rats. These findings reveal that protein restriction is effective in preventing renal tubular scarring in immature rats and that EGF is involved in the process of this prevention.     

Shiga toxin 2eB-transgenic lettuce vaccine: N-glycosylation is important for protecting against porcine edema disease

Porcine edema disease (ED) is a life-threatening toxemia caused by enteric infection with Shiga toxin 2e (Stx2e)-producing Escherichia coli (STEC) in weaned piglets. We previously reported that the stx2eB-transgenic lettuce 2BH strain shows potential for use as an oral vaccine candidate against ED. However, the 2BH strain expressed a hemagglutinin (HA)-tag together with Stx2eB and contained non-canonical N-glycosylation. Therefore, we developed two Stx2eB-lettuce strains, the 3 (G+) strain in which the HA-tag was removed from 2BH, and the 3 (G-) lettuce strain, in which the 73rd Asn was replaced with Ser to prevent non-canonical N-glycosylation of Stx2eB from the 3 (G+) strain. We examined the protective effect of these newly developed two strains compared with the previous 2BH strain against ED using a colostrum-deprived piglet STEC infection model. We found that the N-glycosylated 2BH and 3 (G+) strains relieved the pathogenic symptoms of ED in STEC-challenged piglets, whereas the non-glycosylated 3 (G-) strain did not. N-Glycosylation of the Stx2eB product in lettuce may be involved in the immune response in piglets.     

An experimental infection in pigs using a foot-and-mouth disease virus isolated from the 2010 epidemic in Japan

In this study, we carried out an experimental infection in pigs using a foot-and-mouth disease virus isolated from the 2010 epidemic in Japan to analyze the clinical manifestation, antibody response and virus shedding patterns in pigs. We found that the virus was virulent in pigs, producing a synchronous disease in the inoculated pigs and efficient spread to direct contact pigs. These results are useful for epidemiologically investigating the 2010 epidemic in Japan and improving the measures for controlling possible future FMD outbreaks in Japan or elsewhere.