The Role of Domoic Acid in Abortion and Premature Parturition of California Sea Lions (Zalophus Californianus) on San Miguel Island, California

Goldstein, Tracey; Zabka, Tanja S.; DeLong, Robert L.; Wheeler, Elizabeth; Ylitalo, Gina M.; Bargu, Sibel; Silver, Mary W.; Leighfield, Tod A.; Dolah, Frances Van; Langlois, Gregg W.; Sidor, Inga; Dunn, J. Lawrence; Gulland, Frances M. D.

doi:10.7589/0090-3558-45.1.91

Cited by 68 publications

(64 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Prior investigation of aborted and premature Californian sea lions Zalophus californianus showed the presence of Brucella spp. DNA in 3 out of 59 placentae, and 2 of the placentae were also culture positive, but had no Brucella-associated histopathology (Goldstein et al 2009). Abortions are also commonly observed in Australian fur seals Arcto cephalus pusillus, and a high prevalence of Brucella-seropositive adult females (57%) has been detected (Lynch et al 2011a), while the seroprevalence among pups was close to 0%.…”

Section: Discussionmentioning

confidence: 99%

Age-dependent prevalence of anti-Brucella antibodies in hooded seals Cystophora cristata

et al. 2013

View full text Add to dashboard Cite

Investigations of hooded seals Cystophora cristata have revealed high prevalences of Brucella-positive seals in the reduced Northeast Atlantic stock, compared to the increasing Northwest Atlantic stock. This study evaluated the relation between Brucella-serostatus in seals in the Northeast Atlantic stock and age, sex, body condition and reproduction. Bacteriology documented which animals and organs were B. pinnipedialis positive. No relationship was observed between Brucella-serostatus and body condition or reproductive traits. Pups (<1 mo old) had a substantially lower probability of being seropositive (4/159, 2.5%) than yearlings (6/17, 35.3%), suggesting that exposure may occur post-weaning, during the first year of life. For seals >1 yr old, the mean probability of being seropositive decreased with age, with no seropositives older than 5 yr, indicating loss of antibody titre with either chronicity or clearance of infection. The latter explanation seems to be most likely as B. pinnipedialis has never been isolated from a hooded seal >18 mo old, which is consistent with findings in this study; B. pinnipedialis was isolated from the retropharyngeal lymph node in 1 seropositive yearling (1/21, 5%). We hypothesize that this serological and bacteriological pattern is due to environmental exposure to B. pinnipedialis early in life, with a subsequent clearance of infection. This raises the question of a reservoir of B. pinnipedialis in the hooded seal food web.KEY WORDS: Pinniped · Pups · Brucellosis · Serostatus · Bacteriology · Infection clearance · Atlantic hooded seal stock · Food web Resale or republication not permitted without written consent of the publisherDis Aquat Org 106: [187][188][189][190][191][192][193][194][195][196] 2013 Greenland (NWS) (Andersen et al. 2009) and the Nordic Seas (Greenland, Norwegian and Icelandic Seas, NES) (Folkow et al. 1996(Folkow et al. , 2010.While estimates of abundance in the NWS have increased since the 1980s (Hammill & Stenson 2006), abundance of the NES appears to have decreased to only 10 to 15% of the 1946 population size, from 575 000 hooded seals in 1946 to approximately 85 000 hooded seals in 2011, and has remained stable at this low level since the 1980s (ICES 2011). Hooded seal hunts in the West Ice have been conducted since the 18th century, and after 1920 the hunt was of a significant extent. In 1958, agreements were made between Norway and the Soviet Union on time and activity restrictions on the hooded seal hunt in the West Ice, but it was not until 1971 that quotas were introduced (Bjørge 2010). The introduction of quotas did not alter the negative population development in the NES, and due to the decline of the NES, no commercial hunt has been conducted on the NES since 2007 (ICES 2011), and the hooded seal species has been classified since 2008 as 'Vulnerable' in the Red List of Threatened Species of the International Union for Conservation of Nature (IUCN) (Kovacs 2008).Brucella spp. were first isolated from marine mammals in 1994 (Ross et al....

show abstract

Section: Discussionmentioning

confidence: 99%

Age-dependent prevalence of anti-Brucella antibodies in hooded seals Cystophora cristata

et al. 2013

View full text Add to dashboard Cite

show abstract

“…infections in pinnipeds appear to be most commonly associated with bronchopneumonia, potentially only acting as a secondary agent after parasitic infection (Prenger-Berninghoff et al, 2008). However, Brucella was recently suggested as a possible cause of abortion in California sea lions (Zalophus californianus; Goldstein et al, 2009).…”

