Clinical, radiographic, endoscopic, bronchoalveolar lavage and lung biopsy findings in horses with exercise-induced pulmonary hemorrhage

A clinical study was performed to determine whether clinical, endoscopic, radiographic, bronchoalveolar lavage (BAL) cytological, and pulmonary biopsy findings could be correlated in horses with exercise-induced pulmonary hemorrhage (EIPH) compared with controls. Racing standardbred horses were selected as either EIPH (n = 10) or control (n = 10), based on repeated postexertional endoscopy of the lower airways. Complete physical and respiratory examinations were performed and blood samples were submitted for arterial blood gas analysis, hematologic study, and fibrinogen determination. Bilateral chest radiographs were taken with the horse standing, and a BAL sample was obtained for cytological examination. Lung was biopsied transcutaneously. Weighted scores were calculated for clinical, radiographic, and pulmonary biopsy findings. The conclusion was that only routine physical examination may help the clinician when EIPH is suspected in horses, especially when there are abnormal findings on percussion of the caudodorsal areas of the chest.     

Cytokine induction in pulmonary airways of horses with heaves and effect of therapy with inhaled fluticasone propionate

Work in humans and laboratory animals has identified a central role for cytokines and chemokines in development and persistence of lower airway inflammation. The objectives of this study were to determine interleukin (IL)-1 beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha induction in bronchoalveolar lavage (BAL) of control horses and horses with heaves both during remission and exacerbation of the disease, and to determine the effect of therapy with inhaled fluticasone propionate on the cytokine profile of horses with heaves. IL-1 beta and TNF-alpha mRNA expression was significantly higher in horses with heaves after exposure to moldy hay compared to either values obtained during clinical remission or to healthy controls. IL-8 mRNA expression and protein concentrations were significantly higher in horses with heaves than in controls. Both IL-4 and IFN-gamma mRNA expression was increased at various times in heaves-susceptible horses compared to controls. IL-2, IL-5 and IL-10 mRNA expression was not detected in BAL cells of either group. Therapy with inhaled fluticasone propionate after induction of a severe heaves exacerbation resulted in complete resolution of clinical signs, normalization of pulmonary function tests, and significant decrease in BAL neutrophilia. This was associated with a significant decrease in IL-4 mRNA expression and increase in IFN-gamma/IL-4 ratio in horses with heaves. These results demonstrate the clinical efficacy of inhaled fluticasone propionate for the treatment of heaves and suggest a role for cytokines in the development of lower airway inflammation in heaves-susceptible horses.     

Risk factors associated with colic in horses

Many factors have been identified as risk factors for colic in horses in several epidemiological studies. The aim of our paper was to review the results of 12 epidemiological studies, in order to assess the impact of each risk factor for colic. According to the literature, the factors that increase the risk of colic are feeding practices (type and quality of food, type and changes of feeding), the intrinsic factors of horses (sex, age and breed), management (type and changes of housing and activity), medical history (a previous colic, administration of a medical treatment) and parasite control (the presence of worms and type of deworming program). Several individual factors were incriminated as risk factors by all the studies. Nevertheless, the different studies did not always agree on the role of other risk factors. The conclusions were tightly related to several criteria in the selection of the study population, like the type of the epidemiological study, the number and the origin of horses included and the location of the study.     

Mechanisms controlling the oxygen consumption in experimentally induced hypochloremic alkalosis in calves

