Nipah virus infection among abattoir workers in Malaysia, 1998-1999.
(41/502)
BACKGROUND: An outbreak of encephalitis primarily affecting pig farmers occurred during 1998-1999 in Malaysia and was linked to a new paramyxovirus, Nipah virus, which infected pigs, humans, dogs, and cats. Because five abattoir workers were also affected, a survey was conducted to assess the risk of Nipah infection among abattoir workers. METHODS: Workers from all 143 registered abattoirs in 11 of 13 states in Malaysia were invited to participate in this cross-sectional study. Participants were interviewed to ascertain information on illness and activities performed at the abattoir. A serum sample was obtained to test for Nipah virus antibody. RESULTS: Seven (1.6 %) of 435 abattoir workers who slaughtered pigs versus zero (0%) of 233 workers who slaughtered ruminants showed antibody to Nipah virus (P = 0.05). All antibody-positive workers were from abattoirs in the three states that reported outbreak cases among pig farmers. Workers in these three states were more likely than those in other states to have Nipah antibody (7/144 [4.86%] versus 0/291 [0%], P < 0.001) and report symptoms suggestive of Nipah disease in pigs admitted to the abattoirs (P = 0.001). CONCLUSIONS: Nipah infection was not widespread among abattoir workers in Malaysia and was linked to exposure to pigs. Since it may be difficult to identify Nipah-infected pigs capable of transmitting virus by clinical symptoms, using personal protective equipment, conducting surveillance for Nipah infection on pig farms which supply abattoirs, and avoiding handling and processing of potentially infected pigs are presently the best strategies to prevent transmission of Nipah virus in abattoirs. (+info)
Relationships between behavioral and meat quality characteristics of pigs raised under barren and enriched housing conditions.
(42/502)
In this study the effects of barren vs enriched housing conditions of pigs on their behavior during the lairage period (2-h holding period before slaughter), carcass characteristics, postmortem muscle metabolism, and meat quality were studied. The barren housing system was defined by common intensive housing conditions (i.e., with slatted floors and recommended space allowances), whereas the enriched environment incorporated extra space and straw for manipulation. Salivary cortisol concentrations were measured before transport and at the end of the lairage period. During the lairage period the percentage of time spent walking and fighting by the pigs was registered. Carcass characteristics such as weight, meat percentage, and backfat thickness were determined. At 5 min, 45 min, 4 h, and 24 h postmortem, pH, temperature, and lactate concentrations were determined in the longissimus lumborum (LL) and biceps femoris (BF) muscles. Capillarization of the muscle, mean muscle fiber area, and color and drip loss after 2 and 5 d of storage were determined for both muscle types. Pigs from the barren environment had a significantly higher increase in cortisol from farm to slaughter, but no differences in behavior were observed during the lairage period. Carcass characteristics did not differ between pigs from barren and those from enriched housing conditions. Postmortem lactate formation was significantly lower in LL muscles of enriched pigs at 4 and 24 h postmortem. Capillary density and mean muscle fiber area did not differ between the groups of pigs. The percentage of drip loss at 2 and 5 d after storage of LL muscle samples from enriched-housed pigs was significantly lower than that of the barren-housed pigs. Similar tendencies were found for the BF muscle from pigs kept in an enriched environment, but these were not statistically significant. The housing system did not affect meat color. It is concluded that on-farm improvement of animal welfare by environmental enrichment can also lead to beneficial economic effects after slaughter by improving the water-holding capacity of pork. (+info)
Spore survival during batch dry rendering of abattoir waste.
(43/502)
Normal batch dry rendering practice does not ensure sterile products, because bacterial spores are protected against thermal denaturation by the high fat-low water content environment which results from drying the materials at temperatures below those required for sterilization. (+info)
Use of a marker organism to model the spread of central nervous system tissue in cattle and the abattoir environment during commercial stunning and carcass dressing.
(44/502)
Due to concerns about a link between variant Creutzfeldt-Jakob disease in humans and similar prion protein-induced disease in cattle, i.e., bovine spongiform encephalopathy (BSE), strict controls are in place to exclude BSE-positive animals and/or specified risk materials including bovine central nervous system (CNS) tissue from the human food chain. However, current slaughter practice, using captive bolt guns, may induce disruption of brain tissues and mobilize CNS tissues into the bovine circulatory system, leading to the dispersion of CNS tissues (including prion proteins) throughout the derived carcass. This project used a marker (antibiotic-resistant) strain of Pseudomonas fluorescens to model the effects of commercial captive bolt stunning procedures on the movement of mobilized CNS material within slaughtered animals and the abattoir environment. The marker organism, introduced by injection through the bolt entry aperture or directly using a cartridge-fired captive bolt, was detected in the slaughter environment immediately after stunning and in the abattoir environment at each subsequent stage of the slaughter-dressing process. The marker organism was also detected on the hands of operatives; on slaughter equipment; and in samples of blood, organs, and musculature of inoculated animals. There were no significant differences between the results obtained by the two inoculation methods (P < 0.05). This study demonstrates that material present in, or introduced into, the CNS of cattle during commercial captive bolt stunning may become widely dispersed across the many animate and inanimate elements of the slaughter-dressing environment and within derived carcasses including meat entering the human food chain. (+info)
A survey of Nipah virus infection among various risk groups in Singapore.
