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Biomedical subjects

R L Hegstad

Publications and source records attributed to R L Hegstad.

At least 19 recordsLinked to original sources
PubMed1997

Alterations in carbohydrate metabolism in dogs with nonhematopoietic malignancies.

OBJECTIVE: To determine whether alterations in carbohydrate metabolism exist in dogs with nonhematopoietic malignancies but without evidence of weight loss or cachexia. ANIMALS: 90 dogs with nonhematopoietic malignancies and 18 control dogs. PROCEDURE: An intravenous glucose tolerance test was done in 90 dogs with previously untreated nonhematopoietic malignancies and in 18 clinically normal dogs. These dogs also had no evidence of unrelated diseases that would affect glucose metabolism. None of the dogs had evidence of cachexia. Samples were assayed for glucose, lactate, and insulin concentrations. This procedure was repeated for 45 of the tumor-bearing dogs from which all gross evidence of tumor was completely excised and evidence of diseases that would alter carbohydrate metabolism did not exist. RESULTS: The mean of all time points during the intravenous glucose tolerance test (ie, 0, 5, 15, 30, 45, and 60 minutes) for lactate (12.9 +/- 6.7 mg/dl) and insulin (69.1 +/- 44.9 microU/ml) concentrations in untreated dogs with nonhematopoietic malignancies were significantly higher than values for controls (lactate, 9.7 +/- 4.3 mg/dl; and insulin, 31.7 +/- 11.5 microU/ml). This increase in lactate and insulin values did not return to normal when the dogs were rendered free of all observable evidence of cancer after surgery. CONCLUSIONS: Carbohydrate metabolism is altered in dogs with a variety of nonhematopoietic malignancies and these abnormalities do not abate when dogs are rendered free of gross evidence of malignant disease after surgery. CLINICAL RELEVANCE: Alterations in carbohydrate metabolism may result in decreased quality of life and may be associated with the paraneoplastic syndrome, cancer cachexia.

Animals↗
PubMed1996

Benign familial hyperphosphatasemia in Siberian huskies.

OBJECTIVE: To evaluate benign familial hyperphosphatasemia involving serum alkaline phosphatase (SAP) in pups. DESIGN: Pups with markedly increased SAP activity were evaluated and compared with unaffected siblings, and with other unaffected Siberian Husky pups from the same colony. ANIMALS: 8 related litters of Siberian Husky pups (n = 56). PROCEDURE: At ages 11 and 16 weeks, pups were given physical examinations and blood was obtained for hematologic and serum biochemical analyses (including electrolytes and isoenzymes of alkaline phosphatase), ionized calcium concentration, and serum parathyroid hormone concentration. Diet, growth and health performance, skeletal radiographs, and genealogical data also were evaluated. RESULTS: Of 42 pups tested, 17 had markedly high total SAP values. Mean total SAP activity of affected pups at ages 11 and 16 weeks was over 5 times greater than mean total SAP activity of unaffected siblings and other unaffected Siberian Husky pups of the same age (P < 0.001). Clinical, radiologic, and biochemical evaluation of the subjects revealed no other abnormal findings. The source of the increased SAP activity was characterized in 5 affected pups as bone isoenzyme. The mode of inheritance could be deduced from the data, but the trait clearly is familial and autosomal. CONCLUSION: The condition described in the family of Siberian Huskies bears similarity to human benign, persistent, familial hyperphosphatasemia. CLINICAL RELEVANCE: Benign familial hyperphosphatasemia should be considered in the differential diagnosis of markedly increased SAP activity in young dogs.

Alkaline Phosphatase↗
PubMed1995

Bioequivalency comparison between two gonadotropin-releasing hormone products.

