Categories
Horses

Treatment of Cutaneous Lymphosarcoma

Glucocorticoids remain the mainstay of treatment of cutaneous T cell-rich, B cell lymphoma. Tumor regression is typically noted following the systemic administration of dexamethasone (0.02-0.2 mg/kg IV, IM or PO q24h) or prednisolone (1-2 mg/kg PO q24h). In these authors’ experience, dexamethasone proves more effective than prednisolone in treating lymphosarcoma. Once cutaneous lesions have regressed in size and number, the glucocorticosteroid dose can be gradually tapered. However, a rapid decrease or discontinuation of glucocorticosteroid administration may result in recurrence of cutaneous lesions. Relapses are anecdotally reported to be sometimes more refractory to treatment. Long-term maintenance therapy may be required in these cases. These authors prefer to use a dose of 0.04 mg/kg of dexamethasone (approximately 20 mg for an average-size horse) once daily until significant regression of tumors has occurred; the dose then is reduced to 0.02 mg/kg daily and then to every 48 hours. Intralesional injections of betamethasone or triamcinolone can also be performed with success; this may be impractical when presented with a large number of cutaneous lesions. Topical application of corticosteroid preparations may result in clinical improvement in cases with ulceration; however, results of its use have not been reported. In addition to im-munosuppression, laminitis is a potential side effect of corticosteroid administration.

Exogenous progestins may demonstrate an antiproliferative effect on lymphosarcoma tumors. The exact mechanism of action has not been determined; however, it is believed to be due to the presence of progesterone receptors, which have been demonstrated on both neoplastic and normal equine lymphoid tissues. Progestogens also have glucocorticoid-like activity, which may also account for the response observed in some cases of lymphosarcoma. In one study, progesterone receptors were identified on 67% of the subcutaneous lymphosarcoma tumors that were evaluated (primarily representing T cell-rich, B cell tumors). In the mare diagnosed with simultaneous cutaneous histiolymphocytic lymphosarcoma and a granulosatheca cell ovarian tumor, partial regression of the skin lesions occurred following a ten-day course of the synthetic progestin, altrenogest (0.044 mg/kg q24h PO). A temporary response was also observed after unilateral ovariectomy. The ovarian tumor stained positive for estradiol and led the authors to believe it was estrogen-secreting. The authors speculated that the steroid hormones secreted by the ovarian tumor may have influenced growth of the T cell-rich, B cell tumors by leading to low progesterone concentrations. Anecdotal reports of tumor regression during pregnancy also exist. In one mare with cutaneous T cell lymphosarcoma, regression of nodules was noted after surgical excision, a single intralesional injection of betamethasone (0.04 mg/kg), and an 8-day course of the oral progestogen, megestrol acetate (0.2 mg/kg q24h). Surgical excision may be efficacious in cases in which a single or a small number of cutaneous nodules exists.

The administration of autologous tumor cell vaccines may benefit horses with cutaneous lymphosarcoma. In one report, tumor regression was achieved by using a combination of low-dose cyclophosphamide and autologous tumor cells infected with vaccinia virus. Cyclophosphamide is thought to potentiate the immune response by decreasing suppressor T cell activity. Infection of tumor cells with the vaccinia virus was performed to augment the host antitumor immune response. The treatment protocol included intravenous administration of cyclophosphamide (300 mg/m2) via a jugular catheter over a period of 2 to 3 minutes on days 1 and 36. Immunization with tumor-cell vaccine was performed on days 4 and 21. Response to immunostimulation was confirmed by development of a delayed-type hypersensitivity response to autologous tumor cells injected intradermally in the horse. Potential side effects of cyclophosphamide administration in other species include immunosuppression, enterocolitis, myelosuppression, and hemorrhagic cystitis. No side effects were noted in the horse in this report.

Treatment of epitheliotropic (cutaneous T cell lymphosarcoma) in horses remains speculative because of a paucity of reported cases. Surgical excision of small lesions may be curative. Retinoids and vitamin A analogs inhibit malignant lymphocyte proliferation in human and canine patients with epitheliotropic lymphosarcoma. No reports of the use of retinoids in horses have been published. However, these authors noted no gross or histologic improvement in treating one case of equine epitheliotropic lymphosarcoma with retinoid cream. Side effects included local erythema and signs of irritation after repeated applications.

Investigations as to the effectiveness of radiation therapy and systemic chemotherapy in the management of equine cutaneous lymphosarcoma are needed. Local therapy that consists of intralesional injection of cutaneous nodules with cisplatin has been used successfully in horses with a small number of lesions. Combination chemotherapy that consists of cytosine arabinoside, chlorambucil or cyclophosphamide, prednisone, and vincristine has been reported for use in horses with multicentric lymphosarcoma, as has L-asparaginase.

Categories
Veterinary Drugs

Drugs Acting On The Reproductive System

  • Drugs used to promote gonadal function
  • Sex hormones
  • Prostaglandins
  • Myometrial stimulants
  • Myometrial relaxants
  • Prolactin antagonists
  • Non-hormonal abortificants
  • Drugs for uterine infections

Many drugs are used at different stages of the oestrous cycle to manage the response of the reproductive system; these are summarised in Table Drags affecting the reproductive system.

