Veterinarno-meditsinski nauki最新文献

Studied was the amount of the total protein, the urea, and the blood sugar in both normal calves and calves that were affected with enteritis with frequent isolates of pathogenic Escherichia coli strains and corona and rotaviruses. Stated are the normal values of these indices in calves aged from 1 to 6 days as well as from 7 to 15 days. It was found that with diarrhea-affected calves there were hypoproteinaemia, rise of urea, and very commonly encountered drop of blood sugar in the course of the diseases.

Tested was the activity of linkomycin hydrochloride at the rate of 820 IU/mg. The LD50 of the preparation was found to exceed 12.0 g/kg body mass at intracrop application to broiler birds. When offered with the drinking water or the feed in amounts that were 3 to 5 times higher than the therapeutic ones for broilers in the course of 45 days it did not cause mortality nor induced changes in the white and red blood cell counts, in the total protein, and in the levels of urea, blood sugar, AlT, and AcT. Neither were there any structural changes in the internal organs. Upon the single intracrop treatment of broilers with linkomycin at 50 and 100 mg/kg most of the amount introduced was established in the blood serum at the second hour and up to the 6th and 8th hour, respectively. Studies on the effect of age on the serum concentrations at this route of introduction revealed that the preparation was absorbed at higher rates in the broilers than in the layers, while with the persistence of the levels there were no essential differences. At the single oral administration with broilers in amounts of 100 mg/kg linkomycin was chiefly retained in the kidneys, liver, and lungs as well in the content of the small and large intestines. At intracrop application to layers in doses of 100 mg/kg in the course of 7 days the antibiotic was excreted with the eggs at the time of treatment and in the course of 4 days later in bacteriostatic concentrations of 0.6-5.9 micrograms/cm3.

An experiment was carried out ascertain the effect of a corn embryo, derived in a wet method, on the process of digestion in sheep. It was established that sheep digestion was considerably better after the including of a corn embryo in their ration. The coefficient of the food substances digestion in the forage for the sheep, ration with the addition of a corn embryo increased at an average for fat with 25.04%, for mineral substances--12.4%, for the row protein--7.9%, for row fibrins--7.56%. The nitrogen utilisation in the animals during the second period was considerably better.

It was established, that LD50 of rifamycin SV--sodium salt, produced by the Research Institute on Microbiological Industry--Razgrad (People's Republic of Bulgaria)--RM, at p.o. applying on albino mice, albino rats and broilers is correspondingly greater than 4100.0 mg/kg m., greater than 5740.0 mg/kg m. and 1951.6 (1355.5 divided by 2810.1) mg/kg m. and at s. c. introducing into albino mice--815.9 (756.9 divided by 879.9) mg/kg m. From the prepared on the basis of RM-4 intramammary medicaments--RM-1, RM-2 and RM-3 for lactating cows and RM-4 for cows in the dry period, a good bearing have RM-1, RM-3 and RM-4. RM-1, RM-2 and RM-3, applied intracisternally a single time on lactating cows, and RM-4 on cows in the dry period, create antimicrobial levels with duration correspondingly 168, 72 and 48 h, and 35 days. RM almost does not penetrate in the neighbouring not treated quarters. Appropriate medicament for the lactating cows with average duration of emission is RM-3 (term of action 96 h) and for cows in the dry period RM-4 when applied 35 days before the calving.

High-titer, specific serum against porcine parvovirus was obtained via hyperimmunization of rabbits, with the use of a Bulgarian isolate that had been partially purified after a known, modified technique. A specific, high-titer conjugate was produced for the immunofluorescence diagnosis of porcine parvoviruses. The microscopic observation of the lamellae of cell cultures, treated with the conjugate, revealed the presence of a specific, typically granulated perinuclear (mostly unilaterally) and, in some cases nuclear fluorescence--at negative reaction in the control preparations. Immunofluorescent light was also established in cell cultures infected with the virus at highest dilution. It showed that immunofluorescence microscopy could be employed to demonstrate even the lowest amounts of the virus.

