K. L. Goodrowe

Reproductive and genetic consequences of founding isolated lion populations

Species survival is critically dependent on reproductive performance, a complex physiological process under rigorous genetic control. Classical studies of inbreeding in laboratory animals and livestock have shown that increased homozygosity can adversely affect spermatogenesis, ovulation and perinatal mortality and morbidity1–3. For wild populations, the consequences of inbreeding depression have not been examined intensively, although our recent studies of the African cheetah revealed a striking degree of genetic uniformity4,5 combined with an extremely high incidence of structurally abnormal spermatozoa (>70%) in captive6 as well as free-ranging7 males. In this study, we report definitive evidence that the reproductive function of free-ranging mammals can be impaired as a result of demographic contraction followed by inbreeding. In an examination of three distinct lion populations (two from the Serengeti ecosystem in East Africa and a third descended from lions in the Gir Forest of western India), a direct correlation was observed between genetic variability and two physiological traits, incidence of abnormal sperm and circulating testosterone, a critical hormone for spermatogenesis.

Ovarian response to human chorionic gonadotropin or gonadotropin releasing hormone in cats in natural or induced estrus

Human chorionic gonadotropin (hOG) or gonadotropin releasing hormone (GnRH) was given alone or with repeated coital stimuli to study ovarian activity and ovulation in the domestic cat. Adult cats in natural estrus (NE) or treated with follicle stimulating hormone (FSH-P) to induce estrus (2.0 mg/d for 5 d; IE) were assigned to one of five treatments: I, mating (M) only (three times daily for the first 3 d of estrus); II, M + hOG (250 IU, i.m. on Days 2 and 3 of estrus); III M + GnRH (25 mug, i.m. on Days 2 and 3 of estrus); IV, hOG only (250 IU, i.m. on Days 2 and 3 of estrus); or V, GnRH only (25 mug on Day 2 and 3 of estrus). Overall, IE females produced a greater (P < 0.05) number of corpora lutea (7.6 +/- 0.9) and unovulated follicles (18.9 +/- 2.1) than NE cats (4.9 +/- 0.6 and 3.6 +/- 0.9, respectively). For both NE and IE females, the M + hOG treatment (II) produced a greater number (P < 0.05) of ovulations (9.1 and 13.9, respectively) than any other ovulatory regimen (I, 4.1, 6.6; III, 4.1, 7.8; IV, 4.0, 6.2; V, 4.1, 5.6, respectively). These results indicate that 1) the excessive follicle number resulting from FSH-P treatment cannot be reduced with any of the hOG or GnRH treatments tested and 2) the use of hOG with copulatory stimuli synergistically enhances the ovulatory response of cats experiencing a natural estrus or those treated with FSH-P.

SWIMMER SYNDROME IN A CLOUDED LEOPARD (NEOFELIS NEBULOSA) CUB

Abstract: A 32-day-old, hand-reared, captive-born female clouded leopard (Neofelis nebulosa) cub presented as being unable to stand, ambulate, or adduct both hind limbs. The cub exhibited hyperextension of both tarsal joints and a flattened thorax, which limited mobility to “swimmer-like” movements. Neither congenital defects nor neurologic deficits were observed during the medical examination. Radiographic examination showed the thorax was compressed dorsoventrally, but no other skeletal abnormalities were detected. Based on clinical signs, the condition was more consistent with swimmer syndrome, which has been described in young offspring of several domestic species. Over the course of 3 wk, affected limbs were treated by intensive physiotherapy, corrective bandages were applied, and thermotherapy was used to improve circulation, which resulted in a complete recovery and development of subsequent normal ambulation. It is concluded that early diagnosis and treatment of this condition led to the resolution of clinical signs, resulting in normal development of the clouded leopard cub reported here.