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in Journal of the American Veterinary Medical Association

SUMMARY

Five castrated male llamas (mean body weight, 94 kg) were studied in an energy balance trial to determine maintenance energy requirement of llamas. Llamas were fed a 50% oat hay-50% pelleted concentrate diet (2.43 Mcal of metabolizable energy/kg of diet dry matter) at approximately 1.6% of body weight (bw). An 8-day total collection digestion trial was used to determine fecal and urine energy losses. Heat production and methane emissions were determined via indirect respiration calorimetry-measurements on each llama fed at the same level of intake as during the digestion trial and subsequently on days 3 and 4 of a period of nonfeeding. Fecal, urine, and methane energy losses of the llamas fed near-maintenance intake were 32.5, 3.5, and 7.1% of gross energy intake, respectively. The postabsorptive metabolic rate, commonly called nonfed (fasting) heat production, was 59.3 kcal/bw 0.75. Using a linear relation between postabsorptive and maintenance energy requirement and efficiency of energy use below maintenance of 0.702, metabolizable energy requirement at maintenance was determined to be 84.5 kcal/bw 0.75.

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in American Journal of Veterinary Research

Objective

To report clinical findings for New World camelids 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. (J Am Vet Med Assoc 1997;211:600–602)

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in Journal of the American Veterinary Medical Association

Abstract

Objective

To develop appropriate reference ranges for plasma IgG concentrations of llamas.

Animals

643 llamas on 5 farms.

Procedure

Plasma IgG concentration was measured by using a single radial immunodiffusion assay kit. Farm of origin, age, body condition score, and sex were recorded for each llama. The effect of each factor on plasma IgG concentration was evaluated separately, using ANOVA; the association between age and IgG concentration was evaluated, using linear regression. Multivariable regression models were developed to examine concurrent effects of age, sex, body condition score, farm, and various interactions on IgG concentration.

Results

The IgG concentrations were between 127 and 3,969 mg/dl. In llamas < 12 months old, farm of origin accounted for 29% of variability for IgG concentration. Reference range for plasma IgG concentrations in llamas < 12 months old was 391 to 2,357 mg/dl; for llamas > 12 but < 28 months old was 771 to 2,796 mg/dl; and for llamas > 28 months old was 570 to 3,264 mg/dl. These ranges were applicable only for the kit used in this study.

Conclusions

Healthy llamas have a wide range of IgG concentrations. Determinants of IgG concentration are multifactorial, and their importance varies with age of the llamas.

Clinical Implications

The wide range of IgG concentrations observed in healthy llamas and the influence that age and farm may have on IgG concentrations indicate that a result for one specific llama should be interpreted in relation to those of its herdmates. (Am J Vet Res 1998;59:406–409)

Free access
in American Journal of Veterinary Research
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association

Summary

Uterine tissue specimens from 90 llamas with history of infertility were examined and graded microscopically; 83 specimens were obtained by endometrial biopsy and 7 specimens were obtained at necropsy. Fifteen llamas (16.7%) had a normal uterus, which was graded 1A. Twenty-three llamas (25.6%) had minor uterine abnormalities that were graded lB. Forty-five llamas (50.0%) had appreciable endometritis that was graded 2A. Three llamas (3.3%) had endometritis with gland fibrosis that was graded 2B. Two llamas (2.2%) had notable uterine gland fibrosis that was graded 3A. Two llamas (2.2%) had uterine neoplasia that was graded 3B. Thirty-six llamas had follow-up evaluation; 22 became pregnant, most after some form of treatment. Uterine biopsy in llamas was readily performed without complications and was valuable in identifying a wide range of uterine diseases, most of which were amenable to treatment.

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in Journal of the American Veterinary Medical Association

SUMMARY

Indices of renal function and damage were measured in 12 healthy male adult llamas fed a diet of mixed alfalfa/grass hay (mixed hay) and water ad libitum. Using a collection bag fitted over the preputial area, urine samples were collected at 6, 12, and 24 hours. Serum samples were obtained concurrently to determine endogenous creatinine clearance (cl), total (te) and fractional excretion (fe) of electrolytes (Na, K, Cl, P), electrolyte cl, urine and serum osmolality, urine enzyme activities (γ-glutamyltransferase and N-acetyl-β-D-glucosaminidase), and urine protein concentration. Urine production was quantified. Three months later, 10 of the 12 llamas were fed a grass hay diet and water ad libitum. Similar samples were obtained, and similar measurements were made.

Urine production was higher when the llamas were fed the mixed hay diet. Total urine volume for llamas fed mixed hay ranged from 628 to 1,760 ml/24 h, with a median of 1,307.5 ml/24 h, compared with a range of 620 to 1,380 ml/24 h and a median of 927.50 ml/24 h for llamas fed grass hay. Median urine osmolality was higher in llamas fed mixed hay (1,906 mOsm/kg of body weight, with a range of 1,237 to 2,529 mOsm/kg), compared with llamas fed grass hay (1,666 mOsm/kg, with a range of 1,163 to 2,044 mOsm/kg). Creatinine cl did not vary significantly over time for either diet. Median creatinine cl was higher for llamas fed mixed hay, compared with llamas fed grass hay-0.78 ml/min/kg, with a range of 0.20 to 1.83 ml/min/kg vs 0.45 ml/min/kg, with a range of 0.13 to 3.17 ml/min/kg. Clearances for K and a varied significantly among the periods. However, median Cl for Na and P did not vary over time for either diet. Overall values for these electrolytes in llamas fed mixed hay and grass hay diets were: cl Na, 0.001 and 0.002 ml/min/kg and cl P, 0.0006 and 0.0004 ml/min/kg, respectively. The FE rates of K, cl, and P did not vary significantly over time for either diet. Median respective FE for these electrolytes in the llamas fed mixed hay and grass hay diets include: fe K, 84.90 and 63.10%; fe Cl, 0.85 and 1.30%; and fe P, 0.10 and 0.10%. Fractional excretion of Na varied over time for both diets and could not be expressed accurately as an overall median. Median respective te of electrolytes for llamas fed the mixed hay and grass hay diets were: te Na, 0.007 and 0.03 mEq/kg/h; te Cl, 0.04 and 0.06 mEq/kg/h; and te P, 0.0002 and 0.00 mg/kg/h; te K varied significantly (P < 0.05) over time for both diets. Urine γ-glutamyltransferase activity changed significantly (P < 0.05) over time. Urine N-acetyl-β-D-glucosaminidase activity was influenced by an interaction between diet and time. Median urine protein concentration was 26.0 mg/dl, with a range of 11.0 to 73.0 mg/dl for llamas fed mixed hay, and was 28.0 mg/dl, with a range of 16.0 to 124.0 mg/dl for Hamas fed grass hay.

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in American Journal of Veterinary Research

Summary

Immunodeficiency was diagnosed as the cause of severe debilitating disease characterized by weight loss, failure to grow, and persistent infections that failed to respond to treatment in 12 young llamas. The llamas were affected after maternal-acquired immunity had decreased; failure of passive transfer of immunoglobulins thus was not suspected. Areas of lymph nodes containing T lymphocytes were hypocellular, suggesting T-cell involvement. High serum immunoglobulin concentrations were not found, despite the existence of infectious disease, suggesting at least secondary B-cell involvement. Results of lymphocyte blastogenesis assays were suggestive of B- and T-cell involvement. It was not possible to determine whether the condition was inherited or acquired.

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in Journal of the American Veterinary Medical Association