Abstract

A nine year old female grey seal (Halichoerus, grypus) presented with a macerated fetus protruding from the vulva. The fetus was manually extracted and a putrid smelling serosanguineous fluid was flushed from the uterus and vaginal vault. The animal was treated with a broad spectrum bacteriocidal antibiotic as the uterine flushes were continued. The animal died eleven days post dystocia. The post-mortem examination revealed a necrotizing vaginitis with extension into the peripelvic tissues, a severe diffuse cystitis and a focal gastric ulceration. The blood culture results demonstrated many Clostridium perfrinqens. Modes of therapy as well as pathological findings will be discussed.

Clinical Report

A nine year old female grey seal (Halichoerus gyrpus) was observed with vulvar bleeding 24 hours prior to abdominal contractions on 28 November 1987. This animal as well as the remainder of the grey seal females in this colony normally begin parturition in early January. Subsequently a portion of a fetus was observed protruding from the vulva in a posterior, longitudinal dorsosacral presentation- The animal continued labor without further progress of the fetus. The body was manually extracted with moderate difficulty using lubrication and obstetrical chains. Incomplete placental membranes were removed with the fetus. Approximately 2 liters of putrid smelling serosanguinous fluid exited the uterus and vaginal vault following fetal extraction.

A clinical diagnosis of abortion of a macerated fetus with secondary endometritis and a retained placenta was made. The uterus was flushed with 1 liter of sterile saline a followed by the infusion of 600 mg of gentamicin sulfate. These flushes were repeated at 72 hour intervals. Trimethoprim-sulfadiazine-b(TMP/SDZ) 24% was administered at the rate of 34 mgs of TMP/SDZ per kg body weight intramuscularly once daily for 10 days. 15mgs total dose of repeated in 72 hours.

Initially the animal's attitude improved but then slowly declined over a 10 day period. During that time the seal was anorexic. Attempts to force feed were thwarted by the animal's size and strength. Intermittently clotted blood and tissue were observed being expulsed from the vulvar vault. This was interpreted to be placental membranes.

Complete blood counts revealed a 4,950 WBC and a 45% hematocrit which rose to 14,700 and 50% respectively over 72 hours. The initial differential was 445 monocytes, 842 lymphocytes, 1336 segmented neutrophils and 2327 banded neutrophils. At 72 hours the differential was 2499 monocytes, 1470 lymphocytes and 10,731 neutrophils. Progesterone levels on day one were 6.68ng/ml and 72 hours post had fallen to 3.24ng/ml.

The vaginal culture demonstrated a beta-hemolytic Streptococus spp. and a few E. coli The blood culture grew a beta-hemolytic E. coli a Bacteroides melanogenicus and many Clostridium perfrigens. On day ten the animal was switched from TMP/SDZ to ampicillin-4. On the morning of day 11 the animal was found dead.

Pathology Report

A 140.9 kq adult female grey seal presented in good weight with a small amount of tannish material caked around the vulva. There was a multifocally extensive petechiation most pronounced in the right caudal flank and right scapular regions. A focal, rhomboid, 2x2cm ulcer was found in the gastric mucosa in the region of the cardia. The peripelvic connective and muscular tissues were crepitant. These crepitant regions contained pockets of purulent material and extended throughout the pelvic region. This included the tissues covering the pelvic bones in the proximity of the vagina. The corresponding length of vaginal mucosa was necrotic and covered with a layer of pale tan material.

The cervical tissue appeared irregular with a possible traumatic tear. Small tags of placental tissue were adhered to the endometrial surface of the right uterine horn and the right horn was larger than the left. The bladder mucosa was markedly hemorrhagic and the lumen contained small amounts of yellow, mucoid material. The mid-distal urethra was surrounded by severely hemorrhagic tissue. vaginitis with extension into the peripelvic tissues. A severe, diffuse cystitis and a focal, moderate gastric ulceration.

Histopathology supported the gross findings. There was a necrosuppurative, dissecting, severe myositis of the peripelvic tissues. Also of note were multifocally extensive pulmonary emphysematous bullae, focal renal infarcts, myocardial congestion with marked multifocal myodegeneration, adrenal corticomedullary congestion and severe dissociation of the hepatic cord cells.

The adrenal and hepatic lesions were consistent with a shock-like state. The crepitance palpated grossly in the pelvic region and the necrosuppurative myositis were consistent with a clostridial infection.

Discussion

While cases of reproductive failure in pinnipeds have been sited (1,2,3) none refer to the grey seal in particular. Historically this group of animals has been free from reproductive problems. In fact it is published that one could set a chronometer by the January 16 births of at least one grey seal cow at the New York Aquarium-3. The initial signs of labor in late November were an early indication of a reproductive problem in this female.

Clostridium perfringens was believed to be the major pathogen leading to an overwhelming infection and death. Cases of fatalities in marine mammals due to Clostridium Perfringens have been reported-4,5. There is no mention in the literature of the use of trimethoprim-sulfadiazine in pinnipeds however its use in canine and equine species is well substantiated-6. The use of TMZ/SDZ as a broad spectrum antibiotic was appropriate in retrospect since this drug's sphere of antimicrobial activity included Clostridium perfringens. The failure of the therapy can be postulated to be due to the overwhelming extent of the infection at the time that clinical signs were manifested and therapy was instituted.

Dinoprost tromethamine is a natural prostaglandin used extensively in bovine-6 for the treatment of chronic endometritis as well as to induce corpus luteum regression. Progesterone levels taken prior to and 72 hours post injection of dinoprost suggest that it may have effected or aided in the lysing of the copus luteum.

Conclusion

A nine year old female grey seal died 11 days post dystocia of a macerated fetus which was manually extracted. A postmortem exam demonstrated death was due to a severe diffuse bacterial necrotizing vaginitis with extension into the peripelvic tissues. Ante-mortem blood cultures demonstrated a Clostridium perfringens. Treatment with dinoprost tromethamine and trimethoprim-sulfaclozine while possibly of value did not after the course of the disease.

Products Used

 Gentocin Solution. Schering Co. Kenilworth, New Jersey

 Tribrissen 24% Injection- Coopers Animal Health Inc. Kansas City, Missouri

 Lutalyse. The Upjohn Co. Kalamazoo, Michigan

References

1.  1. Helle, E. 1980, Lowered reproductive capacity in female ringed seals in the Bothnian Bay Northern Baltic Sea with special reference to uterine occlusions. Ann Zool Fenn. 17:147-158.

2.  Reijnders, P.J. 1986. Reproductive failure in common seals feeding on fish from polluted coastal waters. Nature(London). 324:456-457.

3.  Sweeney, J. 1986. Reproduction. Pp. 789-791 in Fowler, M.E.(ed.). Zoo and Wild Animal Medicine, 2nd ed. W.B. Saunders Co. Philadelphia.

4.  Buck, J.D., L.L. Shepard and S. Spotte. 1987. Clostridium perfringens as the cause of death in a captive Atlantic Bottlenosed Dolphin. J. Wildlife Dis. 23: 488-491.

5.  Howard, E.B., J.O. Britt and G. Matsumoto 1983. Parasitic diseases. Pp.119-133 in Howard, E.B.(ed.). Pathobiology of Marine Mammal Disease Vol 1. CRC Press Boca Raton, Fla.

6.  Aronson C.E. (ed.). 1984. Veterinary Pharmaceuticals and Biologicals 1985/1986. Veterinary Medicine Publishing. Edwardsville, KS.