Serological response of experimental ponies orally infected with Ehrlichia risticii

Ten healthy, mature ponies were orally infected with Ehrlichia risticii using Ehrlichia-infected P388D1 mouse monocyte tissue culture cells. Seven developed signs of equine ehrlichial colitis including fever, depression, anorexia, reduced borborygmi, increased abdominal hyperresonance, and diarrhoea. Three remained clinically normal apart from early fever in one. Indirect fluorescent antibody titres were detected in the clinically affected ponies by Days 12 to 17 post infection and increased rapidly to high levels (1:640 to 1:5120) which were maintained until the end of the observation period (Day 28 post infection). Mean antibody titres significantly increased from Days 12 to 14 and from Days 14 to 17 post infection. The rapid increase in antibody titre which occurs close to first appearance of clinical signs may explain the insignificant rise in antibody titres in many naturally occurring cases.

Prevalence of Chlamydia trachomatis cervical infection in a college gynecology clinic: relationship to other infections and clinical features

A total of 479 sexually active college women presenting for routine gynecologic care were screened for gonorrheal and chlamydial infection of the cervix. Most of these women were asymptomatic; those with symptoms had minor complaints related to the lower genital tract. A direct fluorescent antibody test (DFA) showed the prevalence of chlamydial infection to be 8.1%, while culture for Neisseria gonorrhoeae indicated that the prevalence of gonorrhea was 1.5%. DFA-positive women had some minor alterations in the appearance of their cervix, but only 10% had overt mucopurulent cervicitis. The presence of purulent cervical discharge was four times more common in DFA-positive women, but only one-fourth of positive women had this finding. The use of an endocervical gram stain showing ten or more white cells per oil immersion field (x970) did not appear to be clinically useful in diagnosing suspected chlamydial infection because there was no significant difference in the number of white cells seen in specimens from DFA-positive (16 polymorphonuclear leukocytes) and DFA-negative women (ten polymorphonuclear leukocytes). Thus, use of the gram stain as an initial screening mechanism would not markedly reduce the number of women to be tested for Chlamydia trachomatis; half of all women met the gram-stain criterion, and nearly a quarter of the DFA-positive women would be overlooked.

Hepatic failure in dairy cattle following mastitis or metritis

Hepatic failure developed following mastitis or metritis in five adult cows. In all five cases, cows initially showed clinical signs compatible with endotoxemia, which resolved with appropriate therapy for the mastitis or metritis. Subsequently, signs of liver failure developed including profound anorexia, weight loss, cessation of milk production, and in one case, photosensitization. Four cows had laboratory evidence of liver disease and failure (abnormally prolonged sulfobromophthalein [BSP] clearance half-life and abnormally high serum liver enzyme activity). Hepatocellular necrosis or vacuolization was seen on histopathologic examination of liver specimens from all five cows. The hepatocellular necrosis, in some cases, was thought to be due to the direct or indirect effects of endotoxin on the liver. Three of the cows responded to symptomatic therapy. One cow failed to respond and one was not treated.

Equine ehrlichial colitis: effect of oxytetracycline treatment during the incubation period of Ehrlichia risticii infection in ponies

Equine ehrlichial colitis was experimentally induced in 18 ponies, using Ehrlichia risticii-infected blood. Four ponies (group 1) were treated with oxytetracycline (6.6 mg/kg of body weight, IV, q 12 h), beginning 14 hours before inoculation and continuing for 5 days after inoculation. Four additional ponies (group 2) were treated similarly for 10 days after inoculation. The remaining 10 ponies were used as nontreated, infected controls. Clinical disease was delayed in 3 group-1 ponies and in 4 group-2 ponies. Protective immunity developed in the remaining pony that did not develop clinical disease and in 1 group-1 pony and 2 group-2 ponies that developed mild, transient clinical signs.

