Antioxidant systems and lymphocyte proliferation in the horse,sheep and dog

To better define the species-specific antioxidant systems and to ascertain the influence of the intracellular redox status on the immune system of different animal species, we determined lymphocyte glutathione peroxidase (GSHPx) activity, plasmatic glutathione levels (GSH) and the effect of H2O2 on the responsiveness of lymphocytes to proliferative stimuli. Among the three species considered, sheep presented the lowest plasmatic GSH and the highest lymphocyte GSHPx activity. On the contrary, dogs showed an inverted pattern (high GSH - low GSHPx). Horses displayed intermediate values for both parameters analysed. The effect of H2O2 on the proliferative capacity of lymphocytes was the same for all three species; the 200 microM dose in particular was strongly inhibiting. Each species, however, showed different rates of inhibition: sheep exhibited the highest sensitivity to the antiproliferative effect of H2O2. Our results confirmed that high H2O2 concentrations (200 microM) are noxious for the cellular functions of all animals; however this effect is mediated by a rigorously species-specific relationship between the intracellular reactive oxygen species (ROS) and the molecular systems involved in cell proliferation.     

Effect of 1-24ACTH administration on sheep blood granulocyte functions

The objective of the present study was to determine the efficiency of blood neutrophils (PMN) taken from sheep during acute stress. Ten healthy Charolle sheep were sampled before treatment (T0) and 1 (T1), 2 (T2), 24 (T24) and 48 (T48) hours after 1-24ACTH administration. Ten sheep serving as the controls were sampled at the same time intervals, using saline solution instead of 1-24ACTH. At each time sampling, rectal temperature, heart rate, cortisol, glucose, non-esterified fatty acids (NEFA), total and differential leukocyte counts were evaluated. PMN were isolated after centrifugation of whole blood and hypotonic lysis of RBC. Chemotaxis was evaluated on a modified Boyden chamber using a nitrate cellulose filter and both Zymosan activated serum (ZAS) and interleukin-8 (IL-8) as chemoattractants. Phagocytosis was measured using both non-opsonized latex beads and fluoresceinated yeasts opsonized with homologous serum. Superoxide (O(-)2) production was evaluated by measuring superoxide dismutase-inhibitable reduction of ferricytochrome C, and adherence by a colorimetric assay of acid phosphatase activity of adherent cells. The administration of 1-24ACTH induced an acute stress reaction, indicated by the presence of clinical, biochemical and hematological changes. Adherence significantly increased from T0 to T2 in treated sheep. This might be responsible for the depression of non-specific immunity in stressed animals. Studies using stressors other than 1-24 ACTH are needed to verify the influence of other components of the stress reaction on PMN functions.     

Feline leishmaniosis due to Leishmania infantum in Italy

A case of leishmaniosis in domestic cats (Felis catus domesticus) is described. The subject showed a nodular lesion on the eyelid. The diagnosis was achieved by serological, parasitological, and light and electron microscopic investigations. By molecular techniques the aetiological agent was identified as belonging to Leishmania infantum, the species implicated in human and canine leishmaniosis in southern Europe. A preliminary study on the prevalence of asymptomatic feline leishmaniosis, performed in the areas where the infected cat was identified, revealed a low seroprevalence of infection: only 1 (0.9%) of the 110 cat sera examined by indirect fluorescent antibody test was positive for anti-Leishmania antibodies. Because clinical signs in feline leishmaniosis are unspecific and similar to those observed in other diseases commonly found in this species, leishmaniosis must be added to the differential diagnosis by feline veterinary practitioners and adequate serologic and histopathologic investigations must be performed in endemic areas.     

Restriction endonuclease and monoclonal antibody analysis of Brazilian isolates of bovine herpesviruses types 1 and 5

Twelve Brazilian isolates and three reference strains of bovine herpesviruses (BHVs) were subjected to restriction endonuclease analysis (REA) and monoclonal antibody (MAb) analysis. Viral DNA was cleaved with BamHI, BstEII, EcoRI, HindIII and PstI. The monoclonal antibody panel allowed the differentiation between types 1 and 5 viruses, while REA with BstEII and HindIII showed the distinction between BHV-1 and -5 subtypes. Typical 1.1 and 1.2a patterns were observed with two isolates from respiratory disease. An isolate from semen of a clinically healthy bull displayed 1.2b profile, whereas another displayed a clear 5a pattern, which was never reported before. Seven out of nine Brazilian type 5 (BHV-5) isolates displayed REA patterns similar to the Australian BHV-5 strain N569 (BHV-5a), and differing from the Argentinean A663 strain (BHV-5b) virus. Another two BHV-5 isolates, which displayed an unusual MAb pattern of reactivity, showed a BstEII profile different from both reference strains of BHV-5. These two viruses were considered BHV-5 "non-a/non-b" subtype.     

