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.