A survey on the use of rugs in Australian horses

The practice of horse rugging has important implications for horse welfare and performance, but in Australia, rugging practices have not been properly documented. The objective of this study was to obtain an understanding of Australian horse rugging practices. An online survey reviewed the management of 2659 Australian horses over 12 months. Of the reported horses a total of 84.8% were rugged, although most owners (69.5%) indicated that they were unsure whether horses needed to be rugged at all. Rugging was felt by 59.8% of owners to be a requirement for horses in competition. Riding and competition were significantly associated with the use of rugs. Nearly all respondents (89.0%) felt that ‘over-rugging’ was a concern. However, 4.8% of owners would use up to 4 rugs at any one time on their horse and 21.4% of horses were still rugged in temperatures above 20°C in Australia. Many Australian horse owners (42.8%) also believe that horses feel cold if they are not rugged. Anthropomorphism when it comes to rugging horses cannot be justified as the horse has a much wider thermoneutral zone (TNZ) than humans. Australian climate, owner opinions, equestrian discipline and whether a horse is used for riding influence Australian horse rugging practices. However, current practices are based on limited available research and are not necessarily to the benefit of the horse. The major limitation was that the survey likely attracted respondents who are interested in the topic creating a self-selection bias.     

Regulation by gonadal steroids of estrogen and progesterone receptors along the reproductive tract in female lambs.

The regulation of estrogen and progesterone receptor (ER, PR) expression by estradiol (E2) and progesterone (P4) in the oviduct, uterus and cervix of female lambs was studied. The animals received three intramuscular injections of E2, P4 or vehicle with an interval of 24 h and they were slaugthered 24 h after the third injection. Determinations of ER and PR were performed by binding assays and mRNAs of ER alpha and PR by solution hybridization. High levels of ER and PR in both cervix and oviduct were found in the female lamb, differing from other mammalian species. No significant effects by either E2 or P4 treatment on ER and PR levels in the cervix and oviduct could be observed. E2 treatment increased the mRNA levels of ERa and PR more than 3-fold in the cervix, while P4 treatment increased the mRNA levels of ERa and PR in the uterus. The results show differential effects of gonadal steroids on sex steroid receptor expression along the reproductive tract in female lambs, suggesting that steroid target tissues can modulate responses to the same circulating levels of steroid hormones.     

大豆粕在海水虾类饲料上的应用(续)

~~大豆粕在海水虾类饲料上的应用(续)@Douglas E.Conklin     

Development of Digestive Enzymes in California Halibut <Emphasis Type="Italic">Paralichthys californicus</Emphasis> Larvae

California halibut Paralichthys californicus is an important commercial species with high aquaculture potential in Baja California Sur, México. To optimize the feeding process using live prey and/or inert diets, we evaluated alkaline proteases, pepsin, trypsin, chymotrypsin, leucine aminopeptidase, lipase, α-amylase, and acid and alkaline phosphatase activities on starved larvae and larvae fed live prey. Highest activities were observed for alkaline protease, trypsin, chymotrypsin, leucine aminopeptidase, and alkaline phosphatase in feeding larvae than starved larvae on day 4 after hatching. At day 5, a sizeable increase in all enzymatic activities was detected in feeding larvae. Alkaline protease, trypsin, chymotrypsin, and alkaline phosphatase decreases progressively from day 5 until day 18. At day 18, a slight pepsin activity was observed. This was considered an indicator of the start of digestive system maturation. We concluded that total enzymatic equipment for this species is complete between day 18 and 30 after hatching. Based on this evidence, early weaning from live prey to inert feed would be possible at this time.     

Evaluation of a topical treatment, alone and in combination with a detergent, for generalized demodicosis

Thirty dogs (20 treated, 10 controls) with naturally-acquired generalized demodicosis were utilized to evaluate the bio-activity and safety of a liquid concentrate formulation of amitraz, with or without the addition of a nonionic detergent. The detergent was added to the treatment mixture to enhance wetting and thereby reduce the number of treatments required to return diseased animals to a normal state. Three--six miticide treatments were topically applied to dogs at 14-day intervals, at a concentration of 250 parts per million active drug. The liquid concentrate with or without detergent, was equally effective and safe as a dermatotherapy for demodicosis; addition of the nonionic detergent grossly improved the wetting characteristics of the treatment mixture; however, it did not alter the biological activity or the safety of the therapy.