Oral fowlpox vaccination in chickens.

Chickens were given various fowlpox vaccines on food pellets--a commercial vaccine (strain M), and the same strain after a single passage on chorio-allantoic membrane or in chicken embryo fibroblasts. All three oral vaccines induced antibodies at levels similar to those induced by commercial strain M administered to the wingweb. The oral vaccine derived from chorio-allantoic membrane gave protection similar to that obtained with vaccine administered by the wingweb, but this required a thousandfold more virus.     

The effect of fatty acids in the feed on xanthine dehydrogenase activity in the Japanese quail]

The aim of the present study is to determine the effect of different fatty acids on the amino acid catabolism judged on the level of xanthine dehydrogenase (XDH). The model system of protein depletion with subsequent repletion was used in the trial consisted of Japanese quails 71 days old. In the period of protein repletion, the fatty acid (stearic, palmitic, oleic, linolenic, linoleic and lauric, respectively) was used instead of common fatty compound in the diet. Specific activities of XDH in liver, kidneys and pancreas of quails were tested dynamically from the first to the eighth day of feeding. It was demonstrated that neither lauric, palmitic nor oleic acid, respectively, had an effect on the development of the specific activity of XDH (Fig. 3). Stearic acid as a sole fatty compound in the diet however evoked reactibility of XDH in liver or in pancreas in different way as in kidneys (Fig. 4). The dynamics of the XDH development in kidneys was practically identical than that in the control. However, XDH in liver and pancreas raised statistically already from the first day of feeding. The effects of linoleic and linolenic acids on the development of specific activity of XDH were organ selective, too (Fig. 5). XDH in kidneys was shown in the same manner as in the control group. In liver and pancreas, however, the specific activity of XDH was diminished markedly just from the first day of feeding.     

Analytical methods for mycotoxins

Biological, physico-chemical and immunochemical methods are available today for solving the multiple problems which turn up in the course of mycotoxin diagnosis and mycotoxin research. In this review, selected analysis techniques are presented and their limits and possibilities are discussed. The biological methods (chicken-embryo-test, skin irritation test, cell cultures) indicate only toxicities, mostly without further specification for mycotoxins. In contrast, modern physico-chemical analysis (DC, HPLC, CLC, MS) allows the detection of defined mycotoxins in the picogram range; these methods should be employed or official and judicial purposes. The recently developed immunochemical methods (RIA, EIA) are characterized by a simple sample preparation, a short test duration and a high sensitivity; they could be used as a screening method in the course of mycotoxicological control of food and feed.     

Economic Assessment of Alternative Aquaculture Aeration Strategies

Oxygen depletion is a serious problem for the catfish industry, especially as producers attempt to increase their production intensity. Aeration, either emergency or continuous, is the most common method used to address oxygen depletion.
A risk-programming model using Target MOTAD methodology was developed to study the aquacultural producer's aeration decision-making process. Effects of stocking rate, aeration yield response and availability of labor, capital and electricity on the selection of aeration strategy were analyzed.
Continuous aeration with electric paddlewheels was most often selected as the best aeration strategy. However, as farmers become increasingly concerned with financial risk, they apply continuous aeration with pump sprayers first, then no aeration and lastly emergency aeration with tractor-powered paddlewheels. Emergency aeration was only used when: 1) electricity was not available and the producer desired a highly conservative financial strategy, and 2) the relative efficiency of continuous aeration in the field was dramatically reduced from experimental results.     

Prevalence of Toxoplasma gondii infection in raccoons.

Serum samples from 427 raccoons (93 from Pennsylvania, 45 from New Jersey, 72 from South Carolina, 68 from Virginia, 30 from Iowa, and 119 from Ohio) were evaluated for Toxoplasma gondii antibodies in dilutions of 1:25, 1:50, and 1:500. The distribution of T gondii antibody titers was less than 1:25 for 212 raccoons (49.6%), 1:25 for 34 raccoons (7.9%), 1:50 for 117 raccoons (27.4%), and greater than or equal to 1:500 for 64 raccoons (14.9%). Tissue cysts were seen in the liver, and tachyzoites were in the brain of a raccoon with abnormal neurologic signs and concurrent infection with canine distemper virus. Organisms in the liver were stained with anti-T gondii serum, and the raccoon had a T gondii titer of 1:160 in the agglutination test.     

Production and characterization of monoclonal antibodies to budgerigar fledgling disease virus major capsid protein VP.

Eleven hybridoma cell lines producing monoclonal antibodies (MAbs) against intact budgerigar fledgling disease (BFD) virions were produced and characterized. These antibodies were selected for their ability to react with BFD virions in an enzyme-linked immunosorbent assay. Each of these antibodies was reactive in the immunofluorescent detection of BFD virus-infected cells. These antibodies immunoprecipitated intact virions and specifically recognized the major capsid protein, VP1, of the dissociated virion. The MAbs were found to preferentially recognize native BFD virus capsid protein when compared with denatured virus protein. These MAbs were capable of detecting BFD virus protein in chicken embryonated cell-culture lysates by dot-blot analysis.     

Comparative susceptibility of caponized and uncaponized tom turkeys to Pasteurella multocida.

When susceptibility to virulent Pasteurella multocida was compared, there was no significant (P greater than 0.05) difference between caponized and uncaponized tom turkeys. Neither was there any significant (P greater than 0.05) difference between the surviving caponized and uncaponized toms in the development of serum anti-P. multocida antibody. However, at 28 weeks of age, the average live body weight of the caponized toms was significantly (P less than 0.05) lower than that of the uncaponized toms. Turkeys were caponized when 9 weeks old, and different groups were exposed to P. multocida when 13, 18, 23, and 28 weeks old.     

Theileria parva: the immune status of calves born of dams immunised against East Coast fever

Eight Friesian cross cows three months pregnant to a single Friesian bull were immunised against East Coast fever by infection with Theileria parva (Muguga) sporozoite stabilate and treatment with pyrrolidino-methyl tetracycline. They were challenged with the homologous stock four times before calving and a fifth time after calving, and resisted all five challenges which killed all of the five groups of five susceptible controls. Calves born to these hyperimmunised dams were fully susceptible on challenge with the same stabilate, as were susceptible cows from the same farm and their calves. In both instances the calves died three to seven days earlier than the cows which were approximately 10 times heavier. These results show that one- to two-month-old taurine calves from artificially immunised dams are not protected from experimental T parva sporozoite challenge and that there is no inherent calfhood resistance to East Coast fever.