Salmonella Typhimurium has been reported to contaminate egg production across the world, but where Salmonella Enteritidis is endemic it is this latter serovar that dominates egg-borne salmonellosis. ...However, Salmonella Typhimurium is a major food-borne pathogen so it is important to understand how it can impact the microbiological safety of eggs and what serovar-specific control strategies may be appropriate in the future as control over Salmonella Enteritidis continues to improve. To that end, the present review examines the published literature on Salmonella Typhimurium in laying hens and eggs, with particular reference to comparative studies examining different serovars. Experimentally Salmonella Enteritidis is more often isolated from egg contents and seems to adhere better to reproductive tract mucosa, whilst Salmonella Typhimurium appears to provoke a more intense tissue pathology and immune response, and flock infections are more transient. However, it is observed in many cases that the present body of evidence does not identify clear differences between specific behaviours of the serovars Typhimurium and Enteritidis, whether in laying hens, in their eggs, or in the laying environment. It is concluded that further long-term experimental and natural infection studies are needed in order to generate a clearer picture.
There is a recent trend to feed pet dogs and cats in Britain and other developed countries on raw meat and animal by‐products using either commercial preparations or home recipes. This shift from ...heat‐treated processed food has been driven by perceived health benefits to pets and a suspicion of industrially produced pet food. The diets of wild‐living related species have been used as a rationale for raw feeding, but differences in biology and lifestyle impose limitations on such comparisons. Formal evidence does exist for claims by raw‐feeding proponents of an altered intestinal microbiome and (subjectively) improved stool quality. However, there is currently neither robust evidence nor identified plausible mechanisms for many of the wide range of other claimed benefits. There are documented risks associated with raw feeding, principally malnutrition (inexpert formulation and testing of diets) and infection affecting pets and/or household members. Surveys in Europe and North America have consistently found Salmonella species in a proportion of samples, typically of fresh‐frozen commercial diets. Another emerging issue concerns the risk of introducing antimicrobial‐resistant bacteria. Raw pet food commonly exceeds hygiene thresholds for counts of Enterobacteriaceae. These bacteria often encode resistance to critically important antibiotics such as extended‐spectrum cephalosporins, and raw‐fed pets create an elevated risk of shedding such resistant bacteria. Other infectious organisms that may be of concern include Listeria, shiga toxigenic
E
scherichia
coli
, parasites such as Toxoplasma gondii and exotic agents such as the zoonotic livestock pathogen Brucella suis, recently identified in European Union and UK raw pet meat imported from Argentina.
Aims: To investigate and compare commercial and farm‐level milling operations in respect of the monitoring and control of Salmonella contamination.
Methods and Results: Four commercial feedmills ...and four on‐farm poultry feed mixers were intensively sampled. Samples included dust and spillages and were cultured for Salmonella. Serovars in ingredients on farms were associated with wildlife and/or livestock, whereas those in commercial mill ingredients were associated with domestically produced cereals and imported vegetable protein. Endemic contamination of two commercial feedmills was reflected in isolates obtained from finished products and destination flocks. Renovation of equipment and chemical treatment of equipment and feed had not removed endemic strains, and previous routine monitoring in the commercial mills had not revealed the degree of contamination found in the present investigations.
Conclusions: Ingredient contamination was diverse and reflected the sources and storage environments used by mills and farms, respectively. The use of dust and spillage samples showed a clear sensitivity advantage over the previously used monitoring methods in the feedmills.
Significance and Impact of the Study: Monitoring for Salmonella contamination of commercial feedmills requires sensitive methods, such as those employed in this study. This is particularly important for endemic contamination.
Salmonella Vaccination in Pigs: A Review Wales, A. D.; Davies, R. H.
Zoonoses and public health,
February 2017, 2017-02-00, 20170201, Letnik:
64, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Summary
The control of Salmonella enterica in pig production is necessary for both public and animal health. The persistent and frequently asymptomatic nature of porcine Salmonella infection and the ...organism's abilities to colonize other animal species and to survive in the environment mean that effective control generally requires multiple measures. Vaccination is one such measure, and the present review considers its role and its future, drawing on studies in pigs from the 1950s to the present day. Once established in the body as an intracellular infectious agent, Salmonella can evade humoral immunity, which goes some way to explaining the often disappointing performance of inactivated Salmonella vaccines. More recent approaches, using mucosal presentation of antigens, live vaccines and adjuvants to enhance cell‐mediated immunity, have met with more success. Vaccination strategies that involve stimulating both passive immunity from the dam plus active immunity in offspring appear to be most efficacious, although either approach alone can yield significant control of Salmonella. Problems that remain include relatively poor control of Salmonella serovars that are dissimilar to the vaccine antigen mix, and difficulties in measuring and predicting the performance of candidate vaccines in ways that are highly relevant to their likely use in commercial production.
