Richard Drolet

Proliferative Enteritis Associated with Lawsonia Intracellularis (Ileal Symbiont Intracellularis) in White-Tailed Deer:

Jang SS, Biberstein EL, Hirsh DC: 1987, Actinobacillus suis15. like organisms in horses. Am J Vet Res 48:1036-1038. Logan EF: 1978, Factors influencing the quantity and quality of colostrum in the cow. Vet Sci Commun 2:39-46. 16. Maxie MG: 1993, The urinary system. In: Pathology of domestic animals, eds. Jubb KVF, Kennedy PC, Palmer N, 4th ed., vol. 2, pp. 501-502. Academic Press, San Diego, CA. Miniats OP, Spinato MT, Sanford SE: 1989, Actinobacillus suis 17. septicemia in mature swine. Two outbreaks resembling erysipelas. Can Vet J 30:943-947. Radostits OM, Blood DC, Gay CC: 1994, In: Veterinary medicine, 8 ed., pp. 124-132. Balliere Tindall, London, UK. Samitz EM, Biberstein EL: 1991, Actinobacillus suis-like organisms and evidence of hemolytic strains of Actinobacillus lignieresii in horses. Am J Vet Res 52:1245-1251. Sanford SE: 1992, Actinobacillus suis. In: Diseases of swine, eds. Leman AD, Straw BE, Mengeling WL, D’Allaire S, Taylor DJ, 7th ed., pp. 633-636. Iowa State University Press, Ames, IA. Wilson WD, Madigan JE: 1989, Comparison of bacteriologic culture of blood and necropsy specimens for determining the cause of foal septicemia: 47 cases (1978-1987). J Am Vet Med Assoc 195:1759-1763.

Partially redundant functions of Adamts1 and Adamts4 in the perinatal development of the renal medulla

Adamts4 encodes a widely‐expressed proteinase thought to be involved in processes ranging from cartilage metabolism to ovarian follicle development. To study its physiological roles, Adamts4‐null mice were created by gene targeting. Unexpectedly, these were found to be phenotypically normal, suggesting that other gene(s) may compensate for its loss. Adamts4−/− mice were, therefore, crossed with a strain lacking Adamts1, whose pattern of expression and substrate specificity overlap that of Adamts4. Most (>95%) Adamts1−/−;Adamts4−/− mice died within 72 hr after birth with a marked thinning of the renal medulla. The renal defect was not observed in embryonic Adamts1−/−;Adamts4−/− kidneys, but became apparent around birth. The few (<5%) Adamts1−/−;Adamts4−/− animals to reach adulthood had the same renal phenotype seen in newborns. This study is thus the first to report Adamts4 expression and function in the mammalian kidney, and to demonstrate that Adamts1 and Adamts4 play redundant and essential roles in perinatal kidney development. Developmental Dynamics 240:1806–1814, 2011.

The Evaluation of Postmortem Ocular Fluid Analysis as a Diagnostic Aid in Sows

This study was undertaken to evaluate the diagnostic usefulness of postmortem ocular fluid analysis in estimating the antemortem status of various serochemical constituents. Chemical values of serum and aqueous and vitreous humors were compared following different procedures. A blood sample and the 2 eyes were collected from each of 100 sows at a nearby abattoir. The results obtained from immediate centrifugation of ocular fluids after sampling were compared with those samples in which centrifugation was delayed by 2 hours. Two different postmortem intervals were used for sampling ocular fluids, 2 and 24 hours. Concentrations of urea, calcium, phosphorus, potassium, sodium, and chloride were determined from serum and humors. Delayed centrifugation did not affect chemical values of ocular fluids nor the relationships between serum and humors. Phosphorus and potassium values increased significantly with the postmortem interval in both aqueous and vitreous humors. The relationships between chemical values of ocular fluids and serum were determined using simple linear regression. There was a poor correlation between ocular fluid and serum values for all electrolytes; a significant correlation was found only for urea concentrations in both humors.

Aplasia cutis congenita (epitheliogenesis imperfecta) in swine: observations from a large breeding herd.

Epitheliogenesis imperfecta has been reported in several animal species, and its inheritance is suspected to be autosomal recessive. This term has been used to describe two different diseases, namely epidermolysis bullosa and aplasia cutis congenita, which are both grossly characterized by an absence of epidermis or mucosal epithelium and are most frequently reported on the distal limbs and oral cavity. Epitheliogenesis imperfecta has been described in swine, but the literature on the subject is scarce. To better characterize this condition, 70 piglets with congenital skin defects macroscopically compatible with epitheliogenesis imperfecta were examined. In all but 1 case, only 1 piglet per litter was affected. Of the affected piglets, 65 (93%) were male, suggesting a sex-related problem. More than half of the piglets had multiple skin lesions. All defects were located on the caudal half of the body, and none was found in the oral cavity. Most lesions were characterized by an absence of epidermis and part of the dermis and adnexae. Adnexal dysplasia was also observed at several sites, both with and without epitheliogenesis imperfecta, suggesting a developmental problem. Fluid-filled, congenital subcutaneous bullae were noted grossly on 7 piglets; their relationship, if any, with epitheliogenesis imperfecta remains unknown. As the term epitheliogenesis imperfecta has been used in cases of epidermolysis bullosa, the term aplasia cutis congenita seems to be more appropriate to describe these lesions in swine.