The bioequivalency of 2 gondatropin-releasing hormone (GnRH) preparations, gonadorelin diacetate tetrahydrate and gonadorelin semicarbonate, was compared on the basis of luteinizing hormone (LH)-releasing ability of the 2 products in diestrous dairy cows. Twenty-four cycling, nonlactating Holstein cows were subjected to a double prostaglandin estrus synchronization treatment to simultaneously control stage of the estrous cycle and time factors as potential variables effecting LH responses to the treatments being studied. Circulating progesterone concentration was determined to verify stage of cycle at strategic times throughout the study. Twelve days after the second prostaglandin treatment, all cows were randomly assigned to 1 of 2 groups (n = 12). Each group of 12 cows received single doses (100 micrograms) of either GnRH preparation at the start of each test period in a 2-period crossover design. Serum samples were obtained prior to and at 12 times (10, 20, 30, 45, 60, 90, 120, 180, 240, 360, 480, and 1,440 minutes) after treatment and were assayed to determine circulating LH concentration. Significant difference between the 2 GnRH products was not found with respect to: mean concentration of LH in the blood during the 24 hours after treatment; maximal LH concentration; time from treatment to maximal LH concentration; and area under the LH concentration curve from time 0 through each of 7 times after treatment (0.5, 1, 1.5, 2, 4, 8, and 24 hours). These data confirm the bioequivalency of the 2 GnRH products.

Animals↗
PubMed1995

Evaluation of pulmonary function and analgesia in dogs after intercostal thoracotomy and use of morphine administered intramuscularly or intrapleurally and bupivacaine administered intrapleurally.

Eighteen dogs undergoing lateral thoracotomy at the left fifth intercostal space were randomly assigned to 1 of 3 postoperative analgesic treatment groups of 6 dogs each as follows: group A, morphine, 1.0 mg/kg of body weight, IM; group B, 0.5% bupivacaine, 1.5 mg/kg given interpleurally; and group C, morphine, 1.0 mg/kg given interpleurally. Heart rate, respiratory rate, arterial blood pressure, arterial blood gas tensions, alveolar-arterial oxygen differences, rectal temperature, pain score, and pulmonary mechanics were recorded hourly for the first 8 hours after surgery, and at postoperative hours 12, 24, and 48. These values were compared with preoperative (control) values for each dog. Serum morphine and cortisol concentrations were measured at 10, 20, and 30 minutes, hours 1 to 8, and 12 hours after treatment administration. All dogs had significant decreases in pHa, PaO2, and oxygen saturation of hemoglobin, and significant increases in PaCO2 and alveolar-arterial oxygen differences in the postoperative period, but these changes were less severe in group-B dogs. Decreases of 50% in lung compliance, and increases of 100 to 200% in work of breathing and of 185 to 383% in pulmonary resistance were observed in all dogs after surgery. Increases in work of breathing were lower, and returned to preoperative values earlier in group-B dogs. The inspiratory time-to-total respiratory time ratio was significantly higher in group-B dogs during postoperative hours 5 to 8, suggesting improved analgesia. Blood pressure was significantly lower in group-A dogs for the postoperative hour. Significant decreases in rectal temperature were observed in all dogs after surgery, and hypothermia was prolonged in dogs of groups A and C. Significant differences in pain score were not observed between treatment groups. Cortisol concentration was high in all dogs after anesthesia and surgery, and was significantly increased in group-B dogs at hours 4 and 8. Significant differences in serum morphine concentration between groups A and C were only observed 10 minutes after treatment administration. In general, significant differences in physiologic variables between groups A and C were not observed. Results of the study indicate that the anesthesia and thoracotomy are associated with significant alterations in pulmonary function and lung mechanics. Interpleurally administered bupivacaine appears to be associated with fewer blood gas alterations and earlier return to normal of certain pulmonary function values. Interpleural administration of morphine does not appear to provide any advantages, in terms of analgesia or pulmonary function, compared with its IM administration.

Analgesia↗
PubMed1993

Ovulation without cervical stimulation in domestic cats.

Progesterone was measured by radioimmunoassay of serum collected at monthly intervals for 9 months (April-December) in 24 adult female American short-hair cats (age 2.5-11 years, mean 7.4 years); 20 cats were intact, and four were ovariohysterectomized controls. One of the 20 intact queens was ovariohysterectomized after 7 months, when pyometra was diagnosed. Cats could see and hear one another, and could see and hear male cats housed individually in the same room. Direct contact with other cats was prevented. Tactile stimulation of the cats' hindquarters and perineal regions by handlers was avoided. Serum progesterone concentration > or = 4.8 nmol l-1 was defined as evidence of ovulation. This concentration was exceeded in seven of 20 intact queens (35%) at one or more occurrences of non-coital ovulation; there were 13 such occurrences in all (1-3 per queen). Serum progesterone concentration ranged from 0.2 to 103.4 (mean 14.09 +/- 2.0) nmol l-1 in these seven cats, and was significantly greater than concentrations in the other intact and neutered cats. In the remaining 13 intact and four ovariohysterectomized cats, serum progesterone concentrations ranged from 0.2 to 3.2 (mean 1.24 +/- 1.46) nmol l-1. These data suggest that, at least as far as cats housed in proximity to one another are concerned, intact female cats do not always require cervical stimulation to induce ovulation.

