Widespread retinal degenerative disease mutation (rdAc) discovered among a large number of popular cat breeds.

The recent discovery of a mutational variant in the CEP290 gene (CEP290: IVS50+9T>G), conferring recessive retinal degeneration in Abyssinian and Somali (long-haired Abyssinian) cats (rdAc) prompted a survey among 41 cat breeds (846 individuals) to assess the incidence, frequency and clinical consequence of rdAc. The rdAc allele displayed widespread distribution, observed in 16/43 (37%) breeds, exhibiting a high allele frequency (∼33%) in North American and European Siamese populations. Clinical evaluations demonstrated high concordance between rdAc pathology and the CEP290 (IVS50+9T>G) homozygous genotype (P=1.1E-6), with clinical disease similar to affected Abyssinians/Somalis. This retinal degeneration has not been reported in breeds other than the Abyssinian/Somali and poses a significant health risk particularly in the Siamese breed group. Alertness of the veterinary community and the present availability of commercial diagnostic testing could synergistically enable breeders to reduce the incidence of rdAc blindness in pure-bred cat populations.

Chromosome painting shows that skunks (Mephitidae, Carnivora) have highly rearranged karyotypes.

The karyotypic relationships of skunks (Mephitidae) with other major clades of carnivores are not yet established. Here, multi-directional chromosome painting was used to reveal the karyological relationships among skunks and between Mephitidae (skunks) and Procyonidae (raccoons). Representative species from three genera of Mephitidae (Mephitis mephitis, 2n = 50; Mephitis macroura, 2n = 50; Conepatus leuconotus, 2n = 46; Spilogale gracilis, 2n = 60) and one species of Procyonidae (Procyon lotor, 2n = 38) were studied. Chromosomal homology was mapped by hybridization of five sets of whole-chromosome paints derived from stone marten (Martes foina, 2n = 38), cat, skunks (M. mephitis; M. macroura) and human. The karyotype of the raccoon is highly conserved and identical to the hypothetical ancestral musteloid karyotype, suggesting that procyonids have a particular importance for establishing the karyological evolution within the caniforms. Ten fission events and five fusion events are necessary to generate the ancestral skunk karyotype from the ancestral carnivore karyotype. Our results show that Mephitidae joins Canidae and Ursidae as the third family of carnivores that are characterized by a high rate of karyotype evolution. Shared derived chromosomal fusion of stone marten chromosomes 6 and 14 phylogenetically links the American hog-nosed skunk and eastern spotted skunk.

Frequent transmission of immunodeficiency viruses among bobcats and pumas.

With the exception of human immunodeficiency virus (HIV), which emerged in humans after cross-species transmissions of simian immunodeficiency viruses from nonhuman primates, immunodeficiency viruses of the family Lentiviridae represent species-specific viruses that rarely cross species barriers to infect new hosts. Among the Felidae, numerous immunodeficiency-like lentiviruses have been documented, but only a few cross-species transmissions have been recorded, and these have not been perpetuated in the recipient species. Lentivirus seroprevalence was determined for 79 bobcats (Lynx rufus) and 31 pumas (Puma concolor) from well-defined populations in Southern California. Partial genomic sequences were subsequently obtained from 18 and 12 seropositive bobcats and pumas, respectively. Genotypes were analyzed for phylogenic relatedness and genotypic composition among the study set and archived feline lentivirus sequences. This investigation of feline immunodeficiency virus infection in bobcats and pumas of Southern California provides evidence that cross-species infection has occurred frequently among these animals. The data suggest that transmission has occurred in multiple locations and are most consistent with the spread of the virus from bobcats to pumas. Although the ultimate causes remain unknown, these transmission events may occur as a result of puma predation on bobcats, a situation similar to that which fostered transmission of HIV to humans, and likely represent the emergence of a lentivirus with relaxed barriers to cross-species transmission. This unusual observation provides a valuable opportunity to evaluate the ecological, behavioral, and molecular conditions that favor repeated transmissions and persistence of lentivirus between species.

T-lymphocyte profiles in FIV-infected wild lions and pumas reveal CD4 depletion.

