Adjuvants in veterinary vaccines: modes of action and adverse effects

Vaccine adjuvants are chemicals, microbial components, or mammalian proteins that enhance the immune response to vaccine antigens. Interest in reducing vaccine-related adverse effects and inducing specific types of immunity has led to the development of numerous new adjuvants. Adjuvants in development or in experimental and commercial vaccines include aluminum salts (alum), oil emulsions, saponins, immune-stimulating complexes (ISCOMs), liposomes, microparticles, nonionic block copolymers, derivatized polysaccharides, cytokines, and a wide variety of bacterial derivatives. The mechanisms of action of these diverse compounds vary, as does their induction of cell-mediated and antibody responses. Factors influencing the selection of an adjuvant include animal species, specific pathogen, vaccine antigen, route of immunization, and type of immunity needed.     

The effects of danofloxacin and tilmicosin on neutrophil function and lung consolidation in beef heifer calves with induced Pasteurella (Mannheimia) haemolytica pneumonia

Pneumonia caused by Pasteurella (Mannheimia) haemolytica was induced in weaned beef heifer calves, approximately 6 months of age. Calves were treated at 20 h after challenge with therapeutic doses of danofloxacin or tilmicosin. Peripheral blood neutrophils were collected at 3, 24 and 48 h after treatment. The ex vivo effects on neutrophil function, neutrophil apoptosis, and hematological parameters were examined, as was the effect on percentage lung consolidation. Neutrophil function assays included random migration under agarose, cytochrome C reduction, iodination, Staphylococcus aureus ingestion, chemotaxis, and antibody-dependent and antibody-independent cell-mediated cytotoxicity. Apoptosis was determined using a cell death detection kit. Killing was performed at 72 h after treatment. Statistical comparisons were made among the three groups of challenged-treated animals: saline, danofloxacin, and tilmicosin. Comparisons were also made between nonchallenged nontreated animals (NCH) and challenged saline-treated animals. There were no significant differences for any of the neutrophil function assays or neutrophil apoptosis among the challenged-treated groups. This suggests that danofloxacin and tilmicosin have no clinically significant effects on neutrophil function or apoptosis. There were also no significant differences in percentage lung consolidation among the challenged-treated groups. Significant differences were found between the NCH calves and the challenged saline-treated calves in several neutrophil assays, which were attributed to effects of P. haemolytica infection.     

The effects of formulation on the immunostimulatory activity of dihydroheptaprenol

Holstein steer calves received a single injection of Miglyol (Sasol Chemical Industries, Ltd.) subcutaneously as a placebo, dihydroheptaprenol (DHP) (4 mg/kg) emulsified with lecithin subcutaneously, DHP in solution in Miglyol (4 mg/kg) subcutaneously, or DHP in solution in Miglyol (4 mg/kg) intranasally. The DHP emulsified in lecithin emulsion administered subcutaneously caused a substantial increase in body temperature, total leukocyte count, total neutrophil count, neutrophil cytochrome-c reduction, and neutrophil iodination 24 hours after administration and, for some of the parameters, at 48 hours. The DHP formulation in Miglyol did not have any of these effects when administered subcutaneously or intranasally. The carrier and formulation of DHP apparently have major effects on the biologic activity of DHP.     

Abdominal pythiosis in a Bengal tiger (Panthera tigris tigris).

An adult Bengal tiger (Panthera tigris tigris) housed in an outdoor sanctuary in Florida exhibited vomiting, diarrhea, and weight loss. A clinical workup did not reveal the source of the clinical signs and antibiotic therapy was unrewarding. Radiographs revealed the presence of an abdominal mass. The tiger died during an immobilization for a follow-up clinical examination. A necropsy was performed and tissue samples of intestine and mesenteric lymph nodes were submitted for histopathologic diagnosis. A pyogranulomatous panenteritis and lymphadenitis with intralesional hyphae led to a presumptive etiologic diagnosis of intestinal/abdominal pythiosis. The diagnosis of pythiosis was confirmed by serology and immunoblotting.     

