Cryptosporidium ryanae n. sp. (Apicomplexa: Cryptosporidiidae) in cattle (Bos taurus)

A new species, Cryptosporidium ryanae, is described from cattle. Oocysts of C. ryanae, previously identified as the Cryptosporidium deer-like genotype and recorded as such in GenBank (AY587166, EU203216, DQ182597, AY741309, and DQ871345), are similar to those of Cryptosporidium parvum and Cryptosporidium bovis but smaller. This genotype has been reported to be prevalent in cattle worldwide. Oocysts obtained from a calf for the present study are the smallest Cryptosporidium oocysts reported in mammals, measuring 2.94-4.41micromx2.94-3.68microm (mean=3.16micromx3.73microm) with a length/width shape index of 1.18 (n=40). The pre-patent period for two Cryptosporidium-na?ve calves fed C. ryanae oocysts was 11 days and the patent period was 15-17 days. Oocysts were not infectious for BALB/c mice or lambs. Fragments of the SSU-rDNA, HSP-70, and actin genes amplified by PCR were purified and PCR products were sequenced. Multi-locus analysis of the three unlinked loci demonstrated the new species to be distinct from all other species and also demonstrated a lack of recombination, providing further evidence of species status. Based on morphological, molecular and biological data, this geographically widespread parasite found only in Bos taurus calves is recognized as a new species and is named C. ryanae.     

Complications associated with the use of vascular access ports in dogs receiving external beam radiation therapy

OBJECTIVE: To assess the perioperative and postoperative complications associated with use of vascular access ports (VAPs) in the jugular and lateral saphenous veins of dogs requiring frequent anesthetic episodes for radiation therapy. DESIGN: Cohort study. ANIMALS: 40 dogs referred to a veterinary teaching hospital. PROCEDURES: VAPs were used in 23 dogs, and intravenous catheters inserted in a peripheral vein were used in 17 dogs. The frequency of perioperative and postoperative complications associated with VAP use and the frequency of infection associated with intravenous catheter use were recorded. Results of bacterial culture of VAP tips and amount of time required for VAP placement and removal and for anesthetic induction were also recorded. RESULTS: VAP-associated perioperative complications included malposition of the catheter tip in 4 of 23 (17.4%) dogs. The VAP-associated postoperative complications included seroma formation in 7 (30.4%) dogs, breakage of port-anchoring sutures in 3 (13.0%) dogs, suspected fatal catheter-related septicemia in 1 (4.3%) dog, and temporary partial withdrawal occlusion in 18 of 255 (7.1%) anesthetic episodes. CONCLUSIONS AND CLINICAL RELEVANCE: Placement of VAPs provided ready access in dogs receiving radiation therapy. Most complications were minor and self-limiting; however, a low risk of serious complications existed. Use of fluoroscopy to assess position of the catheter tip is recommended to decrease the risk of malposition. Immediate removal of a VAP is recommended when clinical signs of infection develop. Removal of a VAP at the completion of radiation therapy should be performed unless the benefit of continued vascular access outweighs the risks.     

Immunoglobulin A multiple myeloma with cutaneous involvement in a dog

An 8-year-old rottweiler, diagnosed with multiple myeloma and multiple sites of cutaneous involvement, was treated with chemotherapy and radiation therapy. The diagnostic criteria for canine multiple myeloma, limitations of diagnostic testing for light chain proteinuria in dogs, and the role of radiation therapy in multiple myeloma patients is discussed.     

Interaction of transforming growth factor-beta-1 with alpha-2-macroglobulin from normal and inflamed equine joints.

Binding between equine plasma alpha-2-macroglobulin (alpha 2M) and several cytokines known to participate in inflammatory reactions in other species was initially examined. Plasma was obtained from 5 horses with various abnormalities. Samples, both untreated and after reaction with methylamine, were incubated with exogenous, radiolabeled, porcine-derived transforming growth factor-beta-1 (125I-TGF-beta 1), recombinant human interleukin-1-beta (125I-IL-1 beta), and recombinant human tumor necrosis factor-alpha (125I-rhTNF-alpha). They were then subjected to nondenaturing polyacrylamide gel electrophoresis (PAGE). Binding of the native (slow) and activated (fast) forms of alpha 2M to each cytokine was subjectively evaluated with autoradiography. Equine alpha 2M bound 125I-TGF-beta 1. However, poor or no binding was observed between alpha 2M and either of 125I-rhTNF-alpha or 125I-IL-1 beta. Synovial fluid was then obtained from 6 normal horses, 6 horses with septic arthritis, and 6 horses with degenerative joint disease. Untreated and methylamine-reacted samples were quantitatively examined for binding with 125I-TGF-beta 1, using the autoradiographic techniques described above and densitometry. Native and activated alpha 2M were also quantified by densitometry of PAGE gels. Native alpha 2M was significantly elevated in septic arthritis (6.4% to 29.5% of total protein detected) and degenerative joint disease (2.8% to 12.3%), compared to normal joints (0.9% to 4.2%). Activated alpha 2M, however, was not detected in untreated synovial fluid samples. In all plasma and joint fluid samples, whether untreated or reacted with methylamine, 125I-TGF-beta 1 bound predominantly to alpha 2M, and preferentially to the activated form of alpha 2M. In synovial fluid, the amount of 125I-TGF-beta 1 binding was proportional to the quantity of alpha 2M present. These results indicate that: 1) equine alpha 2M binds TGF-beta 1; 2) the native form of alpha 2M is present in both equine plasma and synovial fluid, and 3) alpha 2M is a major binding protein for TGF-beta 1 in equine synovial fluid. Therefore, alpha 2M may play a role in regulating this mediator of inflammation in equine joints.     