Feline immunodeficiency virus (FIV) is a lentivirus related to human immunodeficiency virus (HIV) that causes feline AIDS in the domestic cat (Felis catus). Serological surveys indicate that at least 25 other species of cat possess antibodies that cross-react with domestic cat FIV. Most infected nondomestic cat species are without major symptoms of disease. Long-term studies of FIV genome variation and pathogenesis reveal patterns consistent with coadaptation of virus and host in free-ranging FIV-Ple-infected African lions (Panthera leo) and FIV-Pco-infected pumas (Puma concolor) populations. This report examined correlates of immunodeficiency in wild and captive lions and pumas by quantifying CD5(+), CD4(+), and CD8(+) T-cell subsets. Free-ranging FIV-Ple-infected lions had immunofluorescence flow cytometry (IFC) profiles marked by a dramatic decline in CD4(+) subsets, a reduction of the CD4(+)/CD8(+) ratio, reduction of CD8(+)beta(high) cells, and expansion of the CD8(+)beta(low) subset relative to uninfected lions. An overall significant depletion in CD5(+) T-cells in seropositive lions was linked with a compensatory increase in total CD5(-) lymphocytes. The IFC profiles were altered significantly in 50% of the seropositive individuals examined. The FIV-Pco-infected pumas had a more generalized response of lymphopenia expressed as a significant decline in total lymphocytes, CD5(+) T-cells, and CD5(-) lymphocytes as well as a significant reduction in CD4(+) T-cells. Like lions, seropositive pumas had a significant decline in CD8(+)beta(high) cells but differed by not having compensatory expansion of CD8(+)beta(low) cells relative to controls. Results from FIV-infected lions and pumas parallel human and Asian monkey CD4(+) diminution in HIV and SIV infection, respectively, and suggest there may be unrecognized immunological consequences of FIV infection in these two species of large cats.

Second-generation integrated genetic linkage/radiation hybrid maps of the domestic cat (Felis catus).

We report construction of second-generation integrated genetic linkage and radiation hybrid (RH) maps in the domestic cat (Felis catus) that exhibit a high level of marker concordance and provide near-full genome coverage. A total of 864 markers, including 585 coding loci (type I markers) and 279 polymorphic microsatellite loci (type II markers), are now mapped in the cat genome. We generated the genetic linkage map utilizing a multigeneration interspecies backcross pedigree between the domestic cat and the Asian leopard cat (Prionailurus bengalensis). Eighty-one type I markers were integrated with 247 type II markers from a first-generation map to generate a map of 328 loci (320 autosomal and 8 X-linked) distributed in 47 linkage groups, with an average intermarker spacing of 8 cM. Genome coverage spans approximately 2,650 cM, allowing an estimate for the genetic length of the sex-averaged map as 3,300 cM. The 834-locus second-generation domestic cat RH map was generated from the incorporation of 579 type I and 255 type II loci. Type I markers were added using targeted selection to cover either genomic regions underrepresented in the first-generation map or to refine breakpoints in human/feline synteny. The integrated linkage and RH maps reveal approximately 110 conserved segments ordered between the human and feline genomes, and provide extensive anchored reference marker homologues that connect to the more gene dense human and mouse sequence maps, suitable for positional cloning applications.

Ixodid ticks from panthers and bobcats in Florida.

Ixodid ticks were present in all 189 samples examined from 53 Florida panthers (Felis concolor coryi, 104 collections) and 85 bobcats (Felis rufus floridana) in Florida (USA) between 1974 and 1991. We identified 3,251 ticks from panthers and 918 from bobcats. Specimens of Dermacentor variabilis, Ixodes scapularis, I. affinis, Amblyomma maculatum, and A. americanum were present on 49, 39, 17, seven, and two of the 53 Florida panthers, respectively, and comprised 36%, 55%, 7%, 1%, and < 1% of the 3,251 ticks collected from panthers. Ixodes scapularis, D. variabilis, and I. affinis were present on 61, 56, and 11 of the 85 bobcats respectively, and comprised 58%, 39%, and 2% of the 919 ticks collected. Amblyomma americanum and A. maculatum were found infrequently and comprised < 1% of the total ticks collected from bobcats. Only adult ticks were found on the cats, except for one D. variabilis nymph and three A. americanum nymphs that were found on bobcats.

Gonadotrophin dose and timing of anaesthesia for laparoscopic artificial insemination in the puma (Felis concolor).

