Exposure of bighorn sheep to domestic goats colonized with Mycoplasma ovipneumoniae induces sub-lethal pneumonia.

Background: Bronchopneumonia is a population limiting disease of bighorn sheep (Ovis canadensis) that has been associated with contact with domestic Caprinae. The disease is polymicrobial but is initiated by Mycoplasma ovipneumoniae, which is commonly carried by both domestic sheep (O. aries) and goats (Capra aegagrus hircus).

Role of carriers in the transmission of pneumonia in bighorn sheep (Ovis canadensis).

In the absence of livestock contact, recurring lamb mortality in bighorn sheep (Ovis canadensis) populations previously exposed to pneumonia indicates the likely presence of carriers of pneumonia-causing pathogens, and possibly inadequate maternally derived immunity. To investigate this problem we commingled naïve, pregnant ewes (n=3) with previously exposed rams (n=2). Post-commingling, all ewes and lambs born to them acquired pneumonia-causing pathogens (leukotoxin-producing Pasteurellaceae and Mycoplasma ovipneumoniae), with subsequent lamb mortality between 4-9 weeks of age.

Serologic, trace element, and fecal parasite survey of free-ranging, female mule deer (Odocoileus hemionus) in eastern Washington, USA.

Blood and fecal samples collected from 97 free-ranging mule deer (Odocoileus hemionus), from four distinct herds during the spring of 2000 or 2001 in eastern Washington, US, were tested for exposure to selected pathogens, concentrations of trace elements, and presence of parasites in feces. Antibodies were detected to the following: Leptospira interrogans serovar Bratislava (4%), Leptospira interrogans serovar Canicola (1%), Leptospira interrogans serovar Grippotyphosa (13%), Bovine viral diarrhea virus 1 (57%), Bovine respiratory syncytial virus (71%), Infectious bovine rhinotracheitis virus (51%), Bovine parainfluenza virus 3 (61%), Bluetongue virus (25%), and Epizootic hemorrhagic disease virus (25%); 3 of 63 (5%) samples had antibody to Neospora spp. All samples tested for antibody to Brucella abortus and L.

Epizootic pneumonia of bighorn sheep following experimental exposure to Mycoplasma ovipneumoniae.

Background: Bronchopneumonia is a population limiting disease of bighorn sheep (Ovis canadensis). The cause of this disease has been a subject of debate. Leukotoxin expressing Mannheimia haemolytica and Bibersteinia trehalosi produce acute pneumonia after experimental challenge but are infrequently isolated from animals in natural outbreaks.

Role of Bibersteinia trehalosi, respiratory syncytial virus, and parainfluenza-3 virus in bighorn sheep pneumonia.

Pneumonic bighorn sheep (BHS) have been found to be culture- and/or sero-positive for Bibersteinia trehalosi, respiratory syncytial virus (RSV), and parainfluenza-3 virus (PI-3). The objective of this study was to determine whether these pathogens can cause fatal pneumonia in BHS. In the first study, two groups of four BHS each were intra-tracheally administered with leukotoxin-positive (Group I) or leukotoxin-negative (Group II) B.

Survival of bighorn sheep (Ovis canadensis) commingled with domestic sheep (Ovis aries) in the absence of Mycoplasma ovipneumoniae.

To test the hypothesis that Mycoplasma ovipneumoniae is an important agent of the bighorn sheep (Ovis canadensis) pneumonia that has previously inevitably followed experimental commingling with domestic sheep (Ovis aries), we commingled M. ovipneumoniae-free domestic and bighorn sheep (n=4 each). One bighorn sheep died with acute pneumonia 90 days after commingling, but the other three remained healthy for >100 days.

A multivalent Mannheimia-Bibersteinia vaccine protects bighorn sheep against Mannheimia haemolytica challenge.

Bighorn sheep (BHS) are more susceptible than domestic sheep (DS) to Mannheimia haemolytica pneumonia. Although both species carry M. haemolytica as a commensal bacterium in the nasopharynx, DS carry mostly leukotoxin (Lkt)-positive strains while BHS carry Lkt-negative strains.

Defective bacterial clearance is responsible for the enhanced lung pathology characteristic of Mannheimia haemolytica pneumonia in bighorn sheep.