Giardia and Cryptosporidium species and genotypes in coyotes (Canis latrans).

Feces and duodenal scrapings were collected from 22 coyotes (Canis latrans) killed in managed hunts in northeastern Pennsylvania. Polymerase chain reaction (PCR) methods were used to detect Giardia and Cryptosporidium spp. PCR-amplified fragments of Giardia and Cryptosporidium spp. SSU-rRNA genes were subjected to DNA sequence analysis for species/genotype determination. Seven coyotes (32%) were positive for G. duodenalis: three assemblage C, three assemblage D, and one assemblage B. Six coyotes (27%) were positive for Cryptosporidium spp. One isolate shared 99.7% homology with C. muris, whereas five others (23%) shared 100% homology with C. canis, coyote genotype. This is the first report on multiple genotypes of Giardia spp. in coyotes and on the prevalence of Cryptosporidium spp. genotypes in coyotes.     

Use of a free cortical ulnar autograft following en bloc resection of a mandibular tumor

A dog was presented for the en bloc resection of a previously irradiated mandibular ossifying epulis. A central hemimandibulectomy was performed, and the mandibular defect was stabilized by the use of a free cortical ulnar autograft and rigid internal fixation. The dog had normal mastication and left forelimb function two weeks after surgery. Radiographic evaluation of the surgical site at three and 10 months after surgery showed normal bony healing.     

Prevalence of Cryptosporidium, Giardia and Eimeria infections in post-weaned and adult cattle on three Maryland farms

The prevalence of Cryptosporidium, Giardia and Eimeria, in healthy, asymptomatic, post-weaned and mature cattle was investigated on three Maryland farms. One farm, a dairy research facility, had 150 multiparous Holstein milking cows; 24 were examined and Cryptosporidium andersoni was detected in three (12.5%) but neither Giardia nor Eimeria was detected. The second farm, a commercial dairy, had 57 multiparous Holstein milking cows and an equal number of heifers. Of 19 cows examined, C. parvum, Giardia duodenalis, and Eimeria bovis and/or E. ellipsoidalis were detected in two (10.5%), two (10.5%) and one (5.26%) cow, respectively. Of 23 heifers examined, C. parvum, Giardia, and E. bovis and E. ellipsoidalis, was detected in two (8.7%), four (17.4%), and five (21.7%), heifers, respectively. The third farm, a beef cattle breeding and genetics research facility, had 180 7- to 9-month old purebred black Angus. Of 118 examined for C. parvum and Giardia, 34 (28.8%) and 44 (37.3%) were positive, respectively, of 97 examined for E. bovis and/or E. ellipsoidalis 32 (33.0%) were positive. These findings, based on a method with a minimum detection level of 100 oocysts of C. parvum/g of feces, which underestimates the number of infected cattle, clearly demonstrate the presence of low level, asymptomatic infections in post-weaned and adult cattle in the United States and indicate the potential role of such cattle as reservoirs of infectious parasites.     

Prevalence of Giardia duodenalis genotypes in adult dairy cows

The prevalence of Giardia duodenalis genotypes was determined in adult dairy cows. Fecal specimens were collected from two farms each in Vermont, New York, Pennsylvania, Maryland, Virginia, North Carolina, and Florida. Specimens, cleaned of fecal debris and concentrated using CsCl density gradient centrifugation, were subjected to PCR and DNA sequence analysis. The prevalence of G. duodenalis infection, ranged from 3% to 64%, with an average prevalence of 27% (144 positive cows out of 541 examined). DNA sequence analysis of the 16S rRNA gene revealed the presence of both Assemblage A and Assemblage E, G. duodenalis. Overall, Assemblage E was present in 25% of all animals tested and Assemblage A was present in 2% of the animals. As a percentage of G. duodenalis isolates, Assemblage E represented 94% and Assemblage A represented 6%. Although, most of the cows were infected with a genotype that is not known to be infectious for humans, adult cows on five farms did harbor varying levels of zoonotic Assemblage A, G. duodenalis. Therefore, although adult cows do not appear to be a significant source of human infectious cysts in the environment, the risk from this age group should not entirely be discounted.