Evaluation of in vitro and in vivo inhibitory effects of fusidic acid on Babesia and Theileria parasites

Fusidic acid known to has antibacterial, antifungal, and antimalarial activities. Fusidic acid blocks translation elongation factor G gene in Plasmodium falciparum. In the present study, the inhibitory effects of fusidic acid on the in vitro growth of bovine and equine Babesia parasites were evaluated. The inhibitory effect of fusidic acid on the in vivo growth of Babesia microti was also assessed. The in vitro growth of four Babesia species that were tested was significantly inhibited (P < 0.05) by micromolar concentrations of fusidic acid (IC₅₀ values = 144.8, 17.3, 33.3, and 56.25 μM for Babesia bovis, Babesia bigemina, Babesia caballi, and Theileria equi, respectively). Combinations of fusidic acid with diminazene aceturate synergistically potentiated its inhibitory effects in vitro on B. bovis and B. caballi. In B. microti-infected mice, fusidic acid caused significant (P < 0.05) inhibition of the growth of B. microti at the dose of 500 mg/kg BW relative to control group. These results indicate that fusidic acid might be incorporated in treatment of babesiosis.     

Prevention of intramammary infections in dairy cows by the use of a premilking teat dip method with a foaming iodophor dip agent

In this study we investigated the efficacy of premilking teat dipping with a foaming iodophor teat dip in a negative controlled field study. Incidence of new intramammary infections (IMI), incidence of clinical mastitis, influence on somatic cell count (SCC) and the characteristics of udder tissue and teats were used as parameters to evaluate clinical efficacy. Predipping was compared with a negative control using a split-udder experimental design. Right teats were predipped with a foaming disinfectant containing 0.27% iodine while left teats served as controls. The latter were conventionally cleaned with damp cloth towels and dried manually with disposable paper towels ("best cleaning practice"). All teats were dipped after milking with the same dip. There were no differences between treated and control quarters with respect to incidence of new IMI during the study period (treated quarters: 6.6% vs. untreated: 6.95%), incidence of clinical mastitis (30 cases in the treatment group vs. 39 cases in the control group) and geometric mean of SCC of quarter milk samples. Spectrum of detected pathogens was also comparable. Condition of udder tissue and teat ducts did not differ between treated and control quarters.     

Neospora caninum and Waddlia chondrophila strain 2032/99 in a septic stillborn calf

Characteristics of an intracellularly growing micro-organism isolated from an aborted bovine foetus are described. The organism replicated within cytoplasmic vacuoles, was resistant to penicillin and exhibited structural characteristics compatible with Waddlia chondrophila. An ELISA specific for Chlamydia spp., immunofluorescence tests using antibodies directed against Chlamydia spp. or Simkania negevensis, and PCR using Chlamydia-specific primers showed that the agent was distinct from Chlamydiae or S. negevensis. Determination of 16S and partial 23S ribosomal RNA gene sequences in combination with the PCR results and the morphological, antigenic and developmental characteristics provided evidence that the isolate 2032/99 can be classified as W. chondrophila or a closely related organism.     

Preliminary studies of serum acute-phase protein concentrations in hematologic and neoplastic diseases of the dog

Serum concentrations of acute-phase proteins (APPs): haptoglobin (Hp), ceruloplasmin (Cp), serum amyloid A (SAA), and C-reactive protein (CRP) were determined in healthy dogs (n = 15) and dogs with different diseases grouped as acute inflammation (I, n = 12), hematologic neoplasias (HT, including leukemia and lymphoma, n = 16), nonhematologic neoplasias (NHT, including epithelial, mesenchymal, and mixed, n = 20), and autoimmune hemolytic anemia (AIHA, n = 8). SAA and CRP were analyzed using commercially available enzyme-linked immunosorbent assay (ELISA) kits, and Hp and Cp were measured using colorimetric methods, all previously validated for use in dogs. Increased concentrations of all APPs were observed in all groups of diseased dogs, but statistical significance only was observed with Hp (I, P < .001; HT, P < .05), Cp (I, P < .05; AIHA, P < .01), and CRP (I, P < .001; HT, P < .001; AIHA, CRP P < .05). High variability in individual APPs within each group of diseases was found with no significant differences between leukemia and lymphoma as well as among different types of neoplasia. The AIHA group had smaller increases in Hp, SAA, and CRP but higher concentrations of Cp. When follow-up of individual cases was possible, a decrease in APPs generally was found in cases with favorable outcome. The results of this study suggest that neoplasia and hematologic diseases such as AIHA should be considered as possible causes of mild increases in APPs in dogs. Measurement of APPs may be helpful to assess clinical evolution and monitor treatment of these processes.     