Site specific effects of acute exercise on muscle and adipose tissue metabolism in sedentary female rats

The effects of endurance exercise on muscle, and adipose tissue metabolism were investigated. Female lean Zucker rats swam for two hours at high intensity. Three groups were examined: pre-exercise control (C), exercised (E) and 24 hours post-exercise (E-24). Exercise increased fat cell lipolysis in the inguinal depot (p less than 0.05) while no effect was detected in the parametrial depot. In contrast, parametrial pad lipoprotein lipase (LPL) activity decreased after exercise with 24 hours post-exercise values being reduced below E and C rats (p less than 0.05). Gastrocnemius LPL activity remained unchanged during exercise while heart LPL increased, E having higher values than C and E-24 (p less than 0.05). Gastrocnemius, but not heart, citrate synthase activity increased with exercise, with E-24 values increased compared to E and C (p less than 0.05). These results demonstrate that adipose tissue's response to exercise is site specific, and suggests a distinct physiological role for different adipose depots. Muscle LPL and citrate synthase activities were modified differently for gastrocnemius and heart, confirming the distinct metabolic response to exercise of these two muscles.

Clinical and hematologic variables in ponies with experimentally induced equine ehrlichial colitis (Potomac horse fever)

The clinical and hematologic variables of 10 ponies with experimentally induced equine ehrlichial colitis (EEC; syn: Potomac horse fever) were studied for a 30-day period (6 ponies) or until death (4 ponies). The earliest clinical sign indicative of EEC was fever (rectal temperature exceeding 39 C). All ponies became depressed (CNS) at various times during the disease, and 90% of the ponies developed diarrhea between 9 and 15 days after infection was induced. The most significant hematologic change was an increase in plasma protein concentration after the onset of fever (P less than 0.05). The PCV in all ponies became increased above base line during the diarrheic phase of EEC. Forty percent of the ponies developed anemia (PCV less than or equal to 23%) during the study. White blood cell counts were highly variable, with 80% of the ponies developing leukopenia (WBC less than 5,000/microliters) during the illness and 60% of the ponies developing leukocytosis (WBC greater than 14,000/microliters) after leukopenia was observed. Differential WBC changes varied widely and included neutropenia with a left shift, lymphopenia, and eosinopenia. Serial thrombocyte counts, which were done for only 1 pony, identified the development of marked thrombocytopenia. Some hematologic changes in ponies with EEC were similar to those reported in canine monocytic and equine granulocytic ehrlichioses. These data are discussed in the context of the pathogenesis and differential diagnosis of EEC.

Equine ehrlichial colitis (Potomac horse fever): recognition of the disease in Pennsylvania, New Jersey, New York, Ohio, Idaho, and Connecticut

Equine ehrlichial colitis (Potomac horse fever), a newly identified colitis of the horse, was first recognized in Maryland. In this report, we document occurrence of the disease in Pennsylvania, New Jersey, New York, Ohio, Idaho, and Connecticut. Enzootic areas were recognized by a characteristic pattern. Frequently there was a seasonal pattern and high prevalence of sporadic colitis in unstressed horses. The attack rate per farm generally was low. Horses on pasture, as well as those stabled, were affected. Clinical signs varied from fever and depression to severe diarrhea and laminitis. Occasionally horses developed profound ileus and severe colic. Diagnosis was based on detection of an increase or decrease in serum antibody titers to Ehrlichia risticii, using an indirect fluorescent antibody technique.

