Objective—To evaluate molecular and histologic characteristics of the superficial digital flexor tendon (SDFT), deep digital flexor tendon (DDFT), and suspensory ligament (SL) and assess trace-mineral concentrations in serum, liver, and hair of juvenile llamas with metacarpophalangeal and metatarsophalangeal joint hyperextension.
Animals—12 juvenile llamas (6 with bilateral hyperextension of metacarpophalangeal joints, metatarsophalangeal joints, or both and 6 clinically normal control llamas).
Procedures—Radiography and ultrasonography of metacarpophalangeal and metatarsophalangeal regions were performed. Llamas were euthanized, and SDFT, DDFT, and SL samples were collected for histologic evaluation of collagen and elastin content and orientation, proteoglycan content, and collagen type III immunohistochemistry. Total RNA was isolated from SL tissue, and gene expression of collagen types I and III, lysyl oxidase, and matrix metalloproteinase-13 was evaluated via real-time quantitative reverse transcriptase PCR assay. Liver, serum, and hair samples were evaluated for trace mineral content.
Results—Collagen type III gene expression and proteoglycan content were significantly increased in SL samples of affected juvenile llamas, compared with those of control llamas. No difference was detected in collagen and elastin content and orientation or in gene expression of collagen type I, lysyl oxidase, or matrix metalloproteinase-13 between groups. Affected llamas had significantly increased serum molybdenum and decreased liver cobalt concentrations, compared with values for control llamas.
Conclusions and Clinical Relevance—Increased collagen type III gene expression and proteoglycan content in SL samples of affected juvenile llamas provided evidence of ongoing SL matrix repair. Trace mineral differences may have been attributable to dietary imbalances in affected llamas.
Objective—To determine the molecular and histologic characteristics of hyperextension of the metacarpophalangeal and metatarsophalangeal joints in adult llamas.
Animals—12 adult llamas (6 with bilateral hyperextension of the metacarpophalangeal or metatarsophalangeal joints [affected] and 6 age- and sex-matched clinically normal control llamas).
Procedures—Llamas were euthanized, and specimens of superficial digital flexor tendon, deep digital flexor tendon, and suspensory ligament were obtained from 4 areas and snap frozen in liquid nitrogen or suspended in neutral-buffered 10% formalin. Histologic evaluation of collagen fiber orientation, elastin content, and proteoglycan content was performed by use of Masson trichrome, picrosirius red, Verhoeff, and Alcian blue stains. Total RNA was isolated from frozen suspensory ligament specimens. Gene expression of collagen types I and III, lysyl oxidase, and matrix metalloproteinase-13 was evaluated with a real-time quantitative reverse transcriptase PCR assay.
Results—Gene expression of collagen types I and III, lysyl oxidase, and matrix metalloproteinase-13 in suspensory ligaments was similar between affected and control llamas. Collagen orientation and elastin content of the flexor tendons and suspensory ligaments were also similar between the groups. Proteoglycan content was low in most specimens but was focally increased in discrete lesions of suspensory ligaments in 2 affected and 2 control llamas.
Conclusions and Clinical Relevance—Hyperextension of the metacarpophalangeal or metatarsophalangeal joints in llamas did not appear to be caused by degeneration or inflammation of the suspensory ligament. Although focal proteoglycan accumulation existed in the suspensory ligaments of 2 affected llamas, widespread abnormal connective tissue proteoglycan accumulation was not found.
Objective—To determine the morphologic and biochemical characteristics of hyperextension of the metacarpophalangeal and metatarsophalangeal joints in llamas.
Animals—12 adult llamas (6 with bilateral hyperextension of the metacarpophalangeal or metatarsophalangeal joints and 6 age- and sex-matched control llamas).
Procedures—Llamas were evaluated by use of lameness examination, ultrasonography, and radiography. A CBC, serum biochemical analysis, and determination of concentrations of trace minerals in serum and liver samples were performed. Llamas were euthanized, and samples of the superficial digital flexor tendon, deep digital flexor tendon, and suspensory ligament were obtained from 4 areas and snap-frozen in liquid nitrogen or suspended in neutral-buffered 10% formalin. Immunohistochemical evaluation of collagen types I and III and assays for measurement of lysyl oxidase activity were performed.
Results—2 affected llamas had a visible gait deficit associated with metacarpophalangeal joint hyperextension. Radiographic evidence of osteoarthritis was detected in 1 severely affected llama, and ultrasonographic changes of soft tissue mineralization and suspensory desmitis were observed in 2 llamas. Liver concentrations of copper were lower and serum concentrations of zinc higher in affected llamas, compared with values in control llamas. Lysyl oxidase activity and collagen distribution did not differ significantly between groups.
Conclusions and Clinical Relevance—Hyperextension of the metacarpophalangeal or metatarsophalangeal joints in llamas does not appear to be the result of injury or degeneration of the suspensory ligament or flexor tendons. Lower copper concentrations coupled with higher zinc concentrations in affected llamas may be indicative of secondary copper deficiency.
Objective—To assess effects of treatment with phenylbutazone (PBZ) or a combination of PBZ and flunixin meglumine in horses.