The molecular and cellular basis for the enhanced lung pathology and mortality caused by Mannheimia haemolytica in bighorn sheep (BHS, Ovis canadenesis), in comparison to domestic sheep (DS, Ovis aries), is not clear. Polymorphonuclear leukocytes (PMNs) of BHS are four- to eight-fold more susceptible to M. haemolytica leukotoxin-induced cytolysis, which is likely to reduce the number of functional phagocytes in the lung.

Co-expression of ovine LPS receptor CD14 with Mannheimia haemolytica leukotoxin receptor LFA-1 or Mac-1 does not enhance leukotoxin-induced cytotoxicity.

Leukotoxin (Lkt) and LPS are the major virulence determinants of Mannheimia haemolytica that contribute to the pathogenesis of bovine and ovine pneumonic pasteurellosis. We have previously identified bovine and ovine CD18 as the functional receptor for Lkt. LPS complexes with Lkt resulting in increased thermal stability and enhanced cytotoxic activity of Lkt.

Transmission of Mannheimia haemolytica from domestic sheep (Ovis aries) to bighorn sheep (Ovis canadensis): unequivocal demonstration with green fluorescent protein-tagged organisms.

Previous studies demonstrated that bighorn sheep (Ovis canadensis) died of pneumonia when commingled with domestic sheep (Ovis aries) but did not conclusively prove that the responsible pathogens were transmitted from domestic to bighorn sheep. The objective of this study was to determine, unambiguously, whether Mannheimia haemolytica can be transmitted from domestic to bighorn sheep when they commingle. Four isolates of M.

Molecular cloning of interleukin-1β, interleukin-8, and tumor necrosis factor-α of bighorn sheep (Ovis canadensis) and comparison with those of other species.

The susceptibility to, and pathology induced by, Mannheimia haemolytica infection in bighorn sheep (BHS) and domestic sheep (DS) are distinctly different. Bighorn sheep are particularly susceptible to pneumonia caused by M. haemolytica, and the pneumonic lesions in infected BHS are more severe than those in DS.

Differential expression of interleukin-8 by polymorphonuclear leukocytes of two closely related species, Ovis canadensis and Ovis aries, in response to Mannheimia haemolytica infection.

The pneumonic lesions and mortality caused by Mannheimia haemolytica in bighorn sheep (BHS; Ovis canadensis) are more severe than those in the related species, domestic sheep (DS; Ovis aries), under both natural and experimental conditions. Leukotoxin (Lkt) and lipopolysaccharide (LPS) are the most important virulence factors of this organism. One hallmark of pathogenesis of pneumonia is the influx of polymorphonuclear leukocytes (PMNs) into the lungs.

Mycoplasma ovipneumoniae can predispose bighorn sheep to fatal Mannheimia haemolytica pneumonia.

Mycoplasma ovipneumoniae has been isolated from the lungs of pneumonic bighorn sheep (BHS). However experimental reproduction of fatal pneumonia in BHS with M. ovipneumoniae was not successful.

Experimental infection of liver flukes, Fasciola hepatica and Fascioloides magna, in Bison (Bison bison).

This experimental study was conducted to evaluate the susceptibility of American bison (Bison bison) to liver flukes, Fascioloides magna and Fasciola hepatica. Six bison were each experimentally inoculated with 600 metacercariae of Fascioloides magna, and three were later treated with triclabendazole suspension at 40 mg/kg of body weight. Four additional bison were each experimentally inoculated with 600 metacercariae of Fasciola hepatica.

Experimental infection of bighorn sheep with liver flukes (Fasciola hepatica).

Nine Rocky Mountain bighorn sheep (Ovis canadensis canadensis) were each inoculated orally with 250 metacercariae of Fasciola hepatica. Blood and fecal samples were collected at the time of inoculation and at 5, 10, 14, and 20 wk after inoculation. Numbers of fluke eggs in feces, hemoglobin, packed cell volume, and eosinophil values were determined.

Echinococcus granulosus in gray wolves and ungulates in Idaho and Montana, USA.

We evaluated the small intestines of 123 gray wolves (Canis lupus) that were collected from Idaho, USA (n=63), and Montana, USA (n=60), between 2006 and 2008 for the tapeworm Echinococcus granulosus. The tapeworm was detected in 39 of 63 wolves (62%) in Idaho, USA, and 38 of 60 wolves (63%) in Montana, USA. The detection of thousands of tapeworms per wolf was a common finding.

Transmission of lungworms (Muellerius capillaris) from domestic goats to bighorn sheep on common pasture.