Ovarian response to equine chorionic gonadotrophin (eCG) and human chorionic gonadotrophin (hCG), the effect of timing of anaesthesia relative to hCG injection and the use of laparoscopic intrauterine artificial insemination were examined in the puma (Felis concolor). In Expt 1, females were treated with 100 (n = 6) or 200 (n = 8) IU eCG (i.m.) followed 80 h later by 100 IU hCG (i.m.) and were then anaesthetized 40-43 h after hCG injection for ovarian assessment. Although there was no difference (P > 0.05) in the number of unovulated ovarian follicles, females treated with 200 IU eCG had more (P < 0.05) corpora lutea per female and more corpora lutea as a percentage of the total number of ovarian structures. In Expt 2, all females were treated with 200 IU eCG and 80 h later with 100 IU hCG, and then anaesthetized either 31-39 h (Group A; n = 8) or 41-50 h (Group B; n = 6) after hCG injection for ovarian assessment. All Group B pumas ovulated compared with only three (37.5%) Group A females (P < 0.05). Compared with Group A, Group B pumas had more corpora lutea per female, more corpora lutea as a percentage of the total number of ovarian structures, and fewer unovulated follicles (P < 0.05). One of nine post-ovulatory females laparoscopically inseminated in utero with 16 x 10(6) motile spermatozoa became pregnant and delivered a healthy cub.(ABSTRACT TRUNCATED AT 250 WORDS)

The consequences of demographic reduction and genetic depletion in the endangered Florida panther.

The Florida panther has recently suffered severe range and demographic contraction, leaving a remarkably low level of genetic diversity. This exerts a severe fitness cost, manifested by spermatozoal defects, cryptorchidism, cardiac abnormalities and infectious diseases that threaten the survival of the subspecies.

Seroprevalence of infectious disease agents in free-ranging Florida panthers (Felis concolor coryi).

Serum samples obtained from 38 free-ranging Florida panthers (Felis concolor coryi) in southern Florida, March 1978 through February 1991, were tested for antibodies against eight bacterial, parasitic, and viral disease agents. Sera were positive for antibodies against feline panleukopenia virus (FPV) (78%), feline calicivirus (56%), feline immunodeficiency virus/puma lentivirus (37%), feline enteric coronavirus/feline infectious peritonitis virus (19%), and Toxoplasma gondii (9%). All samples were seronegative for Brucella spp., feline rhinotracheitis virus, and pseudorabies virus. In addition, all the animals tested were negative for feline leukemia virus p27 antigen as determined by enzyme-linked immunosorbent assay. Feline panleukopenia virus was considered to be a potentially significant disease agent; FPV antibodies occurred in the highest prevalences in older age classes (P = 0.027) and in panthers living in the dense mixed hardwood swamps in the western portion of their range compared to the open cypress and sawgrass prairies to the east (P = 0.096). Because < 50 animals remain in this relict population and the probable resultant depression of genetic diversity and lowered disease resistance, FPV or other disease agents could contribute to the extinction of this endangered subspecies.

Morphology, prevalence, and distribution of Sarcocystis spp. in white-tailed deer (Odocoileus virginianus) from Florida.

Three morphologically distinct types of sarcocysts (I, II, and III) were identified by light microscopy in tongues from 403 white-tailed deer (Odocoileus virginianus) collected in Florida (USA) over a 7-yr-period. Based on electron microscopy of representative examples of these sarcocysts, there were four distinctive wall structures. We concluded that one of these (Type I) was representative of Sarcocystis odocoileocanis and another (Type III) was representative of an unnamed species previously described from white-tailed deer in Montana. Type II could be divided further into two forms (IIA and IIB) that may represent two underscribed species or developmental stages of the same species. Sarcocystis odoi, another previously recognized sarcosporidian from white-tailed deer, was not found. Sarcocysts of Types I and II were distributed nonrandomly in tongue muscle, being more common in the basal portion, whereas Type III was distributed randomly throughout the tongue. Single infections (one of the three types) accounted for 63% of the infected deer, while double infections occurred in 28% and triple infections in 4%. Types I and II were found in deer throughout the state, but Type III occurred only in deer from southern Florida. In 1988 and 89, the statewide prevalences for Types I, II, and III were 57, 20, and 6%, respectively. Prevalences of Type I ranged from 94% in the panhandle region (northern Florida) to 34% in the southern part of the state. Prevalences of all three types increased with age.

Worldwide prevalence of lentivirus infection in wild feline species: epidemiologic and phylogenetic aspects.

The natural occurrence of lentiviruses closely related to feline immunodeficiency virus (FIV) in nondomestic felid species is shown here to be worldwide. Cross-reactive antibodies to FIV were common in several free-ranging populations of large cats, including East African lions and cheetahs of the Serengeti ecosystem and in puma (also called cougar or mountain lion) populations throughout North America. Infectious puma lentivirus (PLV) was isolated from several Florida panthers, a severely endangered relict puma subspecies inhabiting the Big Cypress Swamp and Everglades ecosystems in southern Florida. Phylogenetic analysis of PLV genomic sequences from disparate geographic isolates revealed appreciable divergence from domestic cat FIV sequences as well as between PLV sequences found in different North American locales. The level of sequence divergence between PLV and FIV was greater than the level of divergence between human and certain simian immunodeficiency viruses, suggesting that the transmission of FIV between feline species is infrequent and parallels in time the emergence of HIV from simian ancestors.

