Pathogenesis of Streptococcus zooepidemicus infection after intratracheal inoculation in llamas.

OBJECTIVES: To test whether generalized Streptococcus zooepidemicus infection could be induced by intratracheal inoculation in llamas and to characterize this infection. ANIMALS: 6 test and 3 control llamas. PROCEDURE: Test llamas received 1 of 3 dosages of S. zooepidemicus by intratracheal injection, whereas control llamas received sterile culture medium. Physical examination variables and results of clinicopathologic analyses of blood, peritoneal fluid, and tracheal wash fluid were compared in test llamas between, before, and during the development of bacteremia and with control llamas. Bacteriologic culture was performed on all collected body fluids and tissue specimens that were collected at necropsy. Tissue specimens that were collected at necropsy were examined histologically. RESULTS: Infection induced fever, anorexia, and signs of depression. Five of 6 infected llamas developed specific signs of inflammation in the thorax or abdomen, bacteremia, neutrophilic leukocytosis with toxic changes and high band neutrophil cell counts, hyperfibrinogenemia, and high peritoneal fluid WBC counts and protein concentrations. On development of bacteremia, llamas had significant decreases in serum iron (from 118+/-25 to 6+/-4 microg/ml) and increases in serum glucose (from 131+/-5 to 253+/-48 mg/dl) concentrations. CONCLUSIONS AND CLINICAL RELEVANCE: Streptococcus zooepidemicus spreads rapidly to other body compartments after intratracheal inoculation in llamas. Fever, anorexia, and signs of depression are the most consistent clinical signs, although other signs are possible. Clinicopathologic analysis of body fluids yields evidence of inflammation. Infection by S. zooepidemicus can be proven by bacteriologic culture of body fluids before death or of tissue specimens after death.

Congenital joint laxity and disproportionate dwarfism in a herd of beef cattle.

Three calves from a herd of beef cattle were examined because of disproportionate dwarfism and excessive extension of metacarpophalangeal and metatarsophalangeal joints. Abnormalities had been noticed at birth, 1 to 6 days earlier. A thorough herd investigation revealed that 16 calves born to 70 multiparous cows were affected during the calving season. The condition did not adversely affect calf survival. Affected calves had limbs that were disproportionally short, compared with their trunk size, and wide epiphyses of the femurs and humeri. Radiographic evaluation revealed incomplete maturation of carpal and tarsal bones and incomplete maturation and abnormal flaring of epiphyses of the short humeri and femurs. Histologic findings were consistent with chondrodystrophy. This disorder had not been seen in the herd in previous years and was traced to feeding of dry, spoiled silage to the dams during midgestation. Covering the silage prevented problems in the subsequent year.

Treatment of neonatal calf diarrhea with an oral electrolyte solution supplemented with psyllium mucilloid.

Dairy calves under 14 days of age with naturally occurring, uncomplicated diarrhea were treated for 3 days with a hypertonic oral electrolyte solution with (n = 15) or without (n = 12) psyllium. Clinical response and clinical pathology data were compared between the 2 groups. Glucose absorption was evaluated on days 1 and 3 by measurement of plasma glucose and lactate and serum insulin concentrations for 4 hours after formula administration. On day 1, glucose, lactate, and insulin concentrations were lower in psyllium-fed calves than in control calves, with significant differences noted in glucose and lactate concentrations at several time points (P < 0.05). Plasma lactate concentrations were higher at several times in both treatment groups on day 3 than on day 1 (P < 0.05). Fecal consistency was markedly different in psyllium-fed calves as compared with control calves within 24 hours of psyllium supplementation. Fecal percent dry matter content was lower in psyllium-fed calves than in control calves at least once a day during supplementation and on day 3 compared with day 0 in the psyllium-fed calves (P < 0.05). There were no significant differences in clinical performance scores, hydration status, arterial blood gas, serum anion gap, electrolyte, or total CO2 concentrations. Addition of psyllium to an oral electrolyte solution resulted in immediate alterations in glucose absorption without impairing rehydration in diarrheic calves, but differences were transient and did not affect clinical outcome.

