Fatal marine
Brucella
infections with histologic lesions specific to the central nervous system (CNS), known as neurobrucellosis, have been described in 5 species of odontocete cetaceans in the UK: ...striped dolphins
Stenella coeruleoalba
, Atlantic white-sided dolphins
Lagenorhynchus acutus
, short-beaked common dolphins
Delphinus delphis
, long-finned pilot whale
Globicephala melas
and Sowerby’s beaked whale
Mesoplodon bidens
. To date, these CNS lesions have only been associated with
Brucella ceti
ST26 and not with
B. pinnipedialis
, which is rarely isolated from cetaceans and, although commonly found in various seal species, has never been associated with any pathology. This paper describes the first report of neurobrucellosis in a common minke whale
Balaenoptera acutorostrata
which was associated with the isolation of
Brucella pinnipedialis
ST24 and co-infection with
Balaenoptera acutorostrata
gamma-herpesvirus 2. This is the first report of neurobrucellosis in any species of mysticete and the first report of
Brucella pinnipedialis
in association with any pathology in any species of marine mammal, which may be due to co-infection with a herpesvirus, as these are known to be associated with immunosuppression.
Brucella ceti
has been recovered from a number species of cetaceans worldwide over the last 25 yr. Here we report, for the first time, the recovery of
B. ceti
from a Risso’s dolphin
Grampus griseus
...and a killer whale
Orcinus orca
. Recovery from an abdominal mass in the dolphin provides further evidence of the systemic pathogenic potential for
B. ceti
infection in cetaceans. The isolation of
B. ceti
ST23 (porpoise cluster) from a killer whale from a group known to eat other marine mammals raises the possibility of infection via ingestion. This report takes the number of cetacean species in UK coastal waters from which
B. ceti
has been isolated to 11 and highlights the value of routine, comprehensive and specific screening for significant pathogens such as
Brucella
sp. by strandings networks.
Since 2000 there has been a major decline in the abundance of Scottish harbour seals Phoca vitulina. The causes of the decline remain uncertain. The aim of this study was to establish the extent to ...which the seals in the regions of greatest decline have been exposed to Brucella, a bacterial pathogen that causes reproductive failure in terrestrial mammalian hosts. Tissues from dead seals collected between 1992 and 2013 were cultured for Brucella (n = 150). Serum samples collected from live capture-released seals (n = 343) between 1997 and 2012 were tested for Brucella antibodies using the Rose Bengal plate agglutination test (RBT) and a competitive enzyme-linked immunosorbent assay (cELISA). In total, 16% of seals cultured had Brucella isolated from one or more tissues, but there were no pathological signs of infection. The cELISA results were more sensitive than the RBT results, showing that overall 25.4% of seals were seropositive, with the highest seroprevalence in juveniles. As there was no evidence of either a higher seroprevalence or higher circulating antibody levels in seropositive animals in the areas with the greatest declines, it was concluded that Brucella infection is likely not a major contributing factor to recent declines. However, the consistently high proportion of seals exposed to Brucella indicates possible endemicity in these populations, likely due to B. pinnipedialis, which has demonstrated a preference for pinniped hosts. Importantly, given the close proximity between seals, humans and livestock in many areas, there is the potential for cross-species infections.
Brucella species infecting marine mammals was first reported in 1994 and in the years since has been documented in various species of pinnipeds and cetaceans. While these reports have included ...species that inhabit Arctic waters, the few available studies on bearded seals Erignathus barbatus have failed to detect Brucella infection to date. We report the first isolation of Brucella pinnipedialis from a bearded seal. The isolate was recovered from the mesenteric lymph node of a bearded seal that stranded in Scotland and typed as ST24, a sequence type associated typically with pinnipeds. Furthermore, serological studies of free-ranging bearded seals in their native waters detected antibodies to Brucella in seals from the Chukchi Sea (1990-2011; 19%) and Svalbard (1995-2007; 8%), whereas no antibodies were detected in bearded seals from the Bering Sea or Bering Strait or from captive bearded seals.
Fatal Brucella ceti infection with histological lesions specific to the central nervous system has been described in only 3 species of cetaceans: striped dolphins Stenella coeruleoalba, Atlantic ...white-sided dolphins Lagenorhynchus acutus and short-beaked common dolphins Delphinus delphis. This paper describes the first report of a B. ceti-associated meningoencephalitis in a long-finned pilot whale Globicephala melas, showing the increasing range of species susceptibility. Brucella was recovered in larger numbers from cerebrospinal fluid than from brain tissue and is the sample of choice for isolation.
The fluorescence polarisation assay (FPA) is a recently described test for the serological diagnosis of
Brucella infection. It has many methodological advantages over older, more established tests ...and can be performed in a fraction of the time. To validate the FPA, serum samples from 146 confirmed (by culture)
Brucella-infected cattle were tested in conjunction with serum samples from 1947 noninfected cattle. The competitive ELISA (cELISA) was validated using these positive reference samples and 1440 negative samples, while data for the indirect ELISA (iELISA) was generated from 6957 negative samples plus the positive sera. Published diagnostic specificity (DSp) data for the complement fixation test (CFT) and serum agglutination test (SAT) was used in conjunction with the test results on the positive sera to obtain diagnostic specificity plus diagnostic sensitivity (DSn). After selection of a cutoff for the FPA and cELISA, the diagnostic specificity and sensitivity total for each test were compared. The results, with 95% confidence intervals, were: FPA (195.7±2.79), iELISA (195.0±2.70), cELISA (194.9±3.48), CFT (191.7±4.45), and SAT (180.4±6.33). The data presented supports the use of the FPA in diagnosis of brucellosis and questions the use of the SAT and CFT for either screening or confirmatory testing.
Aims: To select an anti-fungal agent to replace cycloheximide in the media used for isolation of Brucella. Methods and Results: One potential agent, natamycin, was evaluated using 28 Brucella ...isolates, 18 yeasts and 14 fungi. The material for the evaluation included 37 bovine milk samples, six bovine vaginal swabs and 45 milk samples artificially infected with Brucella. The recovery of Brucella only from the artificially-inoculated milk samples increased with the use of the medium containing natamycin instead of cycloheximide, at the same time significantly inhibiting the growth of yeasts, fungi and other bacteria. The inclusion of either anti-fungal agent allowed growth of the 28 Brucella isolates and totally prevented the growth of all 18 yeasts and 13 of the 14 fungi. Conclusions: Based on the results it was concluded that natamycin would be a suitable alternative to cycloheximide. Significance and Impact of the Study: Cycloheximide has become unavailable worldwide and is currently an anti-fungal constituent of the medium often used for isolation of Brucella organisms. The use of natamycin as a replacement in the formulation did not inhibit growth of Brucella and was effective at eliminating most contaminants.
Brucella canis in South Africa Gous, T. A.; Janse van Rensburg, W. J.; Gray, M. ...
Veterinary record,
11/2005, Letnik:
157, Številka:
21
Journal Article
Recenzirano
The first case originated from the Society for the Prevention of Cruelty to Animals ( SPCA ) in Cape Town and the second was a stray from Knysna.
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