Feed or feed transport as a potential route for a porcine epidemic diarrhoea outbreak in a 10,000-sow breeding herd in Mexico.

Porcine epidemic diarrhoea virus (PEDV) infects pigs of all ages causing vomiting and diarrhoea. PEDV is transmitted via the oral-faecal route, and a very low dose is enough to infect susceptible pigs, resulting in significant production losses. This short communication aims to describe the introduction of PEDV into a 10,000-sow farrow-to-wean farm located in northwest Mexico. Following the onset of clinical signs, an outbreak investigation was conducted to determine the most probable route of introduction. Based on data collected from interviews, construction of a timeline of events, and the detection of PEDV RNA in feed samples and samples collected from various surfaces of feed transport vehicles, it was concluded that the most probable route for PEDV incursion into this breeding herd was contaminated feed or a contaminated feed transport vehicle. This paper describes how feed or feed transport could serve as potential routes of PEDV infection to a farm and highlights the importance of establishing biosecurity programs to mitigate these risks.

Development of phage delivery by bioencapsulation of artemia nauplii with Edwardsiella tarda phage (ETP-1).

This study proposed that phage-enriched artemia could be a useful tool for transferring phage into the cultured fish (larvae or adult) as a feed, and introduce mode of phage administration and its safety in concern of tissue adaptation for efficient phage therapy in aquatic animals. First, whether Edwardsiella tarda phage (ETP-1) could attach or ingest by the artemia and optimum time period for the ETP-1 enrichment with artemia were investigated. ETP-1 dispersion, abundance and persistency, and zebrafish immune transcriptional responses and histopathology were evaluated after feeding the fish with ETP-1-enriched artemia. Hatched artemia nauplii (36 h) were enriched with 1.90 × 1011 PFUmL-1 of ETP-1, and maintained at 25 °C. The highest enrichment level was obtained after 4 h (3.00 × 109 PFUmL-1), and artemia were alive and active similar to control for 8 h. ETP-1 disseminated dose dependently to all the tissues rapidly (12 h). However, when feeding discontinued, it drastically decreased at day 3 with high abundance and persistency in the spleen (1.02 × 103) followed by the kidney (4.00 × 101) and the gut (1 × 101 PFUmL-1) for highest ETP-1-enriched artemia dose. In contrast, during continuous delivery of ETP-1-enriched artemia, ETP-1 detected in all the tissues (at day 10: gut; 1.90 × 107, kidney; 3.33 × 106, spleen; 5.52 × 105, liver; 6.20 × 104 PFUmL-1mg-1 tissues). Though the phage abundance varied, results indicated that oral fed ETP-1-enriched artemia disperse to the neighboring organs, even the absence of host as phage carrier. Non-significant differences of immune transcriptional and histopathology analysis between ETP-1-enriched artemia fed and controls suggest that no adverse apparent immune stimulation in host occurred, and use of ETP-1 at 1011 PFUmL-1 was safe. With further supportive studies, live artemia-mediated phage delivery method could be used as a promising tool during phage therapy against pathogenic bacteria to control aquatic diseases.

Experimental infection of Salmonella Enteritidis in quails submitted to forced molting by feed fasting

This study aimed at evaluating bacterial shedding, as detected in swabs, feces, and eggs of quails submitted to forced molting by feed fasting and experimentally infected with a Salmonella Enteritidis (SE) strain. In the experiment, 84 40-week-old Italian female quails were distributed in the following groups: FI (quails induced to molt by fasting and inoculated with Salmonella Enteritidis - SE); CI (quails fed with a laying diet and inoculated with SE); FNI (quails induced to molt by fasting and not inoculated with SE); and CNI (quails fed with a laying feed and not inoculated with SE). Feces, cloacal swabs, and eggs were collected on day 1, 3, 7 and 14 post-inoculation (dpi) and submitted to bacteriological analyses. All samples obtained from cloacal swabs were negative for SE. None of the quails of the non-inoculated groups (FNI and CNI) were positive for SE in the fecal samples. Among the inoculated quails, the FI group presented significantly higher (p 0.05) SE shedding in the feces on 1 dpi than the CI group. On 4 dpi, no significant difference was observed (p 0.05) in SE shedding between the inoculated quail groups. On 7 dpi, only the FI group shed SE in the feces, whereas on 14 dpi, none of the groups shed SE. According to the results, we concluded that quails submitted to molting by fasting have higher possibility of shedding SE in the feces.

Experimental infection of Salmonella Enteritidis in quails submitted to forced molting by feed fasting

This study aimed at evaluating bacterial shedding, as detected in swabs, feces, and eggs of quails submitted to forced molting by feed fasting and experimentally infected with a Salmonella Enteritidis (SE) strain. In the experiment, 84 40-week-old Italian female quails were distributed in the following groups: FI (quails induced to molt by fasting and inoculated with Salmonella Enteritidis - SE); CI (quails fed with a laying diet and inoculated with SE); FNI (quails induced to molt by fasting and not inoculated with SE); and CNI (quails fed with a laying feed and not inoculated with SE). Feces, cloacal swabs, and eggs were collected on day 1, 3, 7 and 14 post-inoculation (dpi) and submitted to bacteriological analyses. All samples obtained from cloacal swabs were negative for SE. None of the quails of the non-inoculated groups (FNI and CNI) were positive for SE in the fecal samples. Among the inoculated quails, the FI group presented significantly higher (p 0.05) SE shedding in the feces on 1 dpi than the CI group. On 4 dpi, no significant difference was observed (p 0.05) in SE shedding between the inoculated quail groups. On 7 dpi, only the FI group shed SE in the feces, whereas on 14 dpi, none of the groups shed SE. According to the results, we concluded that quails submitted to molting by fasting have higher possibility of shedding SE in the feces.(AU)

Comparative effects of dietary administered transgenic and conventional papaya on selected intestinal parameters in rat models.

Transformation of agricultural crops with novel genes has significantly advanced disease-resistance breeding, including virus resistance through the expression of virus sequences. In this study, the effects of long-term, repeated exposure to transgenic papayas carrying the coat protein gene of Papaya ringspot virus and conventional non-transgenic papaya on the histology and selected biochemical parameters of the intestinal tract were compared. For 3 months, male and female Wistar rats received diets containing transgenic or non-transgenic papaya at twice the equivalent of the average daily consumption of fresh papayas. Gross and macroscopic appearance of intestinal tissues, as well as stomach tissues, was comparable (P < 0.05) as were total intestinal bacterial counts and activities of beta-glucuronidase. Activities of disaccharidases were not affected, neither were those of amylase (P < 0.05). Although significant differences were noted in the activity of Ca(2+) and Na(+)/K(+) ATPase brush border enzymes, no morphological alteration in the integrity of the intestinal mucosa was found. Overall, negligible effects on feed intake, body weight, and fecal output were observed (P < 0.05). Taken together, long-term exposure to diets formulated with transgenic papaya did not result in biologically important unintended effects.