Atrioventricular septal defects in three llamas (Lama glama).

Two half-sibling neonatal llamas (Lama glama) and one unrelated adult llama were presented with various complaints, including failure to thrive, respiratory distress, and excessive recumbency. The related camelids were born in successive years to the same dam but from unrelated sires. Thoracic auscultation revealed significant systolic and diastolic murmurs on both sides of the chest in all three llamas, and arterial blood gas evaluation revealed hypoxemia in two llamas. Echocardiographic examinations revealed large atrioventricular septal (AVS) defects in all three llamas. Two llamas were euthanized after diagnosis and the third died 4 mo later. Postmortem examination confirmed large AVS defects in all animals. There also was marked cardiomegaly in each animal. The discovery of such a cardiac anomaly in these three camelids suggests that it may be common in this species and may have a genetic basis.

Acute gastrointestinal disease in 27 New World camelids: clinical and surgical findings.

OBJECTIVE: To describe clinical and surgical findings from New World camelids with acute gastrointestinal disease. STUDY DESIGN: Retrospective study. ANIMAL POPULATION: 20 llamas and 7 alpacas. METHODS: Camelids were grouped based on surgical lesions. Clinical and surgical findings were compared between groups and between surviving and nonsurviving camelids. RESULTS: Twelve of 27 initial celiotomies and 3 of 4 repeat celiotomies were successful. Death occurred from euthanasia during surgery (nine camelids), peritonitis or sepsis (five), aspiration pneumonia (one), and respiratory distress (one). Survival was lowest after celiotomy for proximal obstruction (3 of 10 camelids), ruptured viscus (0 of 4), and necrotizing enteritis (0 of 2) and highest after celiotomy for distal obstruction (10 of 13) and septic peritonitis without ruptured viscus (2 of 2). Before surgery, camelids with proximal obstruction had significantly lower (P < .05) serum chloride concentrations (median, 97 mEq/L) than those with distal obstruction (median, 109 mEq/L) or ruptured viscus (median, 117 mEq/L). Serum bicarbonate concentration also was highest (median, 34.6 mEq/L) and often greater than 28 mEq/L in camelids with proximal obstruction. Camelids with distal obstruction had significantly lower (P < .05) nucleated cell counts in peritoneal fluid (median, 700 cells/microL) than those with ruptured viscus (median, 20,600 cells/microL) or septic peritonitis (median, 88,300 cells/microL). CONCLUSIONS: Camelids with proximal obstruction often had hypochloremic metabolic alkalosis. Camelids with distal obstruction had less metabolic derangement and tissue compromise and a higher survival rate. CLINICAL RELEVANCE: Awareness of the characteristics of the various types of acute gastrointestinal disease in camelids will augment veterinarians' ability to diagnose and treat these disorders.

Idiopathic eosinophilic enteritis in four cattle.

Four cattle had chronic diarrhea and had lost weight but were not anorectic or dehydrated. A diagnosis of eosinophillic enteritis was made on the basis of a combination of clinical and histopathologic findings and exclusion of other diseases. Eosinophilia and hypoalbuminemia were not detected in CBC analyses. Gross and histologic examination of the small intestine revealed edema, diffuse eosinophilic inflammation (> 20 eosinophils/HPF [400 x]), and regional lymphadenopathy. A causative agent was not identified in any of the cattle. Treatment consisting of a 1-month course of systemically administered corticosteroids was attempted in 2 cattle and was apparently successful in both. Diagnostic criteria for eosinophilic enteritis have not been established for cattle and, therefore, the diagnosis was subjective. This disease resembled paratuberculosis (Johne's disease) in clinical appearance but was distinguished on the basis of a lack of a contagious etiologic agent and differences in histologic appearance.