Animals↗
PubMed1993

Concentrations and pulse analyses of adrenocorticotrophin and luteinizing hormone in plasma from dogs in pro-oestrus, oestrus, dioestrus or anoestrus.

Concentrations of adrenocorticotrophin (ACTH) and luteinizing hormone (LH) were measured in plasma collected every 5 min for 190 min from bitches during the oestrous cycle to determine whether mean concentration of ACTH in plasma changes with oestrous cycle phase, and to determine whether plasma ACTH peaks, if present, are related to LH peaks. Radioimmunoassays (RIA) validated for use with dog plasma were used. Mean concentration of ACTH in plasma from pro-oestrous dogs [12.7 +/- 6.0 (SD) range: 5.7-23.1 pmol l-1] was slightly higher (P = 0.085) than that in dogs in oestrus (7.9 +/- 2.1, range: 5.0-11.9 pmol l-1), dioestrus (7.8 +/- 1.5, range: 6.0-9.8 pmol l-1), or anoestrus (7.5 +/- 1.5, range: 5.2-9.2 pmol l-1). Mean concentration of LH in plasma from pro-oestrous dogs [6.0 +/- 7.6 (SD), range: 1.0-19.1 ng ml-1] was higher (P < 0.05) than that in dogs in oestrus (0.6 +/- 0.8, range: undetectable to 2.2 ng ml-1), dioestrus (1.6 +/- 2.1, range: 0.7-5.9 ng ml-1), or anoestrus (1.4 +/- 1.3, range 0.1-3.4 ng ml-1). Plasma ACTH and LH peaks were detected in some dogs during each phase of the cycle. Mean frequency of ACTH peaks (range 0-3 peaks) was similar in all oestrous cycle phases. When data from all phases were combined, mean (+/- SD) number of ACTH peaks in 190 min, interpeak interval and peak duration were 1.7 +/- 1.1, 50 +/- 21, and 34 +/- 7.7 min, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenocorticotropic Hormone↗
PubMed1993

Effects of sample collection and handling on concentration of osteocalcin in equine serum.

A commercially available radioimmunoassay kit for measurement of human osteocalcin was validated for use in horses. For accurate measurement of equine serum osteocalcin, blood samples may be collected at a temperature between 20 and 25 C, then centrifuged within 90 minutes; serum may be stored at -20 C in plastic tubes for up to 26 weeks. Serum may be thawed and refrozen up to 5 times without significant change in measured equine serum osteocalcin concentration. Assay sensitivity was 0.16 ng/ml. Recovery of bovine osteocalcin standard added to equine serum was linear. Intra-assay coefficient of variation (x 100) for 2 equine serum pools was 6.9 (mean +/- SD, 13.9 +/- 1.0 ng/ml) and 7.5 (10.6 +/- 0.8 ng/ml) %. Interassay coefficient of variation for 3 equine serum pools measured in 12 assays was 12.5 (16.1 +/- 2.0 ng/ml), 12.7 (11.5 +/- 1.5 ng/ml), and 24.6 (3.0 +/- 0.7 ng/ml) %. Dilutional parallelism was documented by assaying pooled equine serum at 4 dilutions and correcting the mean result for dilution. Significant change was not observed in equine serum osteocalcin concentration for various time-of-day blood sample collections in horses housed under continuous lighting.

Animals↗
PubMed1992

Effects of chemotherapy and remission on carbohydrate metabolism in dogs with lymphoma.

After a 12-hour fast, blood samples were obtained from 27 dogs with previously untreated lymphoma before and 5, 15, 30, 45, and 60 minutes after an intravenous (IV) challenge with 500 mg/kg dextrose. This procedure was done for each dog before up to five treatments with the IV doxorubicin (30 mg/m2 every 3 weeks). All dogs achieved a complete remission. Samples were assayed for glucose, lactate, and insulin concentrations, and results were compared statistically with those from 16 normal control dogs of similar weight and age undergoing an identical dextrose challenge before and 3 weeks after receiving one dose of IV doxorubicin (30 mg/m2). Glucose, lactate, and insulin concentrations did not change significantly in response to glucose challenge in control dogs after doxorubicin chemotherapy. Lactate and insulin concentrations in untreated dogs with lymphoma were significantly higher than controls. This hyperlactatemia and hyperinsulinemia did not improve when dogs with lymphoma were put into remission with doxorubicin chemotherapy. The results indicate that carbohydrate metabolism is altered in dogs with lymphoma, and that these abnormalities do not improve when a complete remission is obtained with doxorubicin chemotherapy.

