Four multistate outbreaks of human Salmonella infections associated with live poultry contact, United States, 2009

Outbreaks of human salmonellosis associated with live poultry contact have been reported since 1955. Multiple Salmonella serotypes have been associated with these outbreaks, and specific outbreak strains have been repeatedly linked to single hatcheries over multiple years. During 2009, four multistate outbreaks of human Salmonella infections associated with direct and indirect exposure to live poultry purchased from mail-order hatcheries and agricultural feed stores were identified, resulting in 165 culture-confirmed cases in 30 states. This report describes the epidemiologic, environmental and laboratory investigations conducted by state and local health departments, state departments of agriculture, the U.S. Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS), National Poultry Improvement Plan (NPIP) and National Veterinary Services Laboratories (NVSL), and the Centers for Disease Control and Prevention (CDC). Case-patients were identified through PulseNet, the national molecular subtyping network for foodborne disease surveillance, and interviewed using the CDC standard live poultry contact questionnaire that asks about poultry-related exposures during the 7 days before illness onset. These outbreaks highlight the need to focus efforts on strategies to decrease and prevent human illness associated with live poultry contact through comprehensive interventions at the mail-order hatchery, agricultural feed store and consumer levels. Additional consumer education and interventions at mail-order hatcheries and venues where live poultry are sold, including agricultural feed stores, are necessary to prevent transmission of Salmonella from poultry to humans.     

Gross postmortem and histologic examination findings from abortion losses and calf mortalities in western Canadian beef herds

Production losses from abortions, stillbirths, and early calf mortality were described for the 2002 calf crop in 203 beef herds in western Canada. A total of 1689 calves were examined. A summary diagnosis was reported for 64% of aborted calves, 78% of stillborn calves, 88% of neonatal calves, and 94% of the calves > 3 d of age. Diagnoses for aborted calves included: thyroid gland lesions, pneumonia, developmental anomalies, placentitis, and myocardial necrosis or myopathy. For stillborn calves, diagnostic findings included: dystocia, thyroid gland lesions, myocardial necrosis or myopathy, developmental anomalies, and skeletal myopathy or necrosis. The most common diagnoses for neonatal calves (≤ 3 d) were: pneumonia, skeletal myopathy or necrosis, myocardial necrosis or myopathy, accident or trauma, and septicemia. For older calves (3 d to 3 mo), the most common diagnoses included: starvation, abomasal ulcer or perforation, enteritis or colitis, pneumonia, and intestinal volvulus, obstruction, or perforation.     

Presence of arsenic resistance in Salmonella enterica serovar Kentucky and other serovars isolated from poultry

A collection of 125 Salmonella enterica poultry isolates (71 serovar Kentucky isolates, and the remainder belonging to serovars Alachua, Enteritidis, Hadar, Heidelberg, Montevideo, Mbandaka, Senftenberg, Typhimurium, and Worthington) were tested for the ability to grow on tryptic soy agar containing sodium arsenite [As(III)] or arsenate [As(V)]. All serovar Kentucky isolates and 18 of the non-Kentucky isolates were able to grow in the presence of 0.1 mM As(III), and 69 grew in the presence of 1 mM As(V). Thirty of the non-Kentucky isolates did not grow at these As(III) and As(V) concentrations, but seven grew at 1 mM As(III) and 10 mM As(V). PCR-based analysis demonstrated the presence of arsB and arsD sequences in all Kentucky isolates, whereas one or both of these sequences were present in only 30 of the other isolates. It remains to be determined if these arsenic-resistance determinants benefit Salmonella exposed to man-made arsenic-containing compounds in poultry environments.     

Pathological and aetiological studies of multifocal interstitial nephritis in wasted pigs at slaughter

Multifocal interstitial nephritis in pigs has been associated with several infectious agents. The objective of the present study was to investigate several different potential infectious agents associated with "white-spotted" kidneys in pigs suffering from wasting at slaughter (aged 6-8 months). Twenty-nine case kidneys (with a "white-spotted" gross appearance) classified into 3 macroscopic lesional grades, and 15 control kidneys (lacking gross lesions), were obtained from a pig abattoir. Laboratory analyses to detect potential associations with the aforementioned pathological condition with Leptospira spp., porcine circovirus type 2 (PCV2), porcine parvovirus (PPV), porcine reproductive and respiratory syndrome virus (PRRSV), and bacteria, were carried out. Microscopically, interstitial nephritis with a lymphofollicular inflammatory pattern (follicular nephritis) was observed in both case and control kidneys, with a higher frequency seen in the former ones. No leptospires were identified, although antibodies to the Pomona and Bratislava serovars were detected. Some pyogenic bacteria were also isolated from both case and control kidneys. PCV2 nucleic acid was only detected in 1 case kidney. PRRSV antigen was not found in any tested sample. Some pigs were tested positive for PPV by serology. Apparently, none of the studied agents were specifically associated as being the potential cause of the renal lesions in the studied wasted pigs. The fact that these chronic lesions may have been the consequence of a previous infection with one of these studied microorganisms, or more, and eventually with other non-tested infectious agents during the growing-finishing period, cannot be ruled out.     