Sarcocysts in the Florida bobcat (Felis rufus floridanus).

Sarcocysts were found in the tongue, diaphragm, heart, intestinal tunica muscularis, and skeletal muscle of bobcats (Felis rufus floridanus) collected in Florida (USA). The tongue was found to be the best indicator tissue for sarcocysts (P less than 0.005). Thirty of 60 bobcats screened were found to contain sarcocysts in at least one of the muscle tissues examined. Of the positive bobcats, 28 of 28 tongues contained sarcocysts, while only 10 of 27 (37%), and 8 of 26 (31%) contained sarcocysts in the diaphragm or cardiac muscle, respectively. Although immune suppression has been suggested as a possible reason for formation of sarcocysts in some carnivores, no such correlation was evident in the bobcats. Comparisons of prey species taken by the panther and bobcat, and overlap of geographical range by the two species leave questions as to the source of infection, and the species of Sarcocystis that is infecting both felids.

Iatrogenic transmission of Cytauxzoon felis from a Florida panther (Felix concolor coryi) to a domestic cat.

A laboratory cat died 12 days after intraperitoneal inoculation of a 1 ml suspension containing 1.5 x 10(6) blood mononuclear cells from a Florida panther (Felis concolor coryi). Gross, histologic and ultrastructural investigations revealed the cause of death to be infection by Cytauxzoon felis, a protozoal parasite known to cause a rapidly fatal disease (cytauxzoonosis) in domestic cats. The bobcat (Felis rufus) has been identified as a natural host for C. felis. This report implicates the Florida panther as another possible host for C. felis.

Prevalence and implications of feline coronavirus infections of captive and free-ranging cheetahs (Acinonyx jubatus).

The extent and progression of exposure to feline infectious peritonitis (FIP) virus in the cheetah, Acinonyx jubatus, was monitored by a world-wide serological survey with indirect fluorescent antibody titers to coronavirus. The indirect fluorescent antibody assay was validated by Western blots, which showed that all indirect fluorescent antibody-positive cheetah sera detected both domestic cat and cheetah coronavirus structural proteins. There was a poor correlation between indirect fluorescent antibody results and the presence of coronaviruslike particles in cheetah feces, suggesting that electron microscopic detection of shed particles may not be an easily interpreted diagnostic parameter for FIP disease. Low, but verifiable (by Western blots [immunoblots]) antibody titers against coronavirus were detected in eight free-ranging cheetahs from east Africa as well as from captive cheetahs throughout the world. Of 20 North American cheetah facilities screened, 9 had cheetahs with measurable antibodies to feline coronavirus. Five facilities showed patterns of an ongoing epizootic. Retrospective FIP virus titers of an FIP outbreak in a cheetah-breeding facility in Oregon were monitored over a 5-year period and are interpreted here in terms of clinical disease progression. During that outbreak the morbidity was over 90% and the mortality was 60%, far greater than any previously reported epizootic of FIP in any cat species. Age of infection was a significant risk factor in this epizootic, with infants (less than 3 months old) displaying significantly higher risk for mortality than subadults or adults. Based upon these observations, empirical generalizations are drawn which address epidemiologic concerns for cheetahs in the context of this lethal infectious agent.

Oocyte recovery, maturation and fertilization in vitro in the puma (Felis concolor).

Eight female pumas were treated i.m. with 1000 (N = 5) or 2000 (N = 3) i.u. PMSG followed 84 h later by 800 i.u. hCG. Eggs were recovered 24-26 h after hCG from ovarian follicles by using laparoscopy and transabdominal aspiration. Mature eggs were inseminated in vitro 4-6 h later whereas immature eggs were cultured for 24 h and then inseminated. Electroejaculates from 3 pumas were diluted with mKRB before insemination to evaluate the influence of sperm concentration on fertilization. Seven of 8 pumas responded with follicle development, and 140 eggs were recovered from 145 follicles (96.6%; 77 mature, 43 immature, 20 degenerate eggs; mean +/- s.e.m., 20.0 +/- 5.9 eggs/female). Overall fertilization rate was 43.5% (total eggs fertilized = 40) despite using inseminates containing 82-99% pleiomorphic spermatozoa. Of the 36 immature oocytes matured in vitro and inseminated, 12 were fertilized even though 50% of the inseminating spermatozoa contained an acrosomal defect. Fertilization rate of mature oocytes collected from follicles appeared unrelated (P greater than 0.05) to PMSG dose or number of spermatozoa/inseminate. This study demonstrates that a high proportion of follicular eggs can be recovered laparoscopically from adult pumas treated with PMSG and hCG. These gametes are capable of being fertilized in vitro (immediately or after maturation in vitro) even with low quality semen with a high incidence of sperm pleiomorphisms.