Optimizing Longevity in Sows and Boars

Longevity of sows and boars affects the productivity and economics of the herd. Implement a culling program that is tailored to the specific needs of the producer and the characteristics of the farm. Evaluate the removal policies regularly, estimate the longevity of breeding animals, calculate the nonproductive sow days associated with culling, and determine the major causes of culling and death. Once a longevity problem and its extent have been identified, the underlying problems and predisposing factors can be more easily corrected.

Spontaneous glomerulonephritis in swine

In this investigation, 32 cases of naturally occurring glomerulonephritis in swine were studied retrospectively (1973–1993). Almost all affected pigs were crossbred and more than half were growing pigs. Nearly two thirds of the pigs showed gross renal lesions characterized by bilateral kidney enlargement, palor, edema, and/or cortical petechiation. The most commonly encountered extrarenal lesions were serous bodily effusions and gastric ulcers. The renal disease was considered the primary cause of death in 11 pigs. Histologically, the renal lesions in all pigs were characterized by a generalized and global proliferative glomerulonephritis. Mesangioproliferative glomerulonephritis was diagnosed in 2 pigs, whereas the glomerular lesions found in the other pigs (30/32) were characterized by a proliferative and exudative glomerulonephritis frequently associated with crescent formation. In all pigs, there was histologic evidence of proteinuria. A focal necrotizing vasculitis was found in the kidneys of 7 pigs. Although probably of immune origin, the precise etiopathogenesis of the porcine glomerulonephritis described herein after remains unknown.

Determination of Halothane Gene Mutation Associated with Malignant Hyperthermia in Sows Dead of Cardiac Failure

Significant losses due to sow mortality may be encountered in some swine breeding herds. Many conditions are responsible for death in sows; some, however, are more common Several investigations showed that cardiac failure is among the major causes of death in breeding females, accounting for up to 31% of the mortalities. 1,4,17,19,20 Parturition, heat stress, mating, fighting, and transport were identified as predisposing factors for cardiac failure in sows housed in total confinement. 1-6 Most of these events, which are demanding for the cardiovascular system, are also considered triggering factors for the development of malignant hyperthermia (MH) in pigs, a genetically transmitted disease. Differentiating a simple case of cardiac failure from MH might be difficult because these 2 conditions share many clinical and pathologic similarities. Recently, MH in swine, also called porcine stress syndrome (PSS), has been associated with a recessive mutation in the gene coding for porcine calcium release channel, also called the ryanodine receptor gene (ryr-1 locus) or halothane gene (Hal), which is located on chromosome 6. With molecular biology techniques, it is now possible to identify pigs that are MH susceptible, MH carrier, and norma1. The aim of this retrospective study was to determine if cases of cardiac failure in sows could be attributed to the defective gene responsible for MH. Formalin-fixed, paraffin-embedded tissues from 84 sows previously collected in a study on sow mortality in Canada were used in the present investigation. From these selected sows, 42 were identified to have died of cardiac failure and 42 died of various other causes (control group), such as torsions of abdominal organs, cystitis-pyelonephritis, gastric ulcers, and uterine prolapse. Paraffin-embedded tissue blocks from heart, skeletal muscle, liver, spleen, and kidney were used to determine the Hal genotype by a polymerase chain reaction (PCR) technique. 11,22 For each sow, a 10-μm-wide section was prepared from tissue blocks, and excess paraffin was trimmed. Sections were placed in 1.5-ml sterile microfuge tubes. The microtome blade, tweezers, and other equipment that could come into contact with the samples were carefully sterilized before processing each tissue block. Tissue sections were deparaffinized with toluene and washed twice with ethanol to remove the solvent. Ethanol was allowed to evaporate under vacuum for 10 minutes. To isolate genomic DNA, 100 μl of digestion buffer (50 mM Tris [pH

Pathology of ear hematomas in swine.

The objectives of our study were to describe the pathology of ear hematomas in swine and to add to the comprehension of the pathogenesis of this condition. The pathogenesis of aural hematomas has been studied mainly in dogs; however, disagreements exist about the precise anatomic location of the hemorrhage. Sixteen pigs with ear hematoma at various stages of development were included in this study. The pigs were submitted for routine autopsy for various and unrelated reasons over a period of several years. Based on gross examination, the 16 cases of aural hematomas were subjectively classified as acute (n = 6), subacute (n = 3), and chronic (n = 7). The age of the animals at the time of autopsy ranged from 2 weeks to adulthood, with all acute cases being <7 weeks of age. Morphologic examination of all acute cases revealed that the hematoma developed predominantly in a subperichondral location on both sides of the cartilaginous plate simultaneously. Within these same cases, there were also some areas in which blood-filled clefts had formed within the cartilage itself. Besides fibroplasia, neoformation of cartilage was found to represent a significant part of the repair process. All chronic cases were characterized on cross-section of the ear by the presence of at least 2 distinct, wavy, focally folded, and roughly parallel plates of cartilage separated from each other by fibrous tissue.