Cereal ingredients for animal feedstuffs may become contaminated by Salmonella on their farms of origin. This is often concentrated in multiple foci, owing to contamination by rodents and other ...wildlife which may be missed by routine sampling, and may involve serovars of particular public health significance, such as Salmonella Typhimurium (STM). The study examined such contamination in domestically-produced cereal ingredients in the United Kingdom. Cereal-producing farms with associated cattle or pig enterprises (43) and feedmills (6) were investigated, following the isolation of STM from their premises (feedmills) or STM DT104 from their livestock (farms) by routine surveillance. Cereal samples from feedmills yielded two STM isolates from the same premises, of the same phage types as were isolated from wild bird faeces at ingredient intake and product loading areas. Farm investigations identified numerous Salmonella serovars, including STM, on grain harvesting and handling equipment, in grain storage areas, and in wildlife samples. Mice were removed from one pig farm and shed Salmonella Derby and Salmonella Bovismorbificans for 10 months afterwards. Grain stores more than one kilometre away from livestock areas were rarely found to be contaminated with STM. The principal issues with Salmonella contamination of cereals appeared to be the use of livestock areas as temporary grain stores on cattle farms, and access to stored grain by wildlife and domestic animals.
Common health problems observed during peripartum include milk fever, mastitis, fatty liver disease, ketosis, dystocia, retained placenta, metritis, hypomagnesaemia and abomasal displacements. The ...increased incidence of health problems observed during the periparturient period can be partly attributed to suboptimal immune responses. Factors contributing to decreased periparturient immunity include the act of parturition itself, impaired leukocytic activity, effects of colostrogenesis and lactogenesis, and associated hypocalcemia and negative energy balance. Nutritional and other management strategies represent a relevant short-term strategy aimed at improving the health and welfare of the transitioning cow. Additionally, it is important to consider improving the health of dairy herds through the genetic selection of animals with enhanced robustness by identifying those with superior disease resistance or resilience in the face of infection. As a consequence these animals are better able to cope with the production and environmental stresses. These may provide long-term selection strategies for improving the health and welfare of the transitioning cow particularly when combined with sound management practices, allowing dairy cattle to reach their full genetic potential.
•In this review we propose immune responsiveness as a survival/longevity trait for improving cattle health and welfare at the transition period.
Objective To characterize the natural history of intestinal failure (IF) among 14 pediatric centers during the intestinal transplantation era. Study design The Pediatric Intestinal Failure Consortium ...performed a retrospective analysis of clinical and outcome data for a multicenter cohort of infants with IF. Entry criteria included infants <12 months receiving parenteral nutrition (PN) for >60 continuous days. Enteral autonomy was defined as discontinuation of PN for >3 consecutive months. Values are presented as median (25th, 75th percentiles) or as number (%). Results 272 infants with a gestational age of 34 weeks (30, 36) and birth weight of 2.1 kg (1.2, 2.7) were followed for 25.7 months (11.2, 40.9). Residual small bowel length in 144 patients was 41 cm (25.0, 65.5). Diagnoses were necrotizing enterocolitis (71, 26%), gastroschisis (44, 16%), atresia (27, 10%), volvulus (24, 9%), combinations of these diagnoses (46, 17%), aganglionosis (11, 4%), and other single or multiple diagnoses (48, 18%). Prescribed medications included oral antibiotics (207, 76%), H2 blockers (187, 69%), and proton pump inhibitors (156, 57%). Enteral feeding approaches varied among centers; 19% of the cohort received human milk. The cohort experienced 8.9 new catheter-related blood stream infections per 1000 catheter days. The cumulative incidences for enteral autonomy, death, and intestinal transplantation were 47%, 27%, and 26%, respectively. Enteral autonomy continued into the fifth year after study entry. Conclusions Children with IF endure significant mortality and morbidity. Enteral autonomy may require years to achieve. Improved medical, nutritional, and surgical management may reduce time on PN, mortality, and need for transplantation.