Animals↗
PubMed1992

Plasma concentrations of luteinizing hormone and adrenocorticotropic hormone in blood collected during the luteal and follicular phases of the estrous cycle in cows.

Luteinizing hormone (LH) and ACTH concentrations were measured in plasma from 7 cows to determine whether ACTH secretion changes with the phase of the estrous cycle, and to determine whether any ACTH peaks are associated with LH peaks. Blood was collected every 5 minutes for 190 minutes during the luteal and follicular phases of the estrous cycle. Radioimmunoassays were used to measure ACTH and LH in plasma. Mean concentration of ACTH in all cows did not differ significantly between luteal (35.1 +/- 8.0 pg/ml) and follicular (37.5 +/- 9.4 pg/ml) phases of the estrous cycle. Mean concentration of luteal-phase LH of all cows (2.0 +/- 1.1 ng/ml) was significantly (P less than 0.01) lower than mean concentration of follicular-phase LH (5.4 +/- 1.6 ng/ml). Frequency of peaks in ACTH concentration was low during the sampling period. Mean number of luteal-phase ACTH peaks (0.29 +/- 0.49) was not significantly different from that of follicular-phase samples (0.43 +/- 0.530). Unlike ACTH, mean frequency of LH peaks was significantly (P less than 0.05) higher in plasma from cows in the follicular phase of the estrous cycle (2.9 +/- 0.7), compared with that from cows in the luteal phase (0.29 +/- 0.49).

Adrenocorticotropic Hormone↗
PubMed1991

Elevated 25-hydroxy and normal 1,25-dihydroxy cholecalciferol serum concentrations in a successfully-treated case of vitamin D3 toxicosis in a dog.

A 4-y old, 27 kg spayed female German Shepherd dog was observed to ingest one 1-oz package of a rodenticide containing cholecalciferol. An initial serum calcium concentration of 15.7 mg/dl was successfully reduced to normal during 10 d using calcitonin and prednisolone. During that time, the serum 25-hydroxy and 1,25-dihydroxy cholecalciferol concentrations ranged from 637 to 315 ng/ml (normal 32 +/- 6 ng/ml) and 64 to 29 pg/ml (normal 34 +/- 19 pg/ml), respectively. Serum mid-molecule parathyroid hormone concentrations (76 to 97 pcmol/L) were within the normal range (85-140 pcmol/L). These data indicate that hypercalcemia seen in dogs following field exposures to cholecalciferol-containing rodenticides may be associated with elevated 25-hydroxy rather than 1,25-dihydroxy cholecalciferol. Consequently, serum 25-hydroxy cholecalciferol concentrations may be the most conclusive method for diagnosing hypervitaminosis D3 toxicosis in the live dog.

Animals↗
PubMed1990

Hypercalcemia in two cats with squamous cell carcinomas.

Hypercalcemia was identified in 2 cats with squamous cell carcinomas. One cat was referred because of multiple cutaneous tumors; the second cat had metastatic disease from an oral squamous cell carcinoma. In both cats, serum immunoreactive midmolecule parathyroid hormone concentration was within the range determined for clinically normal cats. The high serum calcium concentration in these cats may have resulted from the neoplastic disease, as evidenced by the reduction in serum calcium concentration after decrease in tumor size in response to treatment, and by failure to identify other known causes of hypercalcemia.

Animals↗
PubMed1990

Effects of sample handling on adrenocorticotropin concentration measured in canine plasma, using a commercially available radioimmunoassay kit.