Animals—24 adult horses.
Procedure—13 horses received nonsteroidal antiinflammatory drugs (NSAIDs) in a crossover design. Eleven control horses were exposed to similar environmental conditions. Treated horses received PBZ (2.2 mg/kg, PO, q 12 h, for 5 days) and a combination of PBZ and flunixin meglumine (PBZ, 2.2 mg/kg, PO, q 12 h, for 5 days; flunixin meglumine, 1.1 mg/kg, IV, q 12 h, for 5 days). Serum samples were obtained on day 0 (first day of treatment) and day 5, and total protein, albumin, and globulin were measured.
Results—1 horse was euthanatized with severe hypoproteinemia, hypoalbuminemia, and colitis during the combination treatment. Comparisons revealed no significant difference between control horses and horses treated with PBZ alone. There was a significant difference between control and treated horses when administered a combination of PBZ and flunixin meglumine. Correction for horses with values >2 SDs from the mean revealed a significant difference between control horses and horses administered the combination treatment, between control horses and horses administered PBZ alone, and between horses receiving the combination treatment and PBZ alone. Gastroscopy of 4 horses revealed substantial gastric ulcers when receiving the combination NSAID treatment.
Conclusions and Clinical Relevance—Analysis of results of the study indicates the need for caution when administering a combination NSAID treatment to horses because the detrimental effects may outweigh any potential benefits.
Objective—To describe a technique for abdominocentesis in camelids and report peritoneal fluid biochemical and cytologic findings from healthy llamas and alpacas.
Animals—17 adult llamas and 5 adult alpacas.
Procedures—Right paracostal abdominocentesis was performed. Peritoneal fluid was collected by gravity flow into tubes containing potassium-EDTA for cell count and cytologic evaluation and lithium heparin for biochemical analysis. Blood samples were collected via jugular venipuncture into heparinized tubes at the same time. Cytologic components were quantified. Fluid pH and concentrations of total carbon dioxide, sodium, potassium, chloride, lactate, and glucose were compared between peritoneal fluid and venous blood.
Results—All but 3 camelids had peritoneal fluid cell counts of < 3,000 nucleated cells/μL, with < 2,000 neutrophils/μL and < 1,040 large mononuclear cells/μL. All but 1 had peritoneal fluid protein concentrations of ≥ 2.5 g/dL. Peritoneal fluid of camelids generally contained slightly less glucose, lactate, and sodium and roughly equal concentrations of potassium and chloride as venous blood.
Conclusions and Clinical Relevance—Peritoneal fluid was collected safely from healthy camelids. Compared with blood, peritoneal fluid usually had a low cell count and protein concentration, but some individuals had higher values. Electrolyte concentrations resembled those found in blood. High cell counts and protein concentrations found in peritoneal fluid of some healthy camelids may overlap with values found in diseased camelids, complicating interpretation of peritoneal fluid values.
Objective—To characterize serum trace mineral, sex steroid hormone, and vitamin D concentrations and identify factors associated with metacarpophalangeal and metatarsophalangeal hyperextension in llamas and alpacas.
Samples—Serum samples from 79 llamas and 15 alpacas and owner survey data for 573 llamas and 399 alpacas.
Procedures—Serum samples were stored at −20°C until analysis and were evaluated for trace mineral, vitamin D, estradiol, progesterone, and testosterone concentrations. Information regarding age of onset, number of affected animals in herd, feed and supplements given, type of housing, and management practices was obtained in an owner survey.
Results—Higher serum zinc and iron concentrations were associated with metacarpophalangeal and metatarsophalangeal hyperextension in camelids, compared with controls. In summer and fall months, vitamin D concentrations were significantly higher in affected camelids than controls. Overall prevalence was 13.3% in llamas, compared with 0.7% in alpacas. No management factors were found to be predictive of this condition. No other factors examined were associated with metacarpophalangeal and metatarsophalangeal hyperextension.
Conclusions and Clinical Relevance—Despite similar supplementation practices and environmental conditions between affected and unaffected animals, an association of high serum zinc, iron, and vitamin D concentrations in affected camelids, compared with controls, may indicate differences of intake or absorption of dietary supplements.
Case Description—A 5-year-old castrated male Vietnamese pot-bellied pig (Sus scrofa) was evaluated because of anorexia, vomiting, diarrhea, and weight loss.
Clinical Findings—Hypermotile gastrointestinal sounds were noted on abdominal auscultation. An inflammatory leukogram, dehydration, prerenal azotemia, hyponatremia, hypochloremia, hyperproteinemia, hyperglobulinemia, hypomagnesemia, and high γ-glutamyl transpeptidase activity were identified. Transabdominal ultrasonography revealed distended loops of small intestine.
Treatment—IV fluid therapy and analgesic treatment were unsuccessful in the resolution of clinical signs. Exploratory laparotomy revealed an ileocecal intussusception involving the distal portion of the ileum. Distal ileal and cecal bypass were achieved via side-to-side anastomosis of the proximal portion of the ileum and spiral colon with a gastrointestinal anastomosis stapler. Ileal transection or occlusion was not performed. Postoperative complications were minimal, and the pig was clinically normal 15 months after surgery and required no special care or diet.
