Parasites in Kentucky Thoroughbreds at necropsy: emphasis on stomach worms and tapeworms

A total of 363 Thoroughbreds (62 males, 292 females, and 9 geldings), 1 to 26 years of age, were examined at necropsy for internal parasites for about a 12-month period from February 1981 through February 1982. Emphasis was on examining the stomach for nematodes and the small intestine and cecum for tapeworms. Parasites recovered from the stomach and infection rates were: Habronema spp--immature (24%), H muscae--adult (38%), Draschia megastoma--immature (13%), D megastoma--adult (62%), and Trichostrongylus axei--adult (4%); lesions caused by D megastoma were found upon gross observation in 58% of the stomachs. The tapeworm, Anoplocephala perfoliata, was recovered from 54% of the horses; A magna was not found. There was no obvious difference in infection rates of the stomach worms and tapeworms according to age or sex of the horses. Seasonal differences were apparent only for immature Habronema spp and immature D megastoma for which infection rates began increasing in June, peaking in October, and declining thereafter. Presence of 4 additional species of parasites was recorded, but only a cursory examination was made for them. These were the large strongyles, Strongylus vulgaris, S edentatus, and S equinus, from the cecum and a filariid, Setaria spp (probably S equina), from the abdominal cavity, for which recovery rates from the horses were 8%, 8%, 1%, and 7%, respectively.     

Complications associated with the use of indwelling epidural catheters in dogs: 81 cases (1996-1999)

OBJECTIVE: To evaluate complications associated with use of indwelling epidural catheters in dogs in a clinical setting. DESIGN: Retrospective clinical study. ANIMALS: 81 client-owned dogs. PROCEDURE: Medical records were reviewed for dogs in which a 19-gauge epidural catheter was placed percutaneously at L7-S1 and advanced to the point of maximum efficacy for pain control (between L7 and T4, depending on the procedure). Catheters were used to provide perioperative epidural analgesia during surgeries that included perineal (n = 6), hind limb (33), abdominal (43), thoracic (5), forelimb (2), and cervical (1) procedures. RESULTS: Catheters were maintained in situ from 1 to 7 days (mean, 2.3 days; median, 2.0 days). Sixty-four dogs did not have complications; 17 dogs had minor complications. Catheter dislodgement was the most common complication (13/80 [16%] dogs). Catheter site contamination without inflammation developed in 2 (2.4%) dogs; inflammation at the catheter site developed in 2 (2.4%) dogs but was not related to duration of time the catheter was in place. Complications were not serious and did not require treatment other than catheter removal. Dogs that dislodged their catheters were significantly younger (mean, 2.9 years; median, 2.0 years) than other dogs (mean, 6.2 years; median, 6.0 years). Dogs that received femoral fracture repair dislodged their catheters more often (62.5%) than dogs undergoing other procedures (10.9%). CONCLUSIONS AND CLINICAL RELEVANCE: The complication rate associated with temporary epidural catheterization of dogs appears to be low, and complications generally are not serious.     

Unusual ovarian activity in a mare preceding the development of an ovarian granulosa cell tumour

An 8-year-old mare, with a foal at foot, was inseminated on foal heat with frozen semen, with the resultant pregnancy lost between days 34 and 41. The right ovary developed a large anovulatory follicle that was non-responsive to multiple doses of ovulating agents. The follicle eventually appeared to luteinise, although plasma progesterone concentrations did not reflect this. Another follicle developed, responded to GnRH and resulted in a pregnancy from frozen semen that went to term with a healthy foal. When the mare was examined after foaling, the structure on the right ovary appeared to be a granulosa cell tumour; the left ovary was smaller than normal and non-functional. Surgical removal of the right ovary before increasing photoperiod resulted in a return to function of the left ovary and a pregnancy to frozen semen on the second cycle following removal. Figures showing concentrations of inhibin, progesterone, androstenedione, oestradiol and testosterone are presented for this entire period. Unusual ovarian activity in the mare might be a prelude to the development of a granulosa cell tumour.     

Comparison of a competitive inhibition ELISA and the card agglutination test for detection of antibodies to Anaplasma marginale and Anaplasma centrale in cattle