Surgical and nonsurgical correction of uterine torsion in New World camelids: 20 cases (1990-1996).

OBJECTIVE: To report clinical findings for New World comelids with uterine torsion and to compare results of 3 methods of correction. DESIGN: Retrospective case series. ANIMALS: 11 llamas and 3 alpacas with 20 uterine torsions. PROCEDURE: Information concerning history, clinical signs, management, and postpartum complications was retrieved from medical records. Information concerning subsequent reproductive performance was obtained by telephone interview of owners. RESULTS: Uterine torsion was corrected by celiotomy (n = 7); transvaginal manipulation (5), or rolling the dam (8). Direction of 19 of 20 torsions was clockwise when viewed from the rear. Retention of fetal membranes was reported for 5 camelids that underwent celiotomy, but was not reported in camelids after nonsurgical correction. The uterus prolapsed in 1 llama that underwent celiotomy and in another that underwent the rolling technique. Although 2 camelids that underwent celiotomy subsequently failed to conceive, all camelids treated by nonsurgical techniques conceived. CLINICAL IMPLICATIONS: Uterine torsion in camelids may be diagnosed by methods similar to those used in cattle. Surgical and nonsurgical methods can be used to correct torsion, and postpartum complications are rare when torsion is corrected by a nonsurgical method.

Gravel obstruction in the abomasum or duodenum of two cows.

Two Holstein cows from dry lot dairies were evaluated because of clinical signs of depression, anorexia, and decreased milk production. Bilateral abdominal distention and decreased fecal output were found on physical examination. Results of serum biochemical analyses indicated that the cows had severe hypochloremic, hypokalemic metabolic alkalosis. On the basis of physical examination and laboratory findings, an obstruction of the abomasum or cranial portion of the small intestine was suspected in these cows and abdominal exploratory surgery was performed. A mass of gravel was found in the pyloric antrum of the abomasum of 1 cow and the descending duodenum of the other cow. The duodenal obstruction was removed by enterotomy, and the pyloric mass was manually reduced during surgery. The cows were treated with antibiotics and isotonic saline solution (NaCl) supplemented with potassium chloride and recovered quickly after surgery.

Tooth root abscesses in New World camelids: 23 cases (1972-1994).

OBJECTIVE: To determine typical clinical and radiographic findings in a group of New World camelids with tooth root abscesses and to determine outcome after medical and surgical treatment. DESIGN: Retrospective case series. ANIMALS: 23 llamas and alpacas with radiographic and clinical evidence of tooth root abscesses. PROCEDURE: Disease history, signalment, physical and radiographic examination findings, bacteriologic culture results, treatment, and short-term and long-term outcome were retrieved from the medical records. RESULTS: Local swelling was the most common clinical abnormality in camelids with tooth root abscesses. Mandibular molars were affected most commonly, and bacteriologic culture of samples from lesions often revealed facultative anaerobic bacteria. Antibiotic treatment for at least 30 days, surgical extraction of the affected tooth, and a root canal procedure were used successfully to treat tooth root abscesses. CLINICAL IMPLICATIONS: Both surgical and medical treatment of tooth root abscesses may lead to successful resolution of clinical signs in New World camelids.

Forestomach acidosis in six New World camelids.

Forestomach acidosis was diagnosed in 2 llamas and 4 alpacas. All were young, group-housed, sexually intact males. Clinical signs included forestomach atony, lethargy, ataxia, diarrhea, and tachycardia. Forestomach distention was observed in only 1 llama. Clinicopathologic abnormalities included low forestomach fluid pH, hyperchloremia, hypokalemia, and metabolic acidosis. Although camelids differ from domestic ruminants in typical management practices and behavioral, anatomic, and physiologic characteristics, they are, nonetheless, susceptible to forestomach acidosis. Gastric fluid analysis was essential for an accurate diagnosis. Four of 6 camelids recovered after PO and IV treatment with alkalinizing agents and fluids, antibiotics, and thiamine.