Results of allergen-specific immunotherapy in 117 dogs with atopic dermatitis

The success of the treatment of 117 dogs with atopic dermatitis with allergen-specific immunotherapy for up to 48 months was assessed. An excellent response (remission with exclusive immunotherapy) was recorded in 18 of the dogs, a good response (more than 50 per cent reduction in medication and improvement of clinical signs) was recorded in 57, a moderate response was recorded in 24 and a poor response in 18. The mould antigens in the allergen extract were stored in a separate vial before administration and the success rate of the immunotherapy including mould antigens was much higher than in an earlier study in which mould and pollen antigens had been stored in one vial. The success rate was not affected significantly by the age of the dogs when the disease developed, or by their age or the period for which they had shown clinical signs when the treatment began; it was also unaffected by whether pollens, moulds or dust mites were used as antigens, or by whether the offending allergens had been identified by intradermal testing or by serum testing for allergen-specific immunoglobulin E.     

Evaluation of platelet aggregation using a point-of-care instrument in retired racing Greyhounds

Veterinarians involved in Greyhound rescue have anecdotally observed that 10-15% of Greyhounds bleed profusely after simple surgical procedures. In most patients, platelet counts and hemostasis profiles are normal; therefore, it is possible that these dogs have platelet dysfunction. The PFA-100 is a novel point-of-care platelet function analyzer that has recently been evaluated as a rapid method to assess platelet function in dogs. The objectives of this study were to characterize platelet function in a group of healthy Greyhounds by means of the PFA-100. Blood samples were collected from the jugular vein from 30 healthy Greyhounds. CBC, biochemical profile, PFA-100 assay with collagen/epinephrine (COL-EPI) and collagen/ adenosindiphosphate (COL-ADP), plasma von Willebrand factor antigen concentration (vWF:Ag), and vWF collagen-binding assay (vWF:CBA) were performed. PFA-100 closure times (CTs) with COL/ADP ranged from 63 to 92 seconds (mean +/- SD, 74.7 +/- 7.9 seconds) and with COL/EPI from 87 to 238 seconds (138 +/- 41 seconds); vWF: Ag ranged from 22 to 120% (87.52 +/- 25.5%) and vWF: CBA ranged from 36 to 102% (77.4 +/- 17.3%); and platelet counts ranged from 147 to 265 x 10(9)/L (194.6 +/- 31.64 x 10(9)/L). Greyhound CTs were significantly shorter than CTs in a mixed population of 50 healthy non-Greyhound dogs, in which the COL/ADP CTs ranged from 61 to 172 seconds (mean +/- SD, 87 +/- 21.6 seconds), and the COL/ EPI CTs ranged from 81 to 300 seconds (mean +/- SD, 183 +/- 67.6 seconds; P = 0.005 for COL/ADP CT; P = 0.001 for COL/ EPI CT). Also, platelet counts were significantly lower (P = 0.001) and packed cell volume was significantly higher (P = 0.001) in the Greyhound than in the non-Greyhound group. The PFA-100 is a reproducible method that can be used in the clinical setting to assess platelet function in Greyhounds; however, normal CTs in healthy Greyhounds are shorter than in other breeds. The results obtained in this study will be used to screen for abnormal platelet function in Greyhounds with postoperative bleeding.     

Ultrastructure of the gastrocnemius tendon and sheath from broilers infected with reovirus

Gastrocnemius tendon and sheath from male broilers infected with reovirus at 1 day of age were evaluated ultrastructurally at 1, 2, 3, 4, 5, 10, 15, and 20 weeks postinoculation (PI). Although virus particles were not identified, degenerative changes in sheath and tendon fibroblasts were characterized by cytoplasmic vacuolization, disruption of membranes, and loss of ribosomes from rough endoplasmic reticulum, mitochondrial degeneration, and cell disruption.