The survival rate was followed up of S. typhimurium, S. enteritidis, S. aureus, and E. coli in the organs of M. galloprovincialis L. in experimental conditions. A vat was used with 30 mussels in 10 l of sea water contaminated with 10 cm3 broth culture in conc. of 2.10(4) bacterial cells per cub. cm. The water was changed at 24-hour intervals. Microbiologic studies were carried out of the gills, liver, and meat of the mussels and of the sampled sea water. Lowest survival rate showed S. aureus--up to the second day, S. typhimurium and S. orientalis--up to the 4th days (in the gills only), and E. coli--up to the sixth day (in the gills and liver). None of the experimental strains to the sixth day (in the gills and liver). None of the experimental strains was isolated from the meat. With regard to the periods of investigation cited M. galloprovincialis L. could play the role of a carrier, resp. vector of the infection and could bring about a disease after consumption. Stated is the important part played by mussels as biofilter, and, at the same time, as source of pathogenic bacterial microflora.

The effect was tested under laboratory in vitro conditions of eight antibiotics in media for thawing pelleted bull semen. It was found that the addition of antibiotics during the process of reanimation had no unfavourable impact on the motility of spermatozoa. Upon storage in water bath (39 degrees C) in the course of six hours gentamycin, amoxicillin, kanamycin, and polymixin preserved the semen cells and enhanced their survival rate at the same level as that of the control medium with no antibiotic. The combination of penicillin and streptomycin lowered 2.5 times spermatozoal motility. Worst was the survival rate of spermatozoa when the medium was supplemented with oxytetracycline and chloramphenicol. It was also found that best sanitation qualities with regard to the microflora in semen had gentamycin, which, at that did not produce any negative effect on the rate of survival. The conception rate of cows inseminated with semen treated with gentamycin at thawing was shown to be 15.3 per cent higher, and when treated with the combination of penicillin and streptomycin it was 3.0 per cent higher at first insemination than that of the control group of animals inseminated with semen with no antibiotic supplement.

Investigations were carried out with two groups of cows at first lactation to elucidate the effect of low rate vacuum on the health status of the mammary gland. The clinical, cytologic, and microbiologic studies were performed in dynamic. It was found that the milking of cows with the use of 39.9 kPa vacuum produced a negative effect on the normal udder. It led to secretory troubles, subclinical mastitis, and latent infection.

A total of 25,561 samples from swine (cadavers, internal organs, rectal swabs, feed, and washings of premises) were investigated microbiologically over the 1981-1985 period via routinely employed methods for the isolation and typing of Salmonella organisms, following the Kauffmann-White pattern. Tested was the susceptibility of 411 strains by the disk-diffusion method, using drugs of the general practice, and the results were recorded after Bauer. In 5.32 per cent of the samples 19 Salmonella serotypes of the B. C. D, and E groups were isolated. Greatest in the etiology of salmonelloses was still the relative share of S. cholerae suis (85.22%), represented by the two-phase var. america and the autochthonous var. kunzendorf. Second ranked S. typhimurium--5.14%, followed by S. agona--2.20%, S. menden--1.25%, S. thompson--1.18%, S. derby--1.10%, S. bovis-morbificans--0.81%, and others. A change was ascertained in the serotypes isolated from pigs with regard to the exotic types. Sensitive to gentamycin proved 89.9%, to chloramphenicol--79.1%, to carbenicillin--71%, to kanamycin--70%, etc; 75% were resistant to ampicillin, 54.6%--to streptomycin, 51.3%--to tetracycline, and 33.8%--to furazolidone.

The in vitro and in vivo solubility of ocular drug lamellae, containing 1.5 and 3 mg gentamycin sulphate, was followed up. It was found that those that contained lower amount of the antibiotic disintegrated in the eyes of rabbits, lambs, and sheep for 30-40 minutes, while lamellae having 3 mg gentamycin disintegrated for 45-50 minutes. It is stated that such ocular lamellae are well tolerated by the conjunctiva of the animal species referred to. With the application of one lamella with 3 mg gentamycin sulphate therapeutic concentrations of the antibiotic in the lacrimal secretion are found up to the 24 th hour with cows, sheep, and lambs, and up to the 48h hour with rabbits.