Evaluation of oral and subcutaneous delivery of an experimental canarypox recombinant canine distemper vaccine in the Siberian polecat (Mustela eversmanni).

We assessed the safety and efficacy of an experimental canarypox-vectored recombinant canine distemper virus (CDV) subunit vaccine in the Siberian polecat (Mustela eversmanni), a close relative of the black-footed ferret, (M. nigripes), an endangered species that is highly susceptible to the virus. Siberian polecats were randomized into six treatment groups. Recombinant canine distemper vaccine was administered s.c. at three dose levels (10(4.5), 10(5.0), and 10(5.5) plaque-forming units [PFU] per dose) and was administered orally by spraying the vaccine into the oropharnyx at two dose levels (10(5.5), 10(8.0) PFU per dose). The sixth group of control animals was not vaccinated. For both routes of administration, two 1-ml doses of reconstituted vaccine were delivered 4 wk apart, followed by live virus challenge 3 wk after the second vaccination. During the challenge, Synder Hill test strain CDV obtained from the National Veterinary Services Laboratory in Ames, Iowa, was administered i.p. Serial blood samples for CDV serology were collected immediately before vaccination and challenge, and 10, 15, and 20 days after challenge. Clinical signs and body weights were recorded up to 32 days after challenge. The survival rate in animals receiving vaccine at the highest oral dose (10(8.0) PFU per dose) was 83.3%. Survival rate was 50.0% in the high s.c. and 60.0% in the medium s.c. groups. All animals in the low-s.c. dose, low-oral dose, and control groups died after exposure. Vaccine dose overall (oral and s.c.) and dose in response to s.c. administration when considered alone were significant predictors of survival (P = 0.006 and P = 0.04, respectively). Among the polecats challenged with virulent virus, those that died became sick sooner than those that survived. Animals that died lost significantly more weight during the 10 days after challenge than did animals that survived (P = 0.02). Survival rates did not differ by sex, founder female status, or breeding pedigree in any of the treatment groups. Survival rates were higher in animals with increasing serum neutralization titers (P = 0.027). This study demonstrates the efficacy of oral delivery of a recombinant CDV vaccine in the Siberian polecat. Further studies are needed to evaluate the safety and efficacy of vectored recombinant vaccines in highly susceptible species and especially in those species in which vaccination with modified live CDV has led to disease.     

Measurement and clinical significance of equine fetal protein in pregnant mares serum

An assay for the determination of the concentration of an equine fetal protein (EQFP) in pregnant mares serum was developed and used to quantitate more than 2000 serum samples from Thoroughbred mares during pregnancy. The concentration of EQFP increased throughout pregnancy. Mares with unproblematic (normal) pregnancies were used to establish the reference values at given gestational ages (GA). Mares with pregnancy failures (n=58) were found to have EQFP concentrations outside the reference values established at given GA's; 10 were high and 48 were low. Twin pregnancies (n=21), placentitis and impending abortion (n=71) were associated with elevated concentration. Twin pregnancies were detected by elevated EQFP concentration, in one case as early as 12 days after breeding.     

Epistaxis in two horses with dacryohemorrhea.

Unilateral epistaxis in 2 horses was caused by inflammation of the distal portion of the lacrimal system. The origin of epistaxis was identified during physical examination by observing hemorrhage emanating from the nasal opening of the nasolacrimal duct. Dacryohemorrhea caused by bacterial infection was successfully treated with antibacterial drugs administered systemically and instilled into the lacrimal system.     

Isolation and characterization of lymphocytes from bovine intestinal epithelium and lamina propria

The lymphocyte populations of the bovine gut lamina proprial (LP) and epithelial tissues were isolated and characterized with respect to cells bearing surface and cytoplasmic immunoglobulin (Ig). Functional characteristics of cells from the two tissues, including responsiveness to Concanavalin A (Con A), anti-bovine immunoglobulin (anti-Ig), Con A supernatants of bovine peripheral blood lymphocytes (bConA sup) and recombinant human IL-2 (rhIL-2), were also assessed. Less than 1% of the mononuclear cells in the epithelial tissue (IEL) stained for cytoplasmic Ig, and 9% stained positively for surface Ig. IEL did not proliferate in response to anti-Ig, although cells of this population did respond to Con A, bConA sup, and rhIL-2. Twenty-seven percent of bovine gut LP lymphocytes stained for surface Ig, while 39% of these cells were positive for cytoplasmic Ig. LP lymphocytes proliferated in response to all four stimulants used, Con A, anti-Ig, bConA sup and rhIL-2.     

Intraoperative pain responses following intraovarian versus mesovarian injection of lidocaine in mares undergoing laparoscopic ovariectomy

OBJECTIVE: To compare intraoperative pain responses following intraovarian versus mesovarian injection of lidocaine in mares undergoing laparoscopic ovariectomy. DESIGN: Randomized controlled trial. ANIMALS: 15 mares between 4 and 20 years old. PROCEDURE: Standard bilateral laparoscopic ovariectomy was performed. Prior to manipulation of the ovary, 2% lidocaine (10 mL) was injected into the ovary and saline (0.9% NaCI) solution (10 mL) was injected into the mesovarium on 1 side, with saline solution (10 mL) injected into the ovary and 2% lidocaine (10 mL) injected into the mesovarium on the other side. Presence (yes vs no) and severity (visual analogue scale) of pain were scored at 5 times (grasping of the ovary, dissection of the mesosalpinx, tightening of the first loop ligature, tightening of the second loop ligature, and transection of the ovarian pedicle) by 2 individuals blinded to treatment and each other's observations. RESULTS: During 4 of the 5 observation periods, significantly fewer mares had signs of pain following mesovarian injection of lidocaine, and during 2 of the 5 observation periods, visual analogue scale score was significantly lower. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that mesovarian injection of lidocaine is associated with significantly lower pain responses, compared with intraovarian injection, in horses undergoing laparoscopic ovariectomy.