(45/502)
Following the Nipah virus (NV) outbreak in March 1999 in Singapore, a serological survey was undertaken to screen individuals potentially exposed to NV. Blood samples were tested for NV IgM, IgG and neutralizing antibodies. Twenty-two (1.5%) of 1469 people tested had antibodies suggesting NV infection. Although 12 of the 22 infected people (54.6%) were symptomatic, the remaining 10 (45.4%) were clinically well and had no past history of compatible pulmonary or neurological disease. Clinical and serological findings suggested three people had been infected with NV before the outbreak was recognized. All those who were infected were male abattoir workers. None of the people who had contact with horses, and no healthcare workers exposed to infected patients and their specimens had detectable antibodies. This study provides evidence that NV causes asymptomatic infection. All of the antibody positive individuals had direct contact with pigs and there was no evidence of human to human transmission. (+info)
Prevalence of Enterocytozoon bieneusi in swine: an 18-month survey at a slaughterhouse in Massachusetts.
(46/502)
Slaughterhouse pig samples were analyzed by PCR for Enterocytozoon bieneusi infection. Thirty-two percent were found to be positive, with rates being higher over the summer months. Three isolates from pigs were identical in their ribosomal internal transcribed spacer sequence to human E. bieneusi type D, two were identical to type F (from a pig), and nine were previously unreported. The viability of these spores was demonstrated by their ability to infect gnotobiotic piglets. The presence of the infection in liver was shown by in situ hybridization. (+info)
Reflectance spectrum of adipose tissue to trace grass feeding in sheep: influence of measurement site and shrinkage time after slaughter.
(47/502)
The signature of carotenoid pigments stored in the caudal fat has been used to discriminate carcasses of lambs raised on pasture from those fed concentrates. However, the literature reports higher concentration of carotenoids in perirenal than in caudal fat, and it is likely that carotenoid concentration in fat increases with shrinkage time. Our objectives were to investigate the effects of measurement site and shrinkage time after slaughter on the reliability of the discrimination between grass- and concentrate-fed lambs. Thirty-two lambs were fed concentrate-based diets (stall, n = 16) or grazed a natural pasture in France (grass, n = 16). The concentrate supply was regulated to have similar ADG between the two treatments. Periodically lambs weighing about 35 kg were slaughtered. Reflectance spectrum and lightness (L*), redness (a*), and yellowness (b*) were measured at slaughter and after 24 h of shrinkage in the subcutaneous caudal and in the perirenal fat. The spectra were translated to have a value of reflectance at 510 nm = 0 and the integral of the translated spectrum was calculated between 450 and 510 nm (i.e., the zone of light absorption by carotenoids). The integral value of subcutaneous caudal fat at slaughter differed between stall- and grass-fed lambs (P < 0.05) but was not reliable to discriminate between feeding treatments. After 24-h shrinkage, the discrimination was better but was uncertain for 50% of the lambs. The integral value of perirenal fat at slaughter allowed us to discriminate all the lambs fed concentrates (16) from all those fed pasture (16). After 24-h shrinkage, the discrimination based on perirenal fat was partially compromised; 21.9% of the animals were not correctly discriminated. The integral value of the translated spectrum was highly (P < 0.001) correlated with the fat yellowness (b*), but the b* value was not reliable to discriminate between feeding treatments. However, plotting yellowness (b*) against redness (a*) values allowed us to discriminate 31 out of 32 lambs. Measuring reflectance spectrum of perirenal fat at slaughter allowed for complete discrimination of grass-fed from stall-fed lambs. However, because the integral values were affected by shrinkage time, measurements should be rigorously made immediately after slaughter. (+info)
The use of passive injectable transponders in fattening lambs from birth to slaughter: effects of injection position, age, and breed.
(48/502)
A total of 1,159 Tiris half-duplex passive injectable transponders (PIT) of 32-mm length were used to study the electronic identification of 618 fattening lambs of two breeds used for different production purposes (Ripollesa, meat breed, n = 271, and Manchega, dairy breed, n = 347). The lambs were s.c. injected in the armpit and the retro-auricular positions at 2, 15, and 30 d of age. All lambs were also tagged with a small plastic ear tag after birth. A group of 76 lambs were injected only in the right armpit and were kept for breeding. The PIT losses, breakages, and electronic failures were evaluated at weekly weight recordings throughout the fattening period using two types of hand-held transceivers. Fattened lambs were harvested in a commercial abattoir between 3 and 4 mo of age when they reached market weight (11 to 12 kg hot carcass weight). The total number of PIT that fell or broke in the slaughtering line, the location method, and the recovery time were recorded. On the farm PIT losses were not affected (P > 0.05) by age at injection, injection position, or breed. Mean losses of PIT and ear tags during the same period were 5% and 6.3%, respectively (P > 0.05). No PIT breakages or failures were observed during the fattening period. Mean recovery of PIT in the abattoir (85.6%) was affected (P < 0.05) by breed and injection position. Losses of PIT in the abattoir were greater (P < 0.05) in the Ripollesa breed (18.4%) than in Manchega (10.0%), and for both breeds losses were greater (P < 0.05) in the retro-auricular than in the armpit positions (18.6 vs 10.8%, respectively). The percentage of PIT broken during slaughtering was low (0.3%). The mean recovery times (18 +/- 2 s) were not affected (P > 0.05) by breed, injection position, or age, thus allowing a harvesting speed of 200 lambs/h on average. In conclusion, the injection of 32-mm PIT into the armpit or the retro-auricular region is not recommended as a practice for the electronic identification of fattening lambs, even though they perform similarly to small plastic ear tags. This is partly a consequence of the PIT losses observed on the farm but mainly because of the difficulties with recovering the PIT in the abattoir. More research will determine whether the use of smaller transponders or injection in other positions could improve their performance in fattening lambs. (+info)