Flow cytometric immune profiling of specific-pathogen-free chickens before and after infectious challenges

Broilers and layer chickens have been intensively selected for production parameters. This selection has affected immune capacity. Consequently, the fine-tuning of immune responses is becoming important for maximum productivity. Flow cytometry is a recurrent technology used for the immunophenotyping of birds. Studies, however, have focused on the mechanism of specific diseases or have used animals whose immunological condition could be biased-by vaccination or environmental stressors, for example. The aim of this study was to evaluate the immune status of specific-pathogen-free birds across different age ranges to characterize the natural changes that occur over time. Additionally, specific-pathogen-free chickens were challenged with four infectious agents, allowing identification of the subpopulations of peripheral blood immune cells that are consistently altered under various conditions. Several lymphocyte subsets vary naturally with aging, so the interpretation of results using animals of different age ranges must proceed with care. Parameters such as CD8(+)CD28(-), CD8αα(+), CD4(+)CD8(+), and CD8(+)TCRVβ1(+) have been shown to be valuable in understanding immune changes during disease. The use of these data allows a determination of the consistency of cytometric parameters under various conditions, which should ease the interpretation of immunophenotyping and the future application of cytometric analysis in the poultry industry.     

Laparoscopic cryptorchidectomy and ovariectomy in standing horses using the EnSeal® tissue-sealing device

In the present series of cases, 8 laparoscopic cryptorchidectomies and 4 laparoscopic ovariectomies were carried out in sedated standing horses. Sedation involved a lesser anaesthesiological risk than does general anaesthesia. As compared to laparotomic exposure, the minimally invasive laparoscopic intervention provided better visualisation, shorter operative time and faster recovery. The blood vessels supplying the testes and ovaries and the suspensory ligaments of the organs were sealed and cut with EnSeal?, an adaptive bipolar electrosurgical blood vessel- and tissue-sealing device. The clinical use of the blood vessel- and tissue-sealing device proved to be successful in all cases. Gradual separation of the intact tissue from the treated, compacted, dehydrated and homogenised tissue areas and occlusion of the lumen of blood vessels treated with the device could be observed in all histological sections. To the best of our knowledge, this is the first report on the use of EnSeal? for laparoscopic cryptorchidectomy and ovariectomy in horses.     

Effect of stock type characteristics and time of planting on field performance of aspen (Populus tremuloides Michx.) seedlings on boreal reclamation sites

Aspen (Populus tremuloides Michx) has great potential as a reclamation species for mining sites in the boreal forest, but planting stock has shown poor field performance after outplanting. In this study we tested how different aspen seedling characteristics and planting times affect field outplanting performance on reclamation sites. We produced three different types of aspen planting stock, which varied significantly in seedling size, root-to-shoot ratio (RSR), and total non-structural carbohydrate (TNC) reserves in roots, by artificially manipulating shoot growth during seedling production. All three stock types were then field-planted either in late summer, late fall, or early spring after frozen storage. Seedlings were outplanted onto two reclaimed open-pit mining areas in the boreal forest region of central and east-central Alberta, Canada, which varied significantly in latitude, reclamation history, and soil conditions. Overall, height growth was better in aspen stock types with high RSR and TNC reserves. Differences in field performance among aspen stock types appeared to be more strongly expressed when seedlings were exposed to more stressful environmental site conditions, such as low soil nutrients and moisture. Generally, aspen seedlings planted with leaves in the summer showed the poorest performance, and summer- or fall-planted seedlings with no shoot growth manipulation had much greater stem dieback after the first winter. This indicates that the dormancy and hardening of the stem, as a result of premature bud set treatments, could improve the outplanting performance of aspen seedlings, particularly those planted during summer and fall.     

Occurrence of antibodies to Toxoplasma gondii and Lepstospira spp. in manatees (Trichechus inunguis) of the Brazilian Amazon

The presence of Toxoplasma gondii and Leptospira spp. antibodies was investigated in 74 manatees (Trichechus inunguis [Mammalia: Sirenia]) kept in captivity in two rescue units in the northern region of Brazil. Antibodies to T. gondii were detected in 29 (39.2%) of 74 animals by using the modified agglutination test (titer, 1:25). For antibodies against Leptospira spp., sera were diluted 1:50 and tested against 24 strains ofleptospires by microscopic agglutination microtechnique, and positive samples were end titrated. Twenty-three (31.1%) of 74 animals were reactive to four serovars (Patoc 21/23, Castellonis 2/23, Icterohaemorrhagiae 1/23, and Butembo 1/ 23), with titers ranging from 100 to 1,600. This is the first report of antibodies against T. gondii and Leptospira spp. in T. inunguis from the Brazilian Amazon.     

Radiographic and scintigraphic evaluation of the third carpal bone of control horses and horses with carpal lameness

We compared the radiographic and scintigraphic findings in the third carpal bone of horses performing different work disciplines and investigated their relationship with lameness. Horses had undergone carpal radiography including acquisition of a dorsoproximal-dorsodistal oblique (DPr-DDiO) image of the distal row of carpal bones and/or scintigraphic examination of the carpi. Cause of lameness, breed, age, and work discipline were recorded. Increased opacity in the third carpal bone was graded, ratio of radiopharmaceutical uptake calculated objectively, and increased radiopharmaceutical uptake graded subjectively. Relationships between radiographic, scintigraphic, and clinical findings were assessed statistically. Increased opacity in the third carpal bone (P = 0.003) and ratio of radiopharmaceutical uptake (P = 0.015) were associated with the work discipline. Increased opacity in the third carpal bone was associated with both increased radiopharmaceutical uptake grade (P = 0.002; rs = 0.59) and ratio of radiopharmaceutical uptake (P = 0.013; rs = 0.46). Increased radiopharmaceutical uptake and increased opacity in the third carpal bone were not always observed concurrently. Lameness related to the middle carpal joint was associated with increased opacity (P < 0.001), ratio of radiopharmaceutical uptake (P = 0.037), and increased radiopharmaceutical uptake grade (P < 0.001). Radiographic and scintigraphic abnormalities were observed in horses performing all disciplines, indicating that high-speed exercise may not be the only factor determining the development of osseous disease in the third carpal bone. Both increased opacity and increased radiopharmaceutical uptake were more likely to be seen in horses with lameness related to the middle carpal joint than in horses with other sources of pain.     

Risk factors for equine laminitis: a systematic review with quality appraisal of published evidence

Epidemiological studies into the risk factors for naturally-occurring equine laminitis are limited. There are a small number of such studies, although the results are inconsistent and remain disputed. The reasons for the conflicting results remain unclear. The aim of this review was to critically evaluate previous research in order to identify publications which provide the best evidence of risk factors for naturally-occurring equine laminitis. A systematic review of English language publications was conducted using MEDLINE (1950-2010), CAB Direct (1910-2010) and IVIS (1997-2010). Additional publications were included by searching bibliographies. Search terms included laminitis, equine, risk factors and epidemiology. Publications which compared a case population to a control population and made inferences about parameters as risk factors for naturally-occurring equine laminitis were included. Information was extracted using predefined data fields, including 18 study quality indicators. In total, 17 publications were fully appraised. Six were considered to provide the most reliable information about risk factors for naturally-occurring laminitis. Information on signalment was well researched and there was good evidence for an association with chronic laminitis and increasing age. There remain inconsistent results for many other horse-level risk factors including gender, breed and bodyweight. Previous publications estimating risk factors for equine laminitis were of reasonable quality, although they were limited in the number and scope of the risk factors studied. High-quality, evidence-based studies are needed to identify further risk factors and to establish consensus over previously identified risk factors for different equine populations.