Sarcocystis sp. in muscles of free-ranging Florida panthers and cougars (Felis concolor).

Sarcocysts of Sarcocystis sp. were found in the striated muscles from 11 of 14 wild Florida panthers (Felis concolor coryi) and four of four cougars (two wild F. concolor stanleyana and two captive F. concolor of undetermined subspecies). The common occurrence of sarcocysts in muscles of top carnivores such panthers and cougars is unexplained. This stage of the life cycle is normally confined to the muscles of the prey species. Because large felids are rarely preyed upon, it is unlikely that a species of Sarcocystis has evolved using large cats as intermediate hosts. Therefore, the presence of these sarcocysts might be an indication of immune compromise in these felids, enabling the atypical development of the sarcocysts.

Biological and pathological consequences of feline infectious peritonitis virus infection in the cheetah.

An epizootic of feline infectious peritonitis in a captive cheetah population during 1982-1983 served to focus attention on the susceptibility of the cheetah (Acinoyx jubatus) to infectious disease. Subsequent observations based upon seroepidemiological surveys and electron microscopy of fecal material verified that cheetahs were indeed capable of being infected by coronaviruses, which were antigenically related to coronaviruses affecting domestic cats, i.e. feline infectious peritonitis virus/feline enteric coronavirus. Coincident with the apparent increased susceptibility of the cheetah to infectious diseases, were observations that the cheetah was genetically unusual insofar as large amounts of enzyme-encoding loci were monomorphic, and that unrelated cheetahs were capable of accepting allogenic skin grafts. These data provided the basis for a hypothesis that the cheetah, through intensive inbreeding, had become more susceptible to viral infections as a result of genetic homogeneity.

Similarity in ejaculate-endocrine characteristics in captive versus free-ranging cheetahs of two subspecies.

Ejaculate-endocrine characteristics were measured in 23 captive cheetahs (Acinonyx jubatus jubatus) in North American zoos and in 8 free-ranging cheetahs (A.j. raineyi) in eastern Africa (Tanzania). A standardized electroejaculation protocol was used, and numbers of motile spermatozoa were similar (p greater than 0.05) between groups. Of the spermatozoa collected by electroejaculation, 70.6 +/- 3.3% and 75.9 +/- 4.4% were morphologically abnormal in the captive "North American" and in the free-ranging, eastern African populations, respectively. Adrenal activity, as measured by an acute, temporal rise and fall in serum cortisol levels during and after electroejaculation, was no different (p greater than 0.05) between groups. Although serum luteinizing hormone (LH) levels were less (p less than 0.05) in the free-ranging than in the captive animals, serum testosterone concentrations were similar. The data indicate that the comparatively poor reproductive performance of cheetahs maintained in zoological parks is not attributable to a captivity-induced response afflicting the male. Furthermore, there is no evidence that ejaculate/endocrine characteristics differ between the two subspecies. Because adrenal/gonadal activity and the number of pleiomorphic spermatozoa are similar between the test groups, the results suggest that spermatozoal diversity originates as a result of the extreme genetic monomorphism observed universally in the species.

Genetic basis for species vulnerability in the cheetah.

A population genetic survey of over 200 structural loci previously revealed that the South African cheetah (Acinonyx jubatus jubatus) has an extreme paucity of genetic variability, probably as a consequence of a severe population bottleneck in its recent past. The genetic monomorphism of the species is here extended to the major histocompatibility complex, since 14 reciprocal skin grafts between unrelated cheetahs were accepted. The apparent consequences of such genetic uniformity to the species include (i) great difficulty in captive breeding, (ii) a high degree of juvenile mortality in captivity and in the wild, and (iii) a high frequency of spermatozoal abnormalities in ejaculates. The species vulnerability of the cheetah was demonstrated by an epizootic of coronavirus-associated feline infectious peritonitis in an Oregon breeding colony in 1983. Exposure and spread of the coronavirus, which has a very low morbidity in domestic cats (approximately 1 percent), has decimated a heretofore productive and healthy captive population. The extreme genetic monomorphism, especially at the major histocompatibility complex, and the apparent hypersensitivity of the cheetah to a viral pathogen may be related, and provide a biological basis for understanding the adaptive significance of abundant genetic variation in outbred mammalian species.