The study was carried out on healthy Friesian calves (n = 10) aged between 10 and 30 days. Hypochloremia and alkalosis were induced by intravenous administration of furosemide and isotonic sodium bicarbonate. The venous and arterial blood samples were collected repeatedly. 2,3-diphosphoglycerate (2,3-DPG), hemoglobin and plasmatic chloride concentrations were determined. The red blood cell chloride concentration was also calculated. pH, PCO2 and PO2 were measured in arterial and mixed venous blood. The oxygen equilibrium curve (OEC) was measured in standard conditions. The correspondence of the OEC to the arterial and mixed venous compartments was calculated, taking blood temperature, pH and PCO2 values into account. The oxygen exchange fraction (OEF%), corresponding to the degree of blood desaturation between the arterial and mixed venous compartments and the amount of oxygen released at the tissue level by 100 mL of blood (OEF Vol%) were calculated from the arterial and mixed venous OEC, combined with PO2 and hemoglobin concentration. Oxygen delivery (DO2) was calculated using the arterial oxygen content, the cardiac output measured by thermodilution, and the body weight of the animal. The oxygen consumption (VO2) was derived from the cardiac output, OEF Vol% and body weight values. Despite the plasma hypochloremia, the erythrocyte chloride concentration was not influenced by furosemide and sodium bicarbonate infusion. Due to the alkalosis-induced increase in the 2,3-DPG, the standard OEC was shifted to the right, allowing oxygen to dissociate from hemoglobin more rapidly. These changes opposed the increased affinity of hemoglobin for oxygen induced by alkalosis. Moreover, respiratory acidosis, hemoconcentration, and the slight decrease in the partial oxygen pressure in mixed venous blood (Pvo2) tended to improve the OEF Vol% and maintain the oxygen consumption in a physiological range while the cardiac output, and the oxygen delivery were significantly decreased. It may be concluded that, despite reduced oxygen delivery, oxygen consumption is maintained during experimentally induced hypochloremic alkalosis in healthy 10-30 day old calves.     

Monoclonal gammopathies in the dog: a retrospective study of 18 cases (1986-1999) and literature review

Eighteen dogs with monoclonal gammopathies were evaluated retrospectively. Most of the cases were associated with lymphoproliferative tumors (i.e., nine multiple myelomas, one Waldenstr?m's macroglobulinemia, one lymphoma, one chronic lymphocytic leukemia, and one mucocutaneous plasmacytoma). The prevalence of nonmyelomatous monoclonal gammopathies (28%) was also significant (three leishmaniasis and two ehrlichiosis). Presenting complaints and clinical signs often were nonspecific or related to bleeding diathesis. Significant laboratory findings included proteinuria, hypoalbuminemia, and anemia. Some unusual features were also observed: a multiple myeloma with immunoglobulin M secretion, another myeloma with two narrow spikes on the electrophoretic pattern, and a mucocutaneous plasmacytoma secreting an immunoglobulin G paraprotein.     

Urinary cortisol as an additional tool to assess the welfare of pregnant sows kept in two types of housing

The use of urinary cortisol (UC) as an additional tool to evaluate sows welfare was assessed in two experiments. In a preliminary methodological experiment, the kinetics of cortisol excretion in urine was studied during an Adreno Cortico Trophic Hormone (ACTH) challenge test in 10 pregnant sows. In a second experiment, 96 primiparous sows of an experimental unit were assigned to two different housing systems: 48 animals were housed in individual pens (IP) and 48 animals in collective pens (CP) with 6 animals per pen. UC was measured at the beginning and at the end of pregnancy and compared with other welfare indicators such as behaviour or skin damage. In both experiments, UC was measured using a high pressure liquid chromatography assay. In experiment 1, UC was constant on the day before injection of ACTH, with no variations related to circadian rhythm. It began to rise 2 h after the injection, peaked between 2 to 5 h after then returned to the basal concentration on the day after the injection. In experiment 2, UC concentrations were not different between CP- and IP-housed sows but they were higher in sows exhibiting the less stereotypies in comparison with sows exhibiting the most stereotypies. The results of this study suggest that UC is a good indicator of acute stress, more convenient than plasma cortisol measurement since it is a non-invasive method avoiding restraint or catheterisation of sows. They also suggest that UC could also give additional information on the assessment of chronic stress and improve the evaluation of animal welfare if used in conjunction with other welfare indicators.     