Four domestic goats (Capra hircus) that were passing first-stage dorsal-spined larvae of Muellerius capillaris were copastured on a 0.82-ha pasture for 11 mo from May 2003 to April 2004 with seven Rocky Mountain bighorn sheep (Ovis canadensis) that were not passing dorsal-spined larvae. During the 11-mo experiment, two bighorn sheep died from pneumonia caused by Mannheimia (Pasteurella) haemolytica biotype A, serotype 2.

Mannheimia haemolytica serotype A1 exhibits differential pathogenicity in two related species, Ovis canadensis and Ovis aries.

Mannheimia haemolytica causes pneumonia in both bighorn sheep (BHS, Ovis canadensis) and domestic sheep (DS, Ovis aries). Under experimental conditions, co-pasturing of BHS and DS results in fatal pneumonia in BHS. It is conceivable that certain serotypes of M.

Bighorn sheep beta2-integrin LFA-1 serves as a receptor for Mannheimia haemolytica leukotoxin.

Mannheimia haemolytica is an important cause of pneumonia in bighorn sheep (BHS; Ovis canadensis). Leukotoxin (Lkt), the primary virulence determinant of M. haemolytica, induces cytolysis of all subsets of leukocytes.

beta(2) integrin Mac-1 is a receptor for Mannheimia haemolytica leukotoxin on bovine and ovine leukocytes.

Pneumonia caused by Mannheimia haemolytica is an important disease of cattle (BO), domestic sheep (DS, Ovis aries) and bighorn sheep (BHS, Ovis canadensis). Leukotoxin (Lkt) produced by M. haemolytica is cytolytic to all leukocyte subsets of these three species.

Microorganisms associated with a pneumonic epizootic in Rocky Mountain bighorn sheep (Ovis canadensis canadensis).

A comprehensive study of a pneumonic epizootic was initiated when the first signs of disease were noted in a metapopulation of bighorn sheep inhabiting Hells Canyon, bordering Idaho, Oregon, and Washington. A total of 92 bighorn sheep were tested for etiologic agents during the following 6-mo study period. The study population included bighorn sheep believed to be the subpopulation in which disease was first noted, and these sheep were translocated to a holding facility in an effort to contain the disease (group A1, n = 72); bighorn sheep in other subpopulations (group A2) with evidence of clinical disease were captured, sampled, given antibiotics, and released (n = 8) and those that were found dead were necropsied (n = 12).

Bighorn sheep, a new host record for Parelaphostrongylus odocoilei (Nematoda: Protostrongylidae).

Larval nematodes with a dorsal spine on the tail were recovered from fecal samples of California bighorn sheep (Ovis canadensis californiana) in northeastern Washington State, USA. The identity of these dorsal-spined larvae (DSL) was established by single-strand conformation polymorphism (SSCP) analyses of a partial fragment of the first internal transcribed spacer of the ribosomal DNA. The SSCP profiles of individual DSL from bighorn sheep were compared with those of DSL of five protostrongylid species (Parelaphostrongylus andersoni, P odocoilei, P.

Cloning and comparison of bighorn sheep CD18 with that of domestic sheep, goats, cattle, humans and mice.

Previously, we have shown that CD18, the beta-subunit of beta(2)-integrins, serves as a receptor for leukotoxin (Lkt) secreted by Mannheimia (Pasteurella) haemolytica on bovine leukocytes. Anti-CD18 monoclonal antibodies (mAbs) inhibit Lkt-induced cytolysis of bighorn sheep (Ovis canadensis) leukocytes suggesting that CD18 may serve as a receptor for Lkt on the leukocytes of this species as well. Confirmation of bighorn sheep CD18 as a receptor for Lkt, and elucidation of the enhanced Lkt-susceptibility of bighorn sheep polymorphonuclear leukocytes (PMNs), necessitates the cloning and sequencing of cDNA encoding bighorn sheep CD18.

Evaluation of ivermectin for treatment of hair loss syndrome in black-tailed deer.

Since 1997, numerous Columbian black-tailed deer (Odocoileus hemionus columbianus) in western Washington (USA) have developed a hair loss syndrome that often preceded emaciation, debilitation, pneumonia, and death. To study this syndrome, eight affected free-ranging Columbian black-tailed deer fawns were captured from western Washington in February 1999 to determine the effect of ivermectin treatment. Fecal examinations indicated that the internal parasites were Dictyocaulus viviparus, Parelaphostrongylus sp.