Objective—To test the ability of a nested PCR assay to detect Eimeria macusaniensis at various stages of infection in alpacas.
Animals—4 healthy adult alpacas with no detectable E macusaniensis.
Procedures—Alpacas were inoculated with 2 × 104 sporulated oocysts. Serial fecal samples collected during the next 38 days were tested via sucrose flotation and PCR assay.
Results—Oocyst passage was detected via fecal flotation in all 4 alpacas 31 to 35 days after inoculation. Three had positive results for PCR assays on samples obtained 7 to 14 days after inoculation. One alpaca subsequently was removed from the study because of weight loss and inappetence. Two remaining alpacas had positive PCR reactions 28 and 31 days after inoculation, up to 7 days before oocysts appeared in the feces. All fecal samples with positive results for flotation also had positive results for PCR assay.
Conclusions and Clinical Relevance—The PCR assay was able to detect early (7 to 14 days) and late (28 to 31 days) prepatent infection. These positive results suggested that the assay could have been detecting DNA unassociated with oocysts or detecting shedding earlier than has been previously recognized. The gap between the early and late detection periods may not be evident in alpacas receiving a larger or continuous inoculum, as might occur with natural infection. Use of a PCR assay for analysis of fecal samples may be valuable for detection of E macusaniensis during the prepatent period, thus aiding in the identification and control of infected animals.
Objective—To compare numbers of L cells in intestinal samples and blood concentrations of glucagon-like peptide (GLP)-1 between neonatal and mature alpacas.
Sample—Intestinal samples from carcasses of 4 suckling crias and 4 postweaning alpacas for immunohistochemical analysis and blood samples from 32 suckling crias and 19 healthy adult alpacas for an ELISA.
Procedures—Immunohistochemical staining was conducted in accordance with Oregon State University Veterinary Diagnostic Laboratory standard procedures with a rabbit polyclonal anti–GLP-1 primary antibody. Stained cells with staining results in ileal tissue were counted in 20 fields by 2 investigators, and the mean value was calculated. For quantification of GLP-1 concentrations, blood samples were collected into tubes containing a dipeptidyl peptidase-4 inhibitor. Plasma samples were tested in duplicate with a commercial GLP-1 ELISA validated for use in alpacas.
Results—Counts of stained cells (mean ± SD, 50 ± 18 cells) and plasma GLP-1 concentrations (median, 0.086 ng/mL; interquartile range, 0.061 to 0.144 ng/mL) were higher for suckling alpacas than for postsuckling alpacas (stained cells, 26 ± 4 cells; plasma GLP-1 concentration, median, 0.034 ng/mL; interquartile range, 0.015 to 0.048 ng/mL).
Conclusions and Clinical Relevance—Older alpacas had lower numbers of L cells in intestinal tissues and lower blood concentrations of GLP-1 than those in neonates. These findings suggested that there may be a decrease in the contribution of GLP-1 to insulin production in adult alpacas, compared with the contribution in neonates.
To evaluate the level of agreement (LOA) between direct and oscillometric blood pressure (BP) measurements and the ability of oscillometric measurements to accurately detect hypotension in anesthetized chimpanzees (Pan troglodytes).
8 captive, adult chimpanzees.
During prescheduled annual examinations, each chimpanzee underwent general anesthesia and patient monitoring for their examination, echocardiography for a concurrent study, and measurement of direct BP with the use of tibial artery catheterization and oscillometry with the use of a cuff placed around a brachium and a cuff placed around the second digit of the contralateral forelimb for the present study. Bland-Altman plots were generated to compare results for direct and oscillometric BP measurements. Mean bias and 95% LOAs were calculated for oscillometric measurements of systolic arterial pressure (SAP), diastolic arterial pressure (DAP), and mean arterial pressure (MAP) for each cuff site. Sensitivity and specificity in detecting hypotension were also determined for each cuff site.
There were 74 paired direct and brachial oscillometric measurements of each, SAP, MAP, and DAP and 66 paired direct and digit oscillometric measurements of each, SAP, MAP, and DAP. Only brachial oscillometric measurements of MAP had adequate sensitivity (78%) and specificity (95%) to accurately detect hypotension, and this technique also had the least mean bias (0.8 mm Hg; 95% LOA, –29 to 31 mm Hg).