Evaluation of Parameters Accounting for Phomopsis Resistance Using Natural Infection and Artificial Inoculation on Recombinant Inbred Lines From a Cross Between Susceptible and Resistant Sunflower

HA89, a sunflower line susceptible to Phomopsis, was crossed with a resistant line, LR4-17. Two hundred and forty-one F2/F3 progenies and 232 recombinant inbred (RI) lines were derived from this cross. F2/F3 progenies were tested in semi-natural infections in 1994. F7, F8 and F9 were tested with semi-natural infections in 1997, 1998 and 1999, respectively. F7 RI lines were artificially infected with Phomopsis mycelium on leaves in 1997. Family effects were significant in F2/F3 progenies for attack rates on stems and encircling spots rates on stems after semi-natural infections. Line effects were significant for attack rates on stems and encircling spot rates in F7 and F8. F7 RI lines showed a high heritability for speed of necrosis on leaf blades after artificial infection. Continuous and unimodal distributions were observed for attack rates on stems in all experiments done in semi-natural conditions. In contrast, speed of necrosis on leaf blades showed a bimodal distribution. Significant rank correlations were observed between the speed of necrosis on leaf blades and the attack rates on stems. It is suggested that resistance to Phomopsis is the consequence of several mechanisms, independently inherited. It was concluded that speed of necrosis on leaf blades in artificial infections and attack rates on stems in natural infections should be retained as parameters for quantitative trait locus mapping of Phomopsis resistance.     

Toxin Profile, Fertility and AFLP Analysis of Fusarium verticillioides from Banana Fruits

Gibberella fujikuroi is composed of at least nine mating populations (MPs), corresponding to biological species and assigned letters (from A to I). Each MP possesses a specific toxicological profile and a preferential host. Members of Fusarium verticillioides and F. thapsinum, anamorphs respectively of MPs A (G. moniliformis) and F (G. thapsina), share identical morphological traits, but they have a different preferential hosts (maize and sorghum, respectively) and toxin profiles, beingable the only member of MP A to produce fumonisins and the only member of MP F to produce moniliformin. Isolates from banana fruits were identified morphologically as F. verticillioides. The isolates were analyzed for fumonisin and moniliformin production. While none of the isolates produced fumonisin, all the isolates produced moniliformin. The isolates were crossed with tester strains of MPs A and F, showing ability to produce fertile perithecia only when crossed by MP A tester strains isolated from maize. However, the time required for the formation of fertile perithecia and their size differed significantly from the usual fertile crosses of strains belonging to MP A. Pathogenicity tests using such isolates of F. verticillioides isolated from banana and a set of F. verticillioides isolates isolated from maize were also performed on banana fruits. The data showed that the isolates from banana were more pathogenic. Finally, isolates from banana and maize were compared using AFLP. The results revealed that isolates from banana and maize produced two distinctly different clusters. In conclusion, isolates of F. verticillioides from banana showed specific traits (toxin production, in vitro fertility, pathogenicity and molecular profiles), that were different to those of the same species from maize. This could reflect important differences in the ecology and natural history of the population from banana and should encourage further investigations into the mechanisms of toxin production and pathogenicity within the same MP.     

Infectious diseases of the central nervous system.

Neurologic disease is seen commonly in cats, with infectious causes accounting for 30-45% of cases. However, since a specific infection cannot be identified in 12-40% of these cases, it is essential that we try to understand these cases better in the hope that we can eventually identify the cause(s), and so determine how best to treat and/or prevent them.     

Immunologic disorders in neonatal foals.

Foals live in an environment heavily populated by bacteria, many of which are capable of causing disease. Development of infection,however, is the exception rather than the rule. The ability of the foal to prevent infection by most pathogens is the result of a sophisticated set of defense mechanisms. These defense mechanisms can be divided into adaptive and innate immunity. Innate immunity encompasses defense mechanisms that pre-exist or are rapidly induced within hours of exposure to a pathogen. Conversely, adaptive or acquired immunity represents host defenses mediated by T and B lymphocytes, each expressing a highly specific antigen receptor and exhibiting memory during a second encounter with a given antigen. Immunologic disorders are relatively common in foals compared with their occurrence in adult horses. This article summarizes the current understanding of the equine fetal and neonatal immune system and reviews common immunodeficiency disorders as well as disorders resulting from allogenic incompatibilities.