Application of bovine microsatellite markers for genetic diversity analysis of European bison (Bison bonasus)

In this study, the cross‐amplification of a commercial multiplex set of 11 cattle (Bos taurus) microsatellites was tested on a panel of 35 European bison (Bison bonasus) individuals. After polymerase chain reaction optimization, all loci cross‐amplified successfully in investigated bisons. Number of alleles and observed and expected heterozygosity per locus are in the range of 2–4, 0.086–0.629 and 0.288–0.621 respectively. The availability of a heterologous set of multiplexed microsatellite markers derived from cattle opens an avenue for collecting profound genetic data for efficient conservation management strategies of the European bison.     

Enhancement of lymphocyte blastogenesis and neutrophil function by avridine in dexamethasone-treated and nontreated cattle

The lipoidal amine, N,N-dioctadecyl-N',N'-bis (2-hydroxyethyl) propanediamine (avridine or CP 20,961), formulated in liposomes, was evaluated for its effect on leukocyte kinetics, lymphocyte blastogenesis, and polymorphonuclear leukocyte (PMN) function in dexamethasone-treated and nontreated cattle. In the 1st experiment, cattle were given avridine in a single IM injection of 0.1, 1.0, or 10 mg/kg of body weight. All doses induced swelling at the injection site, a febrile response, and a leukocytosis due to a neutrophilia. Mononuclear cell numbers were normal. All 3 groups of avridine-treated animals had a higher mean lymphocyte blastogenic response to mitogens on the 4 days after administration than did the control nontreated animals. Avridine administration was associated with an enhanced ability of PMN to ingest Staphylococcus aureus and to mediate antibody-dependent cell-mediated cytotoxicity (ADCC). The highest dose (10 mg/kg) was associated with a depression of the ability of PMN to iodinate protein. An effect of avridine on PMN random migration under agarose or nitroblue tetrazolium (NBT) reduction was not observed. In a 2nd experiment, cattle were given no treatment, 0.04 mg of dexamethasone/kg IM, or 10 mg of avridine/kg IM followed 24 hours later by 0.04 mg of dexamethasone/kg. Dexamethasone administration caused a leukocytosis due to a neutrophilia with normal mononuclear cell numbers, an enhancement of PMN random migration under agarose, and an inhibition of NBT reduction, iodination, and ADCC activity of PMN. Dexamethasone did not have a detectable effect on lymphocyte blastogenesis or on ingestion of S aureus by PMN.(ABSTRACT TRUNCATED AT 250 WORDS)     

Eine Jagderinnerung aus alter Beit

Ohne Zusammenfassung     

Leitfaden für die Bannwartenkurse im Kanton Bern. Bearbeitet im Auftrage der Forstdirektion durch F. Fankhauser,Kantonsforstmeister. Bern, 1866, J. Heuberger’s Verlag. 240 Seiten in grotz 8. Preis 20 Sgr.

Ohne Zusammenfassung     

The response of cylindrocladium conidia to soil fungistasis

Direct observation of washed conidia of Cylindrocladium scoparium on non-sterile soils, air dried and rewetted immediately before deposition of conidia, indicated that peak germination (33–58%) occurred after 24 h incubation at 26°C. Peak germination on continually moist soils was lower (18–26%) than on rewetted soils. Lysis of germ tubes and germinating conidia on continually moist soils at 26°C was evident with 48 h. Conidia did not germinate on continually moist soils at 6°C and lysis did not become apparent until 168 h. Conidia germinated at a high level (93–99%) in axenic culture in the absence of exogenous C and N sources. The inhibition of conidial germination on soils may be attributed, in part, to the presence of soil volatiles. Germination of conidia placed on washed agar disks and exposed to volatiles from four soils ranged from 51 to 86% of the no-soil controls. Addition of carbon (13 ng C per conidium as glucose) and nitrogen (65 pg N ng^?1 C as NH₄C1) nullified the inhibitory effect of the soil volatiles. Germinability assayed on a selective medium at 26°C of conidia in artificially infested soils (approximately 10⁴ conidia g^?1 soil) decreased progressively during incubation at 26°C from 1 week to 4 months. No germinable conidia were recovered from artificially infested soils after 2 months incubation at 6°C. Conidia of C. floridanum and C. crotalariae responded similarly to C. scoparium in many assays.