OBJECTIVE: To compare a recently developed recombinant MSP-5 competitive inhibition ELISA with a card agglutination test for detection of antibodies to Anaplasma marginale and Anaplasma centrale in Australian cattle. MATERIALS AND METHODS: The ELISA was compared with the card agglutination test using 208 sera from cattle in Anaplasma-free herds, 86 sera from cattle experimentally infected with A marginale or A centrale and 757 sera from cattle in areas endemic for A marginale. RESULTS: The specificity of the ELISA, based on testing 208 sera from cattle in Anaplasma-free areas, was 99.5%, and the sensitivities for detection of antibodies to A marginale and A centrale in sera from the experimentally infected cattle were 98.0% and 100%, respectively. For the same sets of sera, the specificity of the card agglutination test was 98.6% and the sensitivities for detection of antibodies to A marginale and A centrale were 98.0% and 100%, respectively. For the 757 sera collected from cattle in areas endemic for A marginale, the agreement between the ELISA and the card agglutination test depended on the positive threshold selected for the ELISA. The maximum achievable agreement was 91.5% (kappa = 0.73; 95% confidence interval 0.66, 0.79). CONCLUSION: We conclude that the competitive inhibition ELISA is a useful alternative to the card agglutination test for detection of A marginale or A centrale infection in cattle. The assay should be particularly useful for epidemiological applications such as prevalence studies and control programs.     

Further investigation of equine fescue oedema induced by Mediterranean tall fescue (Lolium arundinaceum) infected with selected fungal endophytes (Epichloë coenophiala)

Abstract

AIMS

To determine if equine fescue oedema (EFO) induced by grazing Mediterranean-type tall fescue (Lolium arundinaceum) infected with selected endophytes (Epichloë coenophiala) could be prevented by treatment with the corticosteroid, methylprednisolone, and anti-histamine, cetirizine, and to determine concentrations of lolines, specifically N-acetyl norloline (NANL), in grasses grazed by horses that did and did not develop EFO.     

A retrospective study of artificial insemination of 251 mares using chilled and fixed time frozen-thawed semen

REASONS FOR PERFORMING STUDY: Historically, artificial insemination (AI) using frozen semen has been perceived to have poorer success rates and be more labour intensive than using chilled semen. A retrospective study was therefore conducted to compare the conception rate achieved by AI between chilled and frozen semen, using fixed time insemination protocols over 2 breeding seasons. HYPOTHESIS: Artificial insemination using chilled semen produces a higher conception rate than that achieved with frozen semen. METHOD: Mares (n = 251) were inseminated with either chilled (n = 112) or frozen (n = 139) semen in the 2006 and 2007 northern hemisphere breeding season. Per rectum ultrasonography of the mare's reproductive tract determined the timing of insemination, and deslorelin acetate was used to induce ovulation. Chilled semen insemination was performed using a single preovulatory dose delivered into the uterine body. Frozen semen was administered as 2 doses (pre- and post ovulation) using a deep uterine insemination technique. Pregnancy was detected ultrasonographically at 15 days post insemination. Conception rates were compared using a Chi-squared test. RESULTS: Insemination with frozen semen produced a significantly (P = 0.022) higher seasonal conception rate (82.0%) than that achieved with chilled semen (69.6%). CONCLUSIONS AND POTENTIAL RELEVANCE: Insemination with frozen semen can achieve conception rates equal to those with chilled semen, enabling the mare owner a greater selection of stallions.     

Effects of ketoprofen alone or in combination with local anesthesia during the castration of bull calves on plasma cortisol,immunological, and inflammatory responses

To determine the effects of the anti-inflammatory ketoprofen, alone or with local anesthesia (LA) during castration on cortisol, immune, and acute phase responses, 40 Friesian calves (215 +/- 3.5 kg) were assigned as follows: 1) control, 2) surgical castration (SURG), 3) SURG following ketoprofen (3 mg/kg BW i.v.; SURG + K), 4) SURG following LA (9 mL of 2% lidocaine hydrochloride to each testis; SURG + LA), or 5) SURG following LA and K (SURG + LA + K). Total cortisol response was greater (P < 0.05) in SURG, SURG + LA, and SURG + K + LA calves than in control calves and was not different between control and SURG + K calves. The interval to peak cortisol was longer (P < 0.05) for SURG + K + LA calves than for either SURG or SURG + K calves. On d 3, KLH-induced interferon-gamma production was lower (P < 0.05) in SURG calves than in control calves, whereas concanavalin A-induced interferon-gamma production was lower (P < 0.05) in all castration groups than in control. On d 1 after surgery, fibrinogen was higher (P < 0.05) in SURG and SURG + LA calves than in control calves, whereas SURG + LA + K calves had lower (P < 0.05) fibrinogen than did SURG calves. Haptoglobin was higher (P < 0.05) in SURG calves on d 1, 3, and 7 than in control calves. On d 1 after surgery, SURG + K and SURG + LA + K calves had lower (P < 0.05) haptoglobin concentrations than SURG calves, whereas SURG + K calves had lower (P < 0.05) levels than SURG calves on d 3. In conclusion, surgical castration induced a significant elevation in cortisol secretion; the rise in cortisol was reduced to control levels by the administration of ketoprofen but not local anaesthetic. Thus, systemic analgesia using ketoprofen is more effective than local anesthesia during castration to alleviate the associated stress response.