Distribution of kanamycin in ocular tissues of calves.

The ocular distribution of kanamycin following intramuscular, bulbar subconjunctival injection, or after constant rate intravenous infusion to calves was studied. Steady-state plasma concentrations of kanamycin were achieved in either normal calves, or in those experimentally infected with Moraxella bovis, and the concentrations of kanamycin in the serum, aqueous humor, vitreous body, tears, and the ocular tissues were measured. Kanamycin was not detected in the retina, lens, vitreous body, or the aqueous humor of any eyes, but the concentration of drug in the tears, conjunctiva, cornea and the orbital lacrimal gland of these calves ranged between 18 and 21% of that in serum.

Correlation of macrophage migration-inhibition factor and protection from challenge exposure in calves vaccinated with Salmonella typhimurium.

Migration of bovine macrophages under agarose was used to assess cellular immunity in 7 nonvaccinated calves and 9 calves vaccinated with Salmonella typhimurium. The 9 vaccinated calves were allotted to 4 groups. Group I calves were vaccinated twice orally with small doses of virulent S typhimurium; group II calves were vaccinated twice orally with genetically altered aromatic-dependent (aro-) S typhimurium SL3261; group III calves were vaccinated twice IM with small doses of virulent S typhimurium; and group IV calves were vaccinated twice IM with aro- S typhimurium SL1479.

Diffusion in gel-enzyme linked immunosorbent assay (DIG-ELISA) to record the immunoglobulin response of calves vaccinated with Salmonella.

A diffusion in gel-enzyme linked immunosorbent assay (DIG-ELISA) was used to record immunoglobulin development of colostrum-fed calves vaccinated with aromatic dependent (aro-) Salmonella and challenged with either the homologous as a heterologous serotype. IgG was detected by using a peroxidase conjugated rabbit antibovine IgG, whereas IgM and IgA were measured using a double sandwich technique. Although IgG levels to Salmonella endotoxins increased after exposure to Salmonella, they were found to be high in many calves prior to vaccination.

Aromatic-dependent Salmonella dublin as a parenteral modified live vaccine for calves.

A virulent Salmonella dublin isolate was made histidine-requiring (his-) to allow recognition. The his- derivative, SL1367 (still calf-virulent), was then given by transduction and mutation, a transposon-generated non-reverting aromatic biosynthesis (aro) defect; this defect caused loss of virulence for the mouse. The his- aro- derivative strain, SL1438, was effective as a live vaccine in mice.

Vaccination of calves against Salmonella dublin with aromatic-dependent Salmonella typhimurium.

Ten Holstein calves were divided into 2 groups. Five calves served as nonvaccinated controls, and 5 calves were vaccinated IM at 2 and 3 weeks of age with 10(9) aromatic-dependent (aro-) Salmonella typhimurium strain SL1479 containing O antigens 1, 4, 12. Serious adverse reactions to vaccination were not observed in the calves.

Relationship of cutaneous delayed hypersensitivity to protection from challenge exposure with Salmonella typhimurium in calves.

The purpose of this investigation was to relate cutaneous delayed hypersensitivity reactions to the degree of immunity induced in calves given a live virulent or a modified-live strain of Salmonella typhimurium. Calves were placed into 1 of 5 groups on the basis of the vaccinal strain given and route of the vaccination: (I) nonvaccinated controls, (II) vaccinated twice by IM inoculation with small doses of the live virulent strain, (III) vaccinated (IM) twice with the modified-live strain, (IV) vaccinated (orally) twice with the modified-live strains, and (V) vaccinated (IM, and then orally) twice with the modified-live strain. Skin testing was performed by intradermal injection of fragmented S typhimurium as antigen.

Aromatic-dependent Salmonella typhimurium as modified live vaccines for calves.

Strains of Salmonella sp with complete nonreverting aromatic biosynthesis (aro) defects are expected to be nonvirulent, in respect to invasive infection, because they need the aromatic metabolites paraaminobenzoate (for making folate) and dihydroxybenzoate (for making enterochelin) which are not available in host tissues. Derivatives with transposon-generated complete nonreverting aro-defects were prepared from 3 mouse-virulent strains of S typhimurium, namely, FIRN, WRAY, and UCD. The latter 2 parent strains originally were isolated from calves and are known to be calf-virulent.

Salmonellosis in a group of ponies: failure to identify a chronic active carrier.

Three of 33 ponies died after the herd had been moved to a new environment 3 months earlier. One mare died without premonitory signs of illness. Shortly thereafter, a 5-day-old foal and a 2-year-old gelding died after brief illness.

Bovine salmonellosis: experimental production and characterization of the disease in calves, using oral challenge with Salmonella typhimurium.

A highly virulent strain of Salmonella tyhimurium was given orally to produce disease experimentally in 21 normal colostrum-fed calves 3 to 9 weeks old. The challenge inoculum varied from 10(4) to 10(11) organisms. The disease was characterized by fever, depressed attitude, and decreased appetite.

Prevalence and epizootiology of equine salmonellosis.

Feces from 1,451 horses entering a veterinary hospital over a 13-month period were cultured for salmonella. A total of 46 horses (3.2%) yielded 1 or more salmonella-positive fecal cultures.

Intoxication of cattle with sodium bromide-contaminated feed.

Five concentrations of bromide ion, sodium bromide, were incorporated into a pelleted ration and fed to 5 groups of cattle for 49 days. Another group of cattle was fed volunteer oat hay cut from a field that had been fumigated with methyl bromide. On analysis, the hay contained between 6,800 and 8,400 parts per million of bromide ion.

Hematology of the neonatal calf. III. Frequency of congenital iron deficiency anemia.

The hematocrits of 258 Holstein-Friesian and Jersey calves were determined during the first 3 days following birth. Hematocrit values of 25% or less were observed in 15.8% of the calves and hematocrits of 20% or less were observed in 6.

Hematology of the neonatal calf. II. Response associated with acute enteric infections, gram-negative septicemia, and experimental endotoxemia.

The hematological responses of neonatal calves with acute enteric infections were compared to the responses of calves with septicemia and experimentally induced endotoxemia. The mean hematocrit of septicemic calves (45.0% +/- 7.