Differentiating Spayed from Intact Queens

Axnner, E., T. Gustavsson, et al. (2008). "Estradiol measurement after GnRH-stimulation as a method to diagnose the presence of ovaries in the female domestic cat." Theriogenology 70(2): 186-191.

Spaying is routinely recommended for population control in cats, as well as for specific health benefits and to avoid unwanted behaviors. It can be difficult to determine if a queen with an unknown history and no estrous activity is spayed or intact. In addition, one of the most common feline reproductive problems encountered by practicing veterinarians is ovarian remnant syndrome. A test that differentiates intact from spayed queens would be valuable. A commercially available luteinizing hormone assay (Witness LH, Synbiotics) has been marketed for this purpose, but is not available world-wide. GnRH induces release of follicle-stimulating hormone (FSH) and LH from the pituitary gland. FSH stimulates estradiol production by granulosa cells in ovarian follicles. The aim of this study was to evaluate if it is possible to differentiate between spayed and sexually inactive intact queens by measurement of plasma estradiol before and/or after stimulation with a GnRH-analogue, buserelin (Receptal, Intervet). Two groups of female cats (11 spayed, 11 intact) were treated with buserelin after baseline measurement of plasma estradiol and progesterone. A second blood sample was collected two hours later. Median estradiol increased after stimulation with buserelin in intact but not in spayed females. There was no overlap between the two groups of cats. Measurement of plasma estradiol concentration 2 hours after stimulation with a GnRH-analogue seems to be a reliable method to diagnose the presence of ovarian tissue in the female cat.

Axnner, E., T. Gustavsson, et al. (2008). "Estradiol measurement after GnRH-stimulation as a method to diagnose the presence of ovaries in the female domestic cat." Theriogenology 70(2): 186-191.

Spaying is routinely recommended for population control in cats, as well as for specific health benefits and to avoid unwanted behaviors. It can be difficult to determine if a queen with an unknown history and no estrous activity is spayed or intact. In addition, one of the most common feline reproductive problems encountered by practicing veterinarians is ovarian remnant syndrome. A test that differentiates intact from spayed queens would be valuable. A commercially available luteinizing hormone assay (Witness LH, Synbiotics) has been marketed for this purpose, but is not available world-wide. GnRH induces release of follicle-stimulating hormone (FSH) and LH from the pituitary gland. FSH stimulates estradiol production by granulosa cells in ovarian follicles. The aim of this study was to evaluate if it is possible to differentiate between spayed and sexually inactive intact queens by measurement of plasma estradiol before and/or after stimulation with a GnRH-analogue, buserelin (Receptal, Intervet). Two groups of female cats (11 spayed, 11 intact) were treated with buserelin after baseline measurement of plasma estradiol and progesterone. A second blood sample was collected two hours later. Median estradiol increased after stimulation with buserelin in intact but not in spayed females. There was no overlap between the two groups of cats. Measurement of plasma estradiol concentration 2 hours after stimulation with a GnRH-analogue seems to be a reliable method to diagnose the presence of ovarian tissue in the female cat.

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Glucocorticoids and Cats

Lowe, A. D., K. L. Campbell, et al. (2008). "Clinical, clinicopathological and histological changes observed in 14 cats treated with glucocorticoids." Vet Rec 162(24): 777-83.

Glucocorticoids such as prednisone and prednisolone are commonly used to treat a variety of conditions in feline medicine. Adverse effects from this class of drugs in cats are well known, and may be dose-dependent. In this study, 14 cats were given immunosuppressive doses of prednisolone (4.4 mg/kg/day) or dexamethasone (0.55 mg/kg/day) for 8 weeks. Complete blood counts, serum biochemistry profiles and urinalyses were performed on days 0 and 56, and liver biopsies were taken on day 56. Significant increases were noted in mean white blood cell counts, neutrophil counts, and monocyte counts. Significant decreases were noted in mean lymphocyte counts and eosinophil counts. Consistent increases in serum albumin, glucose, triglycerides and cholesterol were observed. A steroid hepatopathy was present in varying degrees in all liver biopsies. One cat developed clinical signs believed to be related to the therapy, such as icterus and curling of the pinnae.
>> PubMed Abstract

Related articles:
Sharkey, L. C., T. Ployngam, et al. (2007). "Effects of a single injection of methylprednisolone acetate on serum biochemical parameters in 11 cats." Vet Clin Pathol 36(2): 184-7.
>> PubMed Abstract

More on cat health: Winn Feline Foundation Library

Lowe, A. D., K. L. Campbell, et al. (2008). "Clinical, clinicopathological and histological changes observed in 14 cats treated with glucocorticoids." Vet Rec 162(24): 777-83.

