ABSTRACT
Background and Aim: A conventional feeding bowl is the primary method that dog owners use to feed their dogs, but this may not encourage natural behaviors and may even exacerbate unwanted behaviors. This study aimed to compare a conventional feeding bowl to a feeding toy in relation to behavior, cortisol levels, and heart rate variability (HRV). Materials and Methods: The behaviors of four dogs were recorded and analyzed while being fed using either a stainless bowl (B) or a feeding toy (T) and either alone (A) or accompanied by a dog owner (O) for 30 min with each treatment (BA, BO, TA, and TO treatments). The dogs that were fed alone with the stainless bowl (BC) or the feeding toy (TC) were fed for 15 min/day for 7 days with their treatment, and serum cortisol levels measured on the first and last days of treatment. The dogs fed by the stainless bowl (BH) or the feeding toy (TH) with the owner present for 15 min for each treatment had their heart rate (HR) and HRV recorded by Polar® H10 during feedings The results were compared using a one-way analysis of variance (ANOVA), repeated measure ANOVA, and Student's t-test. Results: The dogs spent more time eating and interacting with the feeding toys than stainless bowls. The activity of the dogs was higher when using feeding toys, particularly with the TO treatment. Cortisol levels were significantly lower on day 7 than on day 1 of the TC treatment. The dogs' HR was higher during TH treatment than during BH treatment. All HRV parameters were decreased significantly when feeding the dog with the toys. Conclusion: The results of this study support the idea that feeding enrichment supports the natural feeding behaviors of dogs as they mimic hunting and playing behaviors. This reduced unwanted behavior, cortisol levels, and HRV, and increased food consumption, eating duration, and active behaviors. The presence of the dog's owner is important because it can enhance feeding and active behaviors, and feeding enrichment can improve the dog's welfare and the dog-human relationship.
ABSTRACT
Enterovirus-71 (EV71) and coxsackievirus-A16 (CA16) frequently cause hand-foot-mouth disease (HFMD) epidemics among infants and young children. CA16 infections are usually mild, while EV71 disease may be fatal due to neurologic complications. As such, the ability to rapidly and specifically recognize EV71 is needed to facilitate proper case management and epidemic control. Accordingly, the aim of this study was to generate antibodies to EV71-virion protein-2 (VP2) by phage display technology for further use in specific detection of EV71. A recombinant peptide sequence of EV71-VP2, carrying a predicted conserved B cell epitope fused to glutathione-S-transferase (GST) (designated GST-EV71-VP2/131-160), was produced. The fusion protein was used as bait in in-solution biopanning to separate protein-bound phages from a murine scFv (MuscFv) phage display library constructed from an immunoglobulin gene repertoire from naïve ICR mice. Three phage-transformed E. coli clones (clones 63, 82, and 83) produced MuscFvs that bound to the GST-EV71-VP2/131-160 peptide. The MuscFv of clone 83 (MuscFv83), which produced the highest ELISA signal to the target antigen, was further tested. MuscFv83 also bound to full-length EV71-VP2 and EV71 particles, but did not bind to GST, full-length EV71-VP1, or the antigenically related CA16. MuscFv83 could be a suitable reagent for rapid antigen-based immunoassay, such as immunochromatography (ICT), for the specific detection and/or diagnosis of EV71 infection as well as epidemic surveillance.