Data on husbandry practices, performance, disease and drug use were collected during a cross-sectional survey of 89 poultry meat farms in England and Wales to provide information on possible risk ...factors for the occurrence of fluoroquinolone (FQ)-resistant bacteria. Faeces samples were used to classify farms as "affected" or "not affected" by FQ-resistant (FQr) Escherichia coli or Campylobacter spp. Risk factor analysis identified the use of FQ on the farms as having by far the strongest association, among the factors considered, with the occurrence of FQr bacteria. Resistant E. coli and/or Campylobacter spp. were found on 86% of the farms with a history of FQ use. However, a substantial proportion of farms with no history of FQ use also yielded FQr organisms, suggesting that resistant bacteria may transfer between farms. Further analysis suggested that for Campylobacter spp., on-farm hygiene, cleaning and disinfection between batches of birds and wildlife control were of most significance. By contrast, for E. coli biosecurity from external contamination was of particular importance, although the modelling indicated that other factors were likely to be involved. Detailed studies on a small number of sites showed that FQr E. coli can survive routine cleaning and disinfection. It appears difficult to avoid the occurrence of resistant bacteria when FQ are used on a farm, but the present findings provide evidence to support recommendations to reduce the substantial risk of the incidental acquisition of such resistance by farms where FQ are not used.
The objectives of this study were to assess antibody and cellular immune responses in first-lactation dairy heifers reared under a pasture-based production system and to investigate associations ...between immune competence and stress responsiveness, health, and productivity. A commercial vaccine was used to induce antibody and cellular immune responses and, based on measured responses, animals were classified as above average, average, and below average for each trait independently and in combination (overall immune competence). Overall immune competence phenotypic rankings were generated by combining standardized residual values for antibody and cellular responses measured in individual heifers. Cortisol responses to handling and yarding were used to assess stress responsiveness, worm egg counts were used to assess internal parasite burden, somatic cell counts to assess udder health and estimates of total daily milk volume, and milk fat and milk protein contents to assess productivity. A total of 393 Holstein-Friesian and Holstein-Friesian × Jersey crossbred heifers from 2 herds practicing seasonal calving in a pasture-fed production system were enrolled in the study. The immune competence phenotypes of individual heifers were assessed before their first mating and their subsequent performance during their first lactation was monitored. Animals with below-average antibody and cellular immune competence had higher serum cortisol concentrations compared with their counterparts following handling, suggesting they had a reduced ability to cope with management-induced stress. Furthermore, a significant negative (favorable) correlation was observed between antibody responses and stress responsiveness. Similarly, correlations between antibody responses and internal parasite burden were significant and negative (favorable). No correlations were observed between overall immune competence and milk yield, milk fat, and milk protein content.
Summary Objective Despite a health care system that is free at the point of delivery, ethnic minorities may not always get care equitable to that of White patients in England. We examined whether ...ethnic differences exist in joint replacement rates and surgical practice in England. Design 373,613 hip and 428,936 knee National Joint Registry primary replacement patients had coded ethnicity in Hospital Episode Statistics. Age and gender adjusted observed/expected ratios of hip and knee replacements amongst ethnic groups were compared using indirect standardisation. Associations between ethnic group and type of procedure were explored and effects of demographic, clinical and hospital-related factors examined using multivariable logistic regression. Results Adjusted standardised observed/expected ratios were substantially lower in Blacks and Asians than Whites for hip replacement (Blacks 0·33 95% CI, 0·31 to 0·35, Asians 0·20 CI, 0·19 to 0·21) and knee replacement (Blacks 0·64 CI, 0·61 to 0·67, Asians 0·86 % CI, 0·84 to 0·88). Blacks were more likely to receive uncemented hip replacements (Blacks 52%, Whites 37%, Asians 44%; P<0·001). Black men and women aged <70 years were less likely to receive unicondylar or patellofemoral knee replacements than Whites (men 10% vs 15%, P=0·001; women 6% vs 14%, P<0·001). After adjustment for demographic, clinical and hospital-related factors, Blacks were more likely to receive uncemented hip replacement (OR 1·43 CI, 1·11 to 1·84). Conclusions In England, hip and knee replacement rates and prosthesis type given differ amongst ethnic groups. Whether these reflect differences in clinical need or differential access to treatment requires urgent investigation.
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