Effects of exercise training on regional adipose tissue metabolism in pregnant rats

To investigate the effects of intense exercise training on maternal adiposity and fetal development, normal lean Zucker (Fa/Fa) rats were divided into three groups: control nonpregnant (CNP), control pregnant (CP), and exercise-trained pregnant (TRP). Trained rats swam three continuous hours per day, 6 days/wk, throughout pregnancy. Food efficiency increased with pregnancy, the highest values being observed during the last trimester of the gestation period. On day 21, pup number, weight, and body composition were similar for CP and TRP. By day 21 of gestation, in both TRP and CP rats, inguinal adipose tissue weight, cell size, and lipoprotein lipase (LPL) activity increased; although TRP values were smaller (P less than 0.05). In CP rats, parametrial and retroperitoneal adipose tissue weights, cell size, and LPL activities increased throughout pregnancy, whereas TRP values were similar to CNP (P less than 0.05). Parametrial fat cell lipolysis showed, however, no effect of training. These results indicate that the extensive energy expenditure occurring during endurance training selectively reduced the dams' adiposity in a regionally specific fashion without any apparent alteration in pup development. The increased substrate utilization required by training during pregnancy did not, however, modify fat cell lipolysis but rather prevented lipid filling through suppression of LPL activity of some depots.

Salmonella shed by horses with colic

Salmonella was isolated from 13 of 100 colicky horses admitted to a referral hospital. Seven horses were shedding the microorganism at or soon after hospital admission. A unique serotype was introduced into the hospital by a horse not shedding Salmonella at admission. It was concluded that 8 horses were infected before admission. Whether the remaining 5 horses were infected before or after admission could not be determined. Salmonella senftenberg was the most commonly isolated serotype from colicky horses and from horses with salmonellosis that were not colicky on hospital admission during the survey period. This organism was rarely isolated at the hospital before initiation of this survey.

Metastasis of bile ductule carcinoma in a cow

An 8-year-old Holstein cow was referred with a history of weight loss, poor milk production, and hyperfibrinoginemia. Laboratory evaluation showed high gamma-glutamyltransferase activity, prolonged sulfobromophthalein clearance half-time, and prolonged prothrombin and partial thromboplastin times. Multiple firm nodules with histologic evidence of bile ductule carcinoma were found on exploratory laparotomy and liver biopsy. Pulmonary and lymph node tumor metastases were extensive. Tumor development in this case could not be associated with any of the known contributing factors in ruminants. This case demonstrates the extensive metastatic potential of this tumor and nonspecific signs with which bovine hepatic disease can be manifested.

Antibiotic susceptibilities of Salmonella species isolated at a large animal veterinary medical center: a three year study

The antibiograms of 408 Salmonella species isolated from large animals were collected during a three year study from 1981 through 1983. The predominant Salmonella serogroup among these isolates was group B. A consistently high percentage of all isolates were resistant to ampicillin and tetracycline. A pattern of increasing resistance to chloramphenicol and gentamicin was documented for serogroup B isolates while the susceptibility of the isolates to neomycin increased. There was a decrease in the incidence of susceptibility to sulfamethoxazole-trimethoprim among the group E isolates. These changes were not as remarkable, nor as alarming, as the overall decreased susceptibility to chloramphenicol and gentamicin. An evaluation of the principles concerning use of antimicrobial agents in veterinary medicine for treatment of Salmonella infections is recommended.

Gastrointestinal diseases of foals

Few foals escape gastrointestinal disease during the first weeks of life. Diarrhea is an extremely common problem; fortunately, however, it is usually mild and self-limiting. When it is not, the underlying cause is often an infectious agent, such as rotavirus or Salmonella spp. Our understanding of many of the infectious agents causing neonatal diarrhea is far from complete. Gastric and duodenal ulcers are a less common disease of neonatal foals. There has been an apparent increase in the incidence of ulcer disease in foals during the past few years. The most effective way of decreasing serious gastrointestinal disease in foals is through the use of good management practices. Environmental and dietary stress must be minimized, and good hygienic practices should be followed. Unfortunately, the needs of the neonate are often ignored, while attention is focused on the mare during the breeding season.