Seroepidemiology of Brucella abortus infection in bovids in Sri Lanka

From 1992 to 1995, 0.15% (n=3916) of the bovids (cattle and buffalo) in Sri Lanka were sampled, using a multi-stage sampling procedure. Serum antibodies for Brucella abortus were detected using the indirect enzyme-linked immunosorbent assay (ELISA). The age, the agroecological zone and the management system practiced in the farms of the sampled bovids were studied as risk factors for seropositivity.The overall seroprevalence of brucellosis in cattle was 4.7% (n=3076) and 4.2% in buffaloes (n=840). Bovids that were over 3 years of age, from the dry zone (annual rainfall 20-35 in.), and reared under an extensive management system had higher odds of being seropositive. Bovids from the dry zone were at approximately six times higher odds of being seropositive even after controlling for the possible effects of age and management system. Approximately 75% of the seropositive males were from the dry zone. Most bovids (84%) from the dry zone in this study were reared under an extensive management system (free grazing) which allows unrestricted contact between animals. These factors may have contributed to the spread of brucellosis in bovids in the dry zone.This infection might be an important cause of abortion in bovids in Sri Lanka. However, there is also evidence of other causes for abortion, repeat breeding and retained placenta.     

Variability of resistance in goats infected with Haemonchus contortus in Brazil

The variability between and within breeds with respect to nematode egg counts (EPG), packed cell volume (PCV) and hemoglobin (Hb) was studied in 36 yearling female goats of the Caninde (15), Bhuj (6) and Anglo-Nubian (15) breeds, exposed to Haemonchus contortus. Nematode-free goats were turned to a contaminated paddock in late February. From then on, fecal egg per gram counts (EPG), packed cell volume (PCV) and hemoglobin (Hb) were determined at 2-week intervals up to Week 18. The EPG, transformed as [log(EPG + 75)], varied (P < 0.01) between goats within breeds and between weeks of exposure, but not between goat breeds (P > 0.05). PCV and Hb were affected by goat breeds (P < 0.05), by goats within breeds (P < 0.01) and by weeks of exposure (P < 0.01). Anglo-Nubians had higher (P < 0.01) PCV and Hb than Caninde; Bhuj had intermediate values. There were two EPG rises; one between Weeks 6 and 10 and the other between Weeks 14 and 16. The within breed variability was marked during the EPG rise on Week 6, when individual egg counts ranged from 130 to 2500. The EPG rises coincided with drops in Hb. PCV presented a similar trend, though not as marked. Haemonchus was responsible for more than 95% of nematode eggs counted. Considering the goat as experimental unit, the correlation coefficients (r) were: -0.45, P = 0.0064, between log(EPG + 75) and PCV; and -0.53, P = 0.0009, between log(EPG + 75) and Hb. The negative correlation between egg counts and blood values suggested breed differences in PCV and Hb were related to resistance to H. contortus infection and/or to its effects.     

Effect of floor cooling on performance of lactating sows during summer

Forty Landrace × Large White lactating sows were used to evaluate the effects of cooling of the floor when maintained under high temperature conditions during summer on their productive and reproductive performance. The sows were allocated in a completely randomized design with two treatments with 20 replicates according to parity number and body weight, with each animal being considered an experimental unit. The treatments consisted of cooling of the floor under the sow with water circulation at about 17 °C and no cooling. The resulting temperatures of the floor were 27.6 and 35.8 °C for the cooled and the control treatments, respectively. The sows from both treatments were exposed to average maximum and minimum environmental temperatures of 26.9 and 20.8 °C, respectively. Sows maintained on a cooled floor had a higher feed intake (6.47 vs. 5.61 kg/day; P < 0.01). Despite this higher intake, sows maintained on a cooled floor had higher body weight and body protein losses during the lactation period (P < 0.01) in connection with a higher milk yield and subsequent growth of the litter (2280 vs. 1798 g/day; P < 0.01). There was an effect of treatment on rectal temperature, surface temperatures and respiratory rate (P < 0.01) with lower values in sows submitted to floor cooling. It is concluded that floor cooling under the lactating sow improves its productive and reproductive performance, as well as the performance of its litter.     

Electro-acupuncture and Chinese herbs for treatment of cervical intervertebral disk disease in a dog

A non-ambulatory dog with tetraparesis following a pain episode that had evolved over 2 months was submitted for medical treatment and diagnosed with intervertebral disk disease at C3-C4 and dorsal extradural compression at C1-C2 and C3-C4 using myelography and computed tomography. The dog experienced ambulation recovery after 15 days of treatment with only electroacupuncture and Chinese herbal medicine, with marked improvement occurring after only 10 treatments. Six months of follow-up demonstrated that the dog was stable and had no recurrence of symptoms. Therefore, it was concluded that the combination of electroacupuncture and Chinese herbal medicine was responsible for motor rehabilitation.     

Renal cell carcinoma with bone metaplasia in a horse

A case of renal tubular carcinoma with bone metaplasia is reported in a 20-year-old male, mixed breed horse having a history of weight loss and hematuria. This report includes the clinical signs, macroscopic and microscopic lesions, and the immunohistochemical findings of this neoplasm.