Blood, Bull Terriers and Babesiosis: further evidence for direct transmission of Babesia gibsoni in dogs

This study reports on the epidemiology of Babesia gibsoni in American Pit Bull Terriers living in a region of western Victoria in southern Australia. Both American Pit Bull Terriers (n = 100) and other dog breeds (n = 51) were screened for B gibsoni using immunofluorescent antibody testing (IFAT) and/or polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). A questionnaire was also completed by each dog owner, ascertaining the husbandry and habits of the dogs sampled. Fourteen dogs were positive for B gibsoni using IFAT and/or PCR-RFLP and all were American Pit Bull Terriers. Dogs that were male and/or had been bitten by or were biters of other American Pit Bull Terriers were more likely to be B gibsoni positive, thus suggesting that blood-to-blood transmission contributes to the spread of this disease between dogs.     

Urethrotomy of the glans penis in three male dogs with urolithiasis

Three intact male dogs with stranguria and haematuria caused by uroliths in the penile urethra underwent urethrotomy using a novel surgical approach directly over the caudal part of the os penis because conservative procedures to resolve the obstructions had failed. Haemorrhage was minimal, and the incisions healed rapidly by second intention. Complications did not occur during the 6‐month follow‐up period. Urethrotomy directly over the os penis is straightforward, associated with few complications and holds promise for the removal of urinary calculi in the penile urethra.     

Induction of immune tolerance to caseins and whey proteins by oral intubation in mouse allergy model

This study was designed to evaluate the effect of oral tolerance of caseins (CSN) and whey proteins (WP) in alleviating the allergic response to cow's milk proteins in Swiss albino mice raised on a milk protein–free diet. Oral tolerance was induced by feeding mice with 20 mg of CSN or WP once in a day for 4 days consecutively before immunization with respective protein by intraperitoneal (i.p.) injections (20 μg 200 per μl of PBS) using 2% of alum Al(OH)₃ as adjuvant. Three weeks later, oral tolerance induction was analysed in humoral and cellular compartments of CSN‐ and WP‐fed versus saline‐fed control mice groups by measuring seric and intestinal antibody responses, mRNA abundance in splenic tissue and cytokine secretion patterns. The specific serum immunoglobulin‐E (IgE) levels were significantly suppressed (p < 0.05), while sIgA was enhanced in these groups when compared with their respective saline‐fed mice. Moreover, the mRNA levels of interferon‐γ (IFN‐γ) and interleukin‐4 (IL‐4) in both CSN‐ and WP‐tolerized mice were found to be significantly decreased, while the abundance of interleukin‐10 (IL‐10) and transforming growth factor‐β (TGF‐β) was increased significantly, as compared to respective control groups. Finally, cytokine profiles indicated a reciprocal decrease in IL‐4 and IFN‐γ versus an increase in IL‐10 secretions in supernatants of cultured splenocytes of tolerized mice. Taken together, these results clearly showed that oral administration of cows' milk caseins and whey proteins can induce significant hyposensitization in mice, with the participation of suppressor cytokines.     

Effect of feeding level on ileal and total tract digestibility of nutrients and energy from soybean meal‐based diets for piglets

A total of 36 piglets with an initial body weight (BW) of 5.6 ± 0.7 kg, fitted with simple T‐cannulas at the distal ileum, were used to evaluate the effect of three graded feeding levels (50, 75 or 100 g/kg BW^0.75 day) on apparent ileal digestibility (AID) and total tract digestibility (ATTD) of dry matter (DM), nitrogen (N) and energy, and on ATTD of organic matter (OM), ether extracts (EE), neutral detergent fibre (NDF), acid detergent fibre (ADF) and digestible (DE), metabolisable (ME) and net energy (NE) content in soybean meal (SBM)–casein–cornstarch‐based diets. The AID of DM, N and energy and ATTD of NDF, ADF and EE in the diets were not affected (p > 0.05) by the feed intake (FI) level. There was a small decrease in ATTD of DM, N (CP), OM, ash and energy, and in DE, ME and NE content in the diets (p < 0.05) with increasing FI level. The net disappearance in the large intestine (in % of ileal recovery) decreased for DM, N and energy (p < 0.05) with increasing FI level. The design of the study allowed for estimating ileal endogenous loss of N and total tract endogenous loss of ash, N and EE, for estimating corresponding true ileal and total tract digestibility values, and for estimating urinary endogenous N loss. High variability in estimates of ileal endogenous N loss and total tract endogenous losses of N, EE and ash reflects great variation in individual endogenous losses between animals. Estimation of true total tract digestibility of N, EE and ash by regression analysis was affected by their decrease in ATTD with increasing FI level, as estimates for true digestibility were lower compared to their apparent values. The present results suggest that FI level can affect both apparent and true total tract nutrient digestibility in piglets.