Comparison of rectal mucosal cultures and fecal cultures in detecting Salmonella infection in horses and cattle

Bacteriologic cultures of 65 rectal mucosal samples and 335 fecal samples from 53 horses and 5 cattle shedding Salmonella were performed. Salmonella spp were isolated from 34 (52%) rectal mucosal samples, 21 (32%) concurrent fecal samples, and 150 (45%) total fecal samples. The use of rectal mucosal samples when compared with concurrently obtained fecal samples significantly (P less than 0.025) improved the ability to isolate Salmonella spp. Concurrent bacteriologic culture of rectal mucosal samples and fecal samples resulted in 39 (60%) isolations. Compared with a series of fecal samples, Salmonella was isolated significantly more often when rectal mucosa and feces were cultured concurrently. Salmonella was isolated from rectal mucosal samples when it was not isolated from feces.

Adipoblasts from the Zucker fafa rat

In vitro experiments using both primary fetal hepatocyle cultures and adipoblast cultures have demonstrated that the presence of the fa gene is associated with decreased synthetic capacity, when compared to wild-type cultures. These results are in contrast to the elevated lipogensis and lipoprotein-lipase activities found in vivo in young adult obses (fafa) Zucker rats compared to their lean littermates. These studies used adipoblast cultures to address three possible explanations for these in vitro-in vivo differences: 1) FaFa and fafa adipoblast cultures represent different cell populations with intrinsically different abilities to differentiate, ie, to lipid-fill. 2) The decreased synthetic capacities in fafa vs FaFa adipoblast cultures are specific to cultures derived from the epididymal pad. 3) Cultured adipoblasts produce factor(s) that affect adipoblast differentiation in vitro. Results indicate that 1) the rate of differentiation is slower in fafa than in FaFa adipoblasts 2) there are depot-related differences in lipid metabolism, but these differences do not negate the in vitro association between the fa gene and decreased synthetic capacity and 3) FaFa epididymal-derived adipoblasts produce a factor(s) that affects inguinal-derived adipoblast differentiation and/or growth in vitro. Thus it is important to take both the site of cell origin and culture conditions into consideration when using in vitro systems as an approach to understanding complex in vivo disorders, such as obesity in the Zucker fafa rat.

Perforated abomasal ulcers in adult dairy cows

Case records of adult dairy cattle with abomasal ulcers admitted to the University of Pennsylvania from 1968 through 1980 were evaluated. Of 6,385 adult dairy cattle admitted during that period, 69 had abomasal ulcers of clinical importance. Of 43 ulcers that had perforated, 17 were associated with local peritonitis and 22 were associated with diffuse peritonitis; 4 had perforated so recently that peritonitis had not had time to develop. Perforated ulcers were found in 40 cows that had recently calved (32 cows with ulcers that had perforated within 4 weeks after calving) and often had concurrent disease(s) (39 cows with at least one other disease). Ten cows with local peritonitis survived, whereas only 2 of the cows with diffuse peritonitis survived.

Toxic hepatic failure in newborn foals

Eight foals, 2 to 5 days of age, with similar clinical signs and laboratory and pathologic findings, died from hepatic failure. The predominant clinical signs were depression and icterus. Abnormally high values were found for plasma ammonia content, aromatic-to-branch-chain amino acid ratio, total serum bilirubin content, gamma glutamyl transferase activity, alkaline phosphatase activity, and PCV; partial thromboplastin time and prothrombin time were prolonged. Some foals had high sorbitol dehydrogenase activity. These laboratory findings were suggestive of subacute hepatic disease and failure. Predominant pathologic findings were limited to the liver and brain. The livers were less than half the expected size for 2- to 5-day-old foals, had prominent bile ductule proliferation, hepatic cell necrosis, and mild periportal fibrosis. These findings suggested both prenatal and postnatal diseases caused by exposure to a hepatoxin. The predominant lesion in the brain was the presence of Alzheimer type II astrocytes, which are characteristic of hepatoencephalopathy. Although the periportal fibrosis was suggestive of in utero exposure to a toxin, epidemiologic information suggested that the hepatic failure more likely resulted from oral inoculation of a microorganism culture product at birth. The same disease was reproduced in 2 newborn foals by feeding this product.