Section: Introductionmentioning

confidence: 99%

Epizootiology of Brucella Infection in Australian Fur Seals

Lynch

Duignan

Taylor

et al. 2011

Journal of Wildlife Diseases

View full text Add to dashboard Cite

ABSTRACT:Novel members of the bacterial genus Brucella have recently emerged as pathogens of various marine mammal species and as potential zoonotic agents. We investigated the epizootiology of Brucella infection in Australian fur seals (Arctocephalus pusillus doriferus) by establishing demographic and temporal variations in antibody prevalence, attempting isolation of the causative agent, and determining whether this potential pathogen is involved in frequent abortions observed in this pinniped species. Two competitive enzyme-linked immunosorbent assays (cELISAs), an indirect ELISA, and a fluorescence polarization assay (FPA) were used to test sera for Brucella antibodies. The FPA and cELISA proved suitable for use in this species. Significant differences in antibody prevalence were found between age classes of seals sampled between 2007 and 2009 at one colony. Pups sampled at this site (n5134) were negative for Brucella antibodies by all serologic tests but 17 of 45 (38%) of juveniles were antibody-positive. Antibody prevalence in adult females was significantly higher than in juveniles (P50.044). . Inflammatory lesions suggestive of infectious agents were found in 14 of 39 aborted Australian fur seal pups, but pathologic changes were not uniformly consistent for Brucella infection. Culture and PCR investigations on fetal tissues were negative for Brucella. Culture and PCR on selected fresh or frozen tissues from 36 juvenile and adult animals were also negative. We suspect that the prevalence of active infection with Brucella in Australian fur seals is low relative to antibody prevalence.

show abstract

“…14 Multiple etiologies have been suggested for this scenario, including interrelationships between disease agents and environmental contaminants, 14 ingestion of toxic algae and bacterial infections. 15,28 In the Cape fur seal (A. p. pusillus), a gestational failure rate of 21% was measured between 1988 and 1991 but the relative contributions of failure of embryonic implantation and late-term spontaneous abortions to this figure were not established. 16 In both Cape and Australian fur seals, nutritional factors probably influence annual variations in abortion rates as fewer pups are produced in years when females have a lower mean body condition index.…”

Section: Discussionmentioning

confidence: 99%

Mycoplasmas in Australian fur seals (Arctocephalus pusillus doriferus): identification and association with abortion

et al. 2011

View full text Add to dashboard Cite

Abstract. Bacteria from the genus Mycoplasma are common inhabitants of the respiratory, gastrointestinal, and genital tracts of mammals. The understanding of the pathological significance of mycoplasmas in seals is poor, as few studies have utilized the specific culture techniques required to isolate these bacteria. The current study surveyed for the Mycoplasma species present in Australian fur seals (Arctocephalus pusillus doriferus) and investigated the association between infection and pathology. Mycoplasmas were found in the nasal cavities of 55/80 (69%) of apparently healthy individuals. Isolates from 18 individuals were investigated through 16S ribosomal RNA sequencing, and 3 species were identified: M. zalophi, M. phocae, and Mycoplasma sp. (GenBank no. EU714238.1), all of which had previously been isolated from Northern Hemisphere pinnipeds. In addition, mycoplasmas were isolated from the lungs of 4 out of 16 juveniles and 1 out of 5 adults sampled at necropsy. Isolates obtained were M. zalophi, Mycoplasma sp. EU714238.1, and M. phocicerebrale, but infection was not associated with lung pathology in these age classes. Inflammatory disease processes of the heart and/or lungs were present in 12 out of 32 (38%) aborted fetuses on microscopic examination. Predominant findings were interstitial pneumonia, pericarditis, and myocarditis. Mycoplasma phocicerebrale was isolated from the thymus of an aborted fetus, and 3 out of 11 (27%) fetuses with inflammatory heart or lung lesions were PCR-positive for Mycoplasma. In conclusion, several species of Mycoplasma are part of the normal flora of the nasal cavity of Australian fur seals, and some mycoplasmas may be associated with abortion in this species of seal.

show abstract

The Role of Domoic Acid in Abortion and Premature Parturition of California Sea Lions (Zalophus Californianus) on San Miguel Island, California

Cited by 68 publications

References 49 publications

Age-dependent prevalence of anti-Brucella antibodies in hooded seals Cystophora cristata

Age-dependent prevalence of anti-Brucella antibodies in hooded seals Cystophora cristata

Epizootiology of Brucella Infection in Australian Fur Seals

Mycoplasmas in Australian fur seals (Arctocephalus pusillus doriferus): identification and association with abortion

Contact Info

Product

Resources

About