CONCLUSIONS AND CLINICAL RELEVANCE
Results indicated that brachial oscillometric measurement of MAP provided reasonable agreement with tibial arterial direct MAP measurement and performed well in diagnosing hypotension in anesthetized chimpanzees.
Objectives—To determine whether feed restriction
induces hepatic lipidosis (HL) in llamas and to evaluate
the metabolic changes that develop during feed
Animals—8 healthy adult female llamas.
Procedure—Llamas were fed grass hay at a rate of
0.25% of their body weight per day for 13 to 28 days.
Llamas were monitored by use of clinical observation,
serum biochemical analyses, and ultrasound-guided
Results—All 8 llamas lost weight and mobilized fat.
Five llamas developed HL, including 4 that were nursing
crias. During the period of feed restriction, mean
serum concentration of bile acids and activities of
aspartate aminotransferase (AST), sorbitol dehydrogenase
(SDH), and γ-glutamyl transferase (GGT) were
significantly higher in llamas that developed HL, compared
with llamas that did not. Mean insulin-to-cortisol
concentration ratios were lower in llamas with HL
before and up to 7 days of feed restriction, compared
with those that did not develop HL.
Conclusions and Clinical Relevance—HL in llamas
may be induced by severe feed restriction, particularly
in the face of increased energy demand. Llamas
with weight loss attributable to inadequate dietary
intake may develop biochemical evidence of
hepatopathy and HL. Increases in serum concentration
of bile acids and activities of GGT, AST, and SDH
may indicate the development of HL in llamas and
identify affected animals for aggressive therapeutic
intervention. (Am J Vet Res 2001;62:1081–1087)
Objective—To determine blood glucose clearance in
2 species of New World camelids after IV challenge
and to examine mechanisms of this clearance.
Animals—5 adult female llamas and 5 adult gelded
Procedure—After food was withheld for 12 hours,
camelids received 0.5 g of glucose/kg of body weight
by rapid IV infusion. Serum concentrations of glucose,
nonesterified fatty acids, cortisol, and insulin, and
plasma concentrations of lactate were determined
before and 0, 1, 2, 3, 4, 5, 15, 30, 60, 90, 120, 180,
and 240 minutes after infusion. Ratios of insulin to
glucose and insulin to cortisol were calculated for
each time point.
Results—Postinfusion glucose concentrations were
significantly higher in llamas than alpacas for the first
15 minutes and remained significantly higher than
baseline values in both species for 180 minutes.
Lactate and cortisol concentrations did not change
significantly; nonesterified fatty acid concentrations
decreased in both species 30 minutes after infusion.
Baseline insulin concentrations were < 6 μU/ml in
both species and increased only to 10.1 ± 0.7 μU/ml
in llamas. Insulin concentrations did not change significantly
Conclusions and Clinical Relevance—Llamas and
alpacas clear glucose more slowly than other domestic
species after challenge, mainly because of a weak
insulin response and slow cellular uptake. This
response may impair the assimilation of exogenous
glucose as well as make llamas and alpacas prone to
diabetes-like disorders when an abundance of
endogenous or exogenous glucogenic agents are present.
(Am J Vet Res2001;62:682–686)
Objectives—To test whether generalized Streptococcus
zooepidemicus infection could be induced
by intratracheal inoculation in llamas and to characterize
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
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 µg/ml) and increases
in serum glucose (from 131 ± 5 to 253 ± 48 mg/dl)
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. (Am J Vet Res 2000:61;1525–1529)
OBJECTIVE To investigate use of the plethysmographic variability index (PVI) and perfusion index (PI) for evaluating changes in arterial blood pressure in anesthetized tigers (Panthera tigris).
ANIMALS 8 adult tigers.
PROCEDURES Each tiger was anesthetized once with a combination of ketamine, midazolam, medetomidine, and isoflurane. Anesthetic monitoring included assessment of PI, PVI, direct blood pressure measurements, anesthetic gas concentrations, esophageal temperature, and results of capnography and ECG. Mean arterial blood pressure (MAP) was maintained for at least 20 minutes at each of the following blood pressure conditions: hypotensive (MAP = 50 ± 5 mm Hg), normotensive (MAP = 70 ± 5 mm Hg), and hypertensive (MAP = 90 ± 5 mm Hg). Arterial blood gas analysis was performed at the beginning of anesthesia and at each blood pressure condition.