Clinical Relevance—Distal ileal and cecal bypass without ileal transection have not been described previously in Vietnamese pot-bellied pigs. Anastomosis of the proximal portion of the ileum to the spiral colon without major complications represents a novel, technically simple approach to bypass of the distal portion of the ileum and cecum.
A 2-month-old 12.0-kg (26.4-lb) sexually intact male alpaca was evaluated for a 1-week history of progressive forelimb lameness with no known history of trauma.
The cria had toe-touching lameness in the right forelimb with a firm swelling at the distal dorsomedial metacarpal region. Signs of pain were elicited on palpation of the swollen region. There was no associated wound or draining tract. Radiographic examination revealed soft tissue swelling and osteomyelitis of the distal portion of the third metacarpal bone with a possible medial cortical sequestrum.
TREATMENT AND OUTCOME
The cria was hospitalized and treated with meloxicam (1 mg/kg [0.45 mg/lb], PO, q 72 h) and ceftiofur sodium administered SC (2.2 mg/kg [1 mg/lb], q 12 h for 8 days) and by means of regional limb perfusion (1.25 mg/kg [0.57 mg/lb], IV, q 48 h for 8 days). Lameness and swelling improved, and the cria was discharged from the hospital with meloxicam (1 mg/kg, PO, q 72 h for 2 weeks) and ceftiofur crystalline free acid (1.5 mg/kg [0.68 mg/kg], SC, q 5 d for 2 weeks). At a recheck examination 17 days later, there was radiographic evidence of a well-defined 3.4 × 0.3-cm osseous sequestrum in the distal aspect of the affected third metacarpal bone. The owner declined further treatment and elected to monitor the cria at home. One year later, radiographic examination revealed nearly complete resolution of the sequestrum.
Results for this patient suggested that osseous sequestra in some camelids may resolve following medical treatment without surgical intervention.
Objective—To determine the effectiveness of administering multiple doses of phenylbutazone alone or a combination of phenylbutazone and flunixin meglumine to alleviate lameness in horses.
Animals—29 adult horses with naturally occurring forelimb and hind limb lameness.
Procedures—Lameness evaluations were performed by use of kinematic evaluation while horses were trotting on a treadmill. Lameness evaluations were performed before and 12 hours after administration of 2 nonsteroidal anti-inflammatory drug (NSAID) treatment regimens. Phenylbutazone paste was administered at approximately 2.2 mg/kg, PO, every 12 hours for 5 days, or phenylbutazone paste was administered at approximately 2.2 mg/kg, PO, every 12 hours for 5 days in combination with flunixin meglumine administered at 1.1 mg/kg, IV, every 12 hours for 5 days.
Results—Alleviation of lameness was greater after administration of the combination of NSAIDs than after oral administration of phenylbutazone alone. Improvement in horses after a combination of NSAIDs did not completely mask lameness. Five horses did not improve after either NSAID treatment regimen. All posttreatment plasma concentrations of NSAIDs were less than those currently allowed by the United States Equestrian Federation Inc for a single NSAID. One horse administered the combination NSAID regimen died of acute necrotizing colitis during the study.
Conclusions and Clinical Relevance—Administration of a combination of NSAIDs at the dosages and intervals used in the study reported here alleviated the lameness condition more effectively than did oral administration of phenylbutazone alone. This may attract use of combinations of NSAIDs to increase performance despite potential toxic adverse effects.
To compare results for initial body-mounted inertial sensor (BMIS) measurement of lameness in equids trotting in a straight line with definitive findings after full lameness evaluation.
Lameness measured with BMIS equipment while trotting in a straight line was classified into categories of none, forelimb only, hind limb only, and 8 patterns of combined forelimb and hind limb lameness (CFHL). Definitive findings after full lameness evaluation were established in most horses and classified into types (no lameness, forelimb- or hind limb–only lameness, CFHL, or lameness not localized to the limbs). Observed proportions of lameness type in equids with definitive findings for each initial BMIS-assessed category were compared with hypothetical expected proportions through χ2 goodness-of-fit analysis.
The most common initial BMIS-assessed lameness category was CFHL (693/1,224 [56.6%]), but this was the least common definitive finding (94/ 862 [10.9%]). The observed frequency of no lameness after full lameness evaluation was greater than expected only when initial BMIS measurements indicated no lameness. The observed frequency of forelimb-only lameness was greater than expected when initially measured as forelimb-only lameness and for CFHL categories consistent with the diagonal movement principle of compensatory lameness. Observed frequency of hind limb–only lameness was greater than expected when initially measured as hind limb–only lameness and for CFHL categories consistent with the sagittal movement principle of compensatory lameness. Equids initially assessed as having no lameness had the highest (103/112 [92%]) and those assessed as CFHL pattern 7 (forelimb with contralateral hind limb impact-only lameness) had the lowest (36/66 [55%]) rates of definitive findings.
CONCLUSIONS AND CLINICAL RELEVANCE
In equids, results of initial straight-line trotting evaluations with a BMIS system did not necessarily match definitive findings but may be useful in planning the remaining lameness evaluation.