Glucocorticoids such as prednisone and prednisolone are commonly used to treat a variety of conditions in feline medicine. Adverse effects from this class of drugs in cats are well known, and may be dose-dependent. In this study, 14 cats were given immunosuppressive doses of prednisolone (4.4 mg/kg/day) or dexamethasone (0.55 mg/kg/day) for 8 weeks. Complete blood counts, serum biochemistry profiles and urinalyses were performed on days 0 and 56, and liver biopsies were taken on day 56. Significant increases were noted in mean white blood cell counts, neutrophil counts, and monocyte counts. Significant decreases were noted in mean lymphocyte counts and eosinophil counts. Consistent increases in serum albumin, glucose, triglycerides and cholesterol were observed. A steroid hepatopathy was present in varying degrees in all liver biopsies. One cat developed clinical signs believed to be related to the therapy, such as icterus and curling of the pinnae.
>> PubMed Abstract

Related articles:
Sharkey, L. C., T. Ployngam, et al. (2007). "Effects of a single injection of methylprednisolone acetate on serum biochemical parameters in 11 cats." Vet Clin Pathol 36(2): 184-7.
>> PubMed Abstract

More on cat health: Winn Feline Foundation Library

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Insulins for Cats: Glargine, PZI, Lente

Marshall, R. D., J. S. Rand, et al. (2008). "Glargine and protamine zinc insulin have a longer duration of action and result in lower mean daily glucose concentrations than lente insulin in healthy cats." Journal of Veterinary Pharmacology and Therapeutics 31(3): 205-212.

This 3-way crossover study was designed to evaluate the effects of glargine (Lantus®), protamine zinc (PZI), and lente insulins in 9 healthy cats. Plasma concentrations of insulin and glucose were determined for 24 hours after a single subcutaneous injection of each insulin at 3-day intervals. Time to onset of action did not differ among insulins. The mean time to the glucose nadir was longer for glargine (14 hours), than for PZI (4 hours) or lente (5 hours). PZI was biphasic, with nadirs at 4 and 14 hours. The nadir glucose value did not differ among insulin types. The duration of action was similar for glargine and PZI, and was longer than for lente. A larger study is required to further compare glargine and PZI insulins in cats.
>> PubMed abstract

Related articles:
Weaver, K. E., E. A. Rozanski, et al. (2006). "Use of glargine and lente insulins in cats with diabetes mellitus." J Vet Intern Med 20(2): 234-8.
>> PubMed abstract

Rand, J. (2006). "Editorial: glargine, a new long-acting insulin analog for diabetic cats." J Vet Intern Med 20(2): 219-20.
>> PubMed abstract

More on cat health: Winn Feline Foundation Library

Marshall, R. D., J. S. Rand, et al. (2008). "Glargine and protamine zinc insulin have a longer duration of action and result in lower mean daily glucose concentrations than lente insulin in healthy cats." Journal of Veterinary Pharmacology and Therapeutics 31(3): 205-212.

This 3-way crossover study was designed to evaluate the effects of glargine (Lantus®), protamine zinc (PZI), and lente insulins in 9 healthy cats. Plasma concentrations of insulin and glucose were determined for 24 hours after a single subcutaneous injection of each insulin at 3-day intervals. Time to onset of action did not differ among insulins. The mean time to the glucose nadir was longer for glargine (14 hours), than for PZI (4 hours) or lente (5 hours). PZI was biphasic, with nadirs at 4 and 14 hours. The nadir glucose value did not differ among insulin types. The duration of action was similar for glargine and PZI, and was longer than for lente. A larger study is required to further compare glargine and PZI insulins in cats.
>> PubMed abstract

Related articles:
Weaver, K. E., E. A. Rozanski, et al. (2006). "Use of glargine and lente insulins in cats with diabetes mellitus." J Vet Intern Med 20(2): 234-8.
>> PubMed abstract

Rand, J. (2006). "Editorial: glargine, a new long-acting insulin analog for diabetic cats." J Vet Intern Med 20(2): 219-20.
>> PubMed abstract

More on cat health: Winn Feline Foundation Library

Read More