RESULTS Mean ± SD PI values were 1.82 ± 2.38%, 1.17 ± 0.77%, and 1.71 ± 1.51% and mean PVI values were 16.00 ± 5.07%, 10.44 ± 3.55%, and 8.17 ± 3.49% for hypotensive, normotensive, and hypertensive conditions, respectively. The PI values did not differ significantly among blood pressure conditions. The PVI value for the hypotensive condition differed significantly from values for the normotensive and hypertensive conditions. The PVI values were significantly correlated with MAP (r = −0.657). The OR of hypotension to nonhypotension for PVI values ≥ 18% was 43.6.
CONCLUSIONS AND CLINICAL RELEVANCE PVI was a clinically applicable variable determined by use of noninvasive methods in anesthetized tigers. Values of PVI ≥ 18% may indicate hypotension.
To evaluate and compare postoperative analgesic effects of grapiprant and carprofen in dogs undergoing ovariohysterectomy.
42 sexually intact female healthy dogs (< 35 kg and 0.5 to 7 years old) were enrolled.
In a masked, randomized, noninferiority clinical trial, dogs received either 2 mg/kg of grapiprant or 4.4 mg/kg of carprofen orally 2 hours prior to ovariohysterectomy. Postoperative pain was assessed using the Glasgow Composite Pain Scale–Short Form (GCPS-SF) at extubation and 2, 4, 6, 8, 18, and 24 hours postextubation and compared to baseline. After each pain scoring, mechanical nociceptive testing with von Frey monofilaments (vF) was performed to assess hyperalgesia. Hydromorphone (0.05 mg/kg, IM) was administered to any dog with a GCPS-SF of ≥ 5/24. The noninferiority limit (NI) for the GCPS-SF was Δ = 3. The NI for vF was Δ = –0.2. Following noninferiority, a mixed-effect ANOVA and post hoc comparisons were made with the Tukey correction method (P < .05).
3 dogs required rescue analgesia and were excluded from statistical analysis. Of the remaining 39 dogs, the upper CI for GCPS-SF was below the NI of 3 and the lower CI for vF was greater than the NI of –0.2, indicating noninferiority of grapiprant as compared to carprofen. There was no difference between treatment (P = .89) nor treatment by time (P = .62) for GCPS-SF. There was no difference between groups at any time point or over time when vF were used.
Our study results support the use of grapiprant as an analgesic alternative to carprofen in dogs undergoing ovariohysterectomy.
Objective—To determine clinical status and renal and hematopoietic function after kidney donation and identify risks associated with kidney donation in dogs.
Animals—14 dogs that underwent unilateral nephrectomy for kidney donation.
Procedures—Records were reviewed retrospectively to collect data regarding prenephrectomy clinicopathologic variables. Dogs were reexamined prospectively at various times after nephrectomy, and pre- and postnephrectomy CBC, serum biochemical analyses, urinalysis, and urine protein-to-urine creatinine ratio were compared. Six dogs had postnephrectomy renal volume determined ultrasonographically, and 4 of those dogs also underwent scintigraphic determination of glomerular filtration rate and renal biopsy.
Results—All dogs were clinically normal at the time of reevaluation. There were no significant differences between prenephrectomy and postnephrectomy values for BUN concentration or urine specific gravity. Mean postnephrectomy serum creatinine concentration was significantly greater than prenephrectomy concentration. Mean serum phosphorus concentration was significantly decreased after nephrectomy, and mean Hct, corpuscular volume, and corpuscular hemoglobin concentration were significantly increased after nephrectomy. Postnephrectomy renal volume was greatest in dogs < 12 months old at the time of surgery. Mean postnephrectomy glomerular filtration rate was 2.82 ± 1.12 mL/kg/ min (1.28 ± 0.51 mL/lb/min). Renal biopsy specimens obtained during and after nephrectomy were histologically normal.
Conclusions and Clinical Relevance—Renal and hematopoietic variables were within reference ranges in dogs examined up to 2.5 years after unilateral nephrectomy. Compensatory renal hypertrophy was greatest in dogs < 1 year of age at donation. Donor age, along with histocompatability, may be an important factor in selecting dogs for kidney donation.