A commercially available radioimmunoassay (RIA) kit for measurement of human adrenocorticotropin (hACTH) was validated for use in dogs. Assay sensitivity was 3 pg/ml. Intra-assay coefficient of variation (x 100; CV) for 3 canine plasma pools was 3.0 (mean +/- SD, 33 +/- 0.99 pg/ml), 4.2 (71 +/- 2.4 pg/ml) and 3.7 (145 +/- 3.7 pg/ml) %. Interassay CV for 2 plasma pools measured in 6 assays was 9.8 (37 +/- 3.6 pg/ml) and 4.4 (76 +/- 3.4 pg/ml) %, respectively. Dilutional parallelism was documented by assaying 2 pools of canine plasma at 3 dilutions and correcting the measured result for dilution. Corrected mean concentrations for the first pool were 33 (+/- 0.99), 36 (+/- 4.3), and 33 (+/- 6.8) pg/ml; corrected mean concentrations for the second pool were 145 (+/- 5.4), 141 (+/- 10.8) and 125 (+/- 3.4) pg/ml. Recovery of 1-39hACTH added to canine plasma (6.25, 12.5, 25.0, 50.0, and 100.0 pg/ml) was linear and quantitative (slope = 0.890, R2 = 0.961). To test whether anticoagulant or the protease inhibitor, aprotinin, influences ACTH concentration in canine plasma, ACTH was measured in canine blood collected in 4 tubes containing anticoagulant: heparin (H), heparin + 500 kallikrein inhibitor units (KIU) of aprotinin/ml (HA), EDTA (E), and EDTA + aprotinin (EA). Plasma ACTH concentration was the same when samples containing H and HA, or HA and E were compared, and was significantly (P less than 0.01) lower in samples containing EA.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenocorticotropic Hormone↗
PubMed1985

The influence of some sample handling factors on progesterone and testosterone analysis in goats.

This study validated the use of commercially available radioimmunoassay kits for measuring the circulating progesterone and testosterone levels of goats. Progesterone and testosterone levels were then assayed in plasma which was collected from 23 does and 8 bucks. Collections from each animal were divided into three sodium fluoride-potassium oxalate (F/OX), one heparin, and one EDTA tubes and also into a tube without anticoagulant. Plasma from an F/OX tube was separated immediately from the blood cells by centrifugation. Serum or plasma was also separated after storage for 24 hours with F/OX, heparin or EDTA anticoagulant at 22 degrees C or with F/OX at 5 degrees C. A significant decline in assayable progesterone occurred in samples stored at 22 degrees C with each anticoagulant used and in the serum sample. Samples stored at 5 degrees C for 24 hours with F/OX anticoagulant contained concentrations of progesterone which did not differ significantly from those in samples where plasma was removed immediately. Assayable testosterone did not change with the anticoagulant used or vary with the storage temperature when F/OX tubes were stored at 5 degrees C and 22 degrees C for 24 hours. Results indicate that sample storage does influence levels of measured progesterone but not testosterone in goats. Progesterone assay is best done on plasma which is immediately separated from blood cells or on samples which are stored at 5 degrees C.

Journal Article↗
PubMed1985

Cytoplasmic estrogen and progesterone receptors in canine endometrium during the estrous cycle.

Estradiol and progesterone receptors (ER, PR) were characterized and measured in cytosols from canine endometrium, using saturation and sucrose-gradient centrifugation radioassays. Both receptors were demonstrated to be steroid- and tissue-specific saturable proteins, which bound the respective steroids with high affinity (dissociation constant [Kd] approximately 10(-9)M). Serum estradiol, progesterone, and endometrial cytosol receptor concentrations and receptor-binding affinity were measured for 25 bitches from which samples were obtained at 5 stages of the estrous cycle (5 bitches each): anestrus (A), the 3rd day of proestrus (P3), the 3rd day of estrus (E3), the 12th day after onset of estrus (E12), and the 28th day after onset of estrus (E28). Mean (+/- SEM) serum estradiol concentrations were 17.0 +/- 2.2 (A), 55.4 +/- 5.0 (P3), 89.4 +/- 24.9 (E3), 41.0 +/- 5.9 (E12), and 50.6 +/- 3.9 (E28) pg/ml. Mean (+/- SEM) serum progesterone concentrations were 0.4 +/- 0.1 (A), 1.5 +/- 0.2 (P3), 17.3 +/- 7.5 (E3), 41.6 +/- 9.5 (E12), and 25.8 +/- 3.2 (E28) ng/ml. Concentrations of ER increased significantly from 1.06 pmol/g of uterus during stage A to a peak concentration of 6.18 pmol/g of uterus at E12, followed by a gradual decrease to 0.69 pmol/g of uterus by E28. The PR concentrations increased from 3.01 pmol/g of uterus in stage A to 17.32 pmol/g of uterus at P3; PR concentrations, thereafter, decreased gradually to 1.85 pmol/g of uterus by E28. Dissociation constants were significantly higher at E12 for the ER (Kd = 2.6645 X 10(-9)M) and at P3 for the PR (Kd = 5.8282 X 10(-9)M) than at the other stages examined, indicating a decrease in receptor affinity during the periods of high receptor concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1984

Evaluation of a test using saralasin to differentiate primary aldosteronism due to an aldosterone-producing adenoma from idiopathic hyperaldosteronism.