Bleeding abomasal ulcers in adult dairy cattle

Case records of abomasal ulcers in adult dairy cattle admitted to the University of Pennsylvania during a 12-year period were reviewed. The only records retrieved were those for cases in which the clinical signs were directly associated with gastrointestinal bleeding. Of 6,385 adult cows admitted during the study period, 69 had clinical ulceration. Twenty-four were bleeding ulcers: 12 nontumor-associated bleeding ulcers and 12 lymphosarcoma-associated bleeding ulcers. Nontumor-associated bleeding ulcers were commonly found in young cows (7 cows less than or equal to 4 years old) that often had concurrent postparturient disease conditions. Lymphosarcoma-associated bleeding ulcers were found more commonly in older cows (10 cows greater than or equal to 6 years old) during all stages of lactation, often without concurrent diseases (8 cows).

Fecal leukocytes and epithelial cells in horses with diarrhea

Fecal samples from 74 horses with diarrhea were examined microscopically for leukocytes and epithelial cells. The diarrhea was categorized as either acute (less than two weeks) or chronic, Salmonella positive or negative, and mild or severe (based on the fecal consistency). A large number of fecal leukocytes was strongly suggestive of salmonellosis; however, approximately 1/3 of the horses with Salmonella-negative diarrhea also shed fecal leukocytes. Fecal leukocytes were more common in horses with acute and/or severe diarrhea regardless of cause. Numbers of fecal colonic mucosal epithelial cells were increased in severe diarrhea, and their presence in horses with chronic diarrhea was correlated with salmonellosis. The study supports the concept that fecal leukocytes and epithelial cells occur in increased numbers in equine salmonellosis but also occur in other types of diarrhea.

Primary cultures of fetal hepatocytes from the genetically obese Zucker rat: protein synthesis

Primary fetal hepatocytes derived from Zucker rats with expected fa gene frequencies of 0.0 and 0.75 have been established and can be used to detect early effects of the fa gene on hepatocellular metabolism. Paired incubation experiments demonstrate that protein synthesis in 0.75 fa gene cultures is significantly less than in 0.0 fa gene cultures under basal conditions. Insulin stimulates protein synthesis in 0.0 fa gene cultures but has no effect on 0.75 fa gene cultures. Cycloheximide inhibits protein synthesis in both types of culture. NH4Cl inhibits protein synthesis in 0.0 but not in 0.75 fa gene cultures. These data suggest that fetal hepatocytes bearing the fa gene have in vitro a generally sluggish anabolic capacity and a blunted capacity to respond to insulin compared to fetal hepatocytes without the fa gene. These diminished capacities may be expression of a genetic error in lysosomal function.

Sympathetic inhibition of thermogenesis in the infant rat: possible glucostatic control

Nonshivering thermogenesis (NST) was examined during cold exposure (30 degrees C) in 5-day-old rats, during food deprivation. NST in the fed state doubled the O2 consumption observed at neutral temperatures. With fasting, the additional O2 consumption stimulated by cold dropped to that observed at thermoneutrality within 6 h, and colonic temperature (Tco) dropped concomitantly. Blood glucose (BG) concentration was halved. Oxygen consumption and Tco in the cold varied linearly with BG changes during food deprivation. 6-Hydroxydopamine transiently stimulated norepinephrine release and elevated metabolism nonadditively with cold stimulation in fed animals, and also stimulated O2 consumption. The drug also partially restored BG concentration, after it had declined during fasting. NST and BG were also restored by gastric infusion of glucose. These data suggest that the decline of NST, and the subsequent hypothermia during food deprivation, is in large part a sympathetically mediated reflex response to low cerebral BG concentration. However, glucose injection in doses sufficient to restore BG after fasting did not restore NST, nor was NST abolished by intracellular glucoprivation with 2-deoxy-D-glucose in fed rats. Thus, it is not argued that BG concentration is in itself an adequate signal for controlling NST.