We evaluated a new method utilizing saralasin to differentiate primary aldosteronism due to an aldosterone-producing adenoma from idiopathic hyperaldosteronism. The test is based on the marked difference in sensitivity to angiotensin II of aldosterone-producing adenomas and hyperplastic adrenal glands and the partial angiotensin II agonist property of saralasin in low-renin states. Saralasin was infused into 14 patients with primary aldosteronism and the plasma aldosterone responses determined. Plasma aldosterone concentration increased in all eight patients with idiopathic hyperaldosteronism, whereas there was no increase in plasma aldosterone in six patients who had a solitary adenoma. We concluded that saralasin may be a clinically useful, noninvasive tool to distinguish patients with an aldosterone-producing adenoma from those who have idiopathic hyperaldosteronism.

Adenoma↗
PubMed1982

The effect of metoclopramide and dopamine on plasma aldosterone concentration in normal man and rhesus monkeys (Macaca mulatta): a new model to study dopamine control of aldosterone secretion.

Metoclopramide, a dopamine receptor antagonist, increases plasma aldosterone concentration in man, suggesting that dopamine regulates the secretion of aldosterone. In the current study, we administered metoclopramide to rhesus monkeys and normal subjects and compared the time-course and dose-response characteristics of plasma aldosterone. We also examined the effect of dopamine on the plasma aldosterone response to metoclopramide in both species. Six male rhesus monkeys and several normal subjects (five women and two men) were studied on diets providing an estimated daily sodium intake of 70 mg/kg. In both species the peak increase in plasma aldosterone occurred 15 min after metoclopramide was injected. The peak plasma aldosterone value was 3-fold higher than control values. There were no significant changes in PRA, cortisol or potassium, whereas plasma PRL increased 7-fold in the monkeys and 11-fold in the normal subjects. After 0.04 mg/kg metoclopramide, there was no change in plasma aldosterone concentration in the monkeys, whereas aldosterone increased significantly (delta = 3.7 +/- 0.68 ng/dl) in the human subjects. The half-maximal dose of metoclopramide was also higher in the monkeys than in the normal subjects. A dopamine infusion at 4.0 to 8.0 micrograms/kg . min partially suppressed the plasma aldosterone response to metoclopramide in both the human subjects and the monkeys. This study demonstrates that metoclopramide produces dose-related increases in plasma aldosterone concentration in the nonhuman primate that are similar to those in normal man and that the increases can be inhibited by dopamine. We conclude that aldosterone secretion may be under dopamine control and that the rhesus monkey should be an excellent model in which to study further the regulation of aldosterone by dopamine.

Adult↗
PubMedDate not supplied

Effects of neutering on bodyweight, metabolic rate and glucose tolerance of domestic cats.

Few controlled studies have been made of the possible mechanisms and physiological consequences of weight gain after cats have been neutered. In this study, six male and six female cats were gonadectomised and compared with five entire male and six entire female cats, before they were neutered and one and three months later. The neutered males gained significantly more weight (mean [SEM] per cent) than the entire males (30.2 [5.2] v 11.8 [2.3]) and the entire females gained 40.0 (7.3) v 16.1 (3.3) per cent, (P < 0.05). The castrated males gained more weight as fat than the sexually intact males (22.0 [3.3] v 8.8 [4.5] per cent, P < 0.05). There was a significant increase (P < 0.05) in daily food intake after neutering. Spayed females underwent a significant decrease in fasting metabolic rate (83.7 [5.5] v 67.2 [2.3] kcal/kg bodyweight0.75/day P < 0.05). Gonadectomy had minimal effects on serum thyroid hormone concentrations, the resting or fasting metabolic rates in males, or on indices of glucose tolerance.

Adipose Tissue↗