Table Drags affecting the reproductive system

Indications Species Drug
Synchronisation and regulation of the oestrous cycle and ovulation Horses Altrenogest, Buserelin, Cloprostenol, Dinoprost, Luprostiol
Cattle Buserelin, Cloprostenol, Dinoprost, Etiproston, Gonadorelin, Luprostiol, Progesterone (Eazi-Breed CIDR), Progesterone + estradiol benzoate (Prid)
Sheep, Goats Flugestone acetate, Medroxyprogesterone acetate
Pigs Altrenogest
Stimulation of the onset of cyclical ovarian activity Horses Altrenogest, Buserelin, Chorionic gonadotrophin, Cloprostenol, Deslorelin, Dinoprost, Luprostiol, Serum gonadotrophin
Cattle Buserelin, Chorionic gonadotrophin, Cloprostenol, Dinoprost, Etiproston, Gonadorelin, Luprostiol, Progesterone, Progesterone + estradiol benzoate (Prid), Serum gonadotrophin
Sheep, Goats Flugestone acetate, Medroxyprogesterone acetate, Melatonin, Serum gonadotrophin
Pigs Altrenogest, Chorionic gonadotrophin + serum gonadotrophin (PG600)
Dogs Chorionic gonadotrophin, Serum gonadotrophin
Rabbits Buserelin
Superovulation Cattle Chorionic gonadotrophin, Menotrophin, Serum gonadotrophin, Follicle stimulating hormone (porcine, ovine, recombinant)
Misalliance and pregnancy termination Horses Cloprostenol, Dinoprost, Luprostiol
Cattle Cloprostenol, Dinoprost, Etiproston, Luprostiol
Dogs Aglepristone, Cabergoline, Estradiol benzoate
Induction of parturition Horses Cloprostenol, Dinoprost, Luprostiol
Cattle Cloprostenol, Dexamethasone, Dinoprost, Etiproston, Luprostiol
Sheep Dexamethasone
Pigs Cloprostenol, Dinoprost, Luprostiol
Overt pseudopregnancy Horses (type 1 only) Cloprostenol, Dinoprost
Goats Cloprostenol, Dinoprost
Dogs Cabergoline, Methyltestosterone, Proligestone, Testosterone esters (Durateston)
Suppression of ovarian activity Dogs Medroxyprogesterone acetate, Megestrol acetate, Methyltestosterone, Proligesterone, Testosterone esters (Durateston)
Cats Megestrol acetate, Proligesterone

 

Drugs used to promote gonadal function

Gonadotrophins

Gonadotrophin-releasing hormones

Melatonin

Melatonin advances the time of onset of cyclical ovarian activity in the ewe and doe goat by mimicking the natural production of melatonin by the pineal gland. This gives improved reproductive performance in sheep flocks mated early in the season. A single dose of 18 mg, in a modified-release formulation, is implanted behind the ear. This is carried out 30 to 40 days before the introduction of the ram. It is important that ewes are kept completely separate from rams and also male goats for no less than 30 days after implantation.

In the UK, for Suffolk and Suffolk cross-breeds, the drug should be administered from mid-May to late June, for ram introduction in late June and July. For Mule and Half-bred flocks, melatonin should be administered from early June to late July, for ram introduction from mid-July to late August.

MELATONIN

Indications. Induction of ovulation

Contra-indications. Sexually immature animals

Warnings. Use of drug in ewes suckling lambs at foot may not give optimum results. The drug should not be used at times other than recommended, see notes above

Dose:

Sheep: by subcutaneous administration, 1 implant

PML Regulin (Ceva) UK Implant, m/r, melatonin 18 mg, for sheep

Withdrawal Periods.

Sheep: slaughter withdrawal period nil, milk withdrawal period nil

Sex hormones

Prostaglandins

Myometrial stimulants

Myometrial relaxants

Prolactin antagonists

Pregnancy in bitches is maintained by the presence of corpora lutea; if they regress, pregnancy will be terminated. The presence of corpora lutea is probably dependent upon the luteotrophic support of pituitary-derived prolactin during the second half of the luteal phase of metoestrus and pregnancy.

The prolactin inhibitor cabergoline exerts its effect by inhibiting prolactin release by direct stimulation of dopamine receptors in prolactin-releasing cells in the anterior pituitary. As a consequence, the corpora lutea regress. Towards the end of metoestrus, as the corpora lutea start to regress, there is a concomitant rise in prolactin which is responsible for the overt signs of pseudopregnancy such as behavioural signs and mammary development and lactation. Cabergoline reduces prolactin release and is used for the treatment of overt pseudopregnancy in the bitch. Bromocriptine is a potent dopamine receptor agonist (dopamine receptor stimulant), which inhibits prolactin release from the anterior pituitary gland. Bromocriptine commonly causes side-effects such as vomiting, anorexia, and behavioural changes, which may be severe. Metergoline is a serotonin agonist with actions similar to bromocriptine; it is used to suppress lactation.

CABERGOLINE

Indications. Pseudopregnancy; suppression of lactation; termination of pregnancy ; behavioural modification

Contra-indications. Pregnant animals unless pregnancy termination required; lactating animals unless suppression of lactation required; use directly after surgery while animal still recovering from anesthesia

Side-effects. Transient hypotension, occasionally vomiting or anorexia, transient drowsiness

Warnings. Drug Interactions.

Dose: Doe goats, to suppress lactation, by mouth, 5 micrograms/kg

Dogs: by mouth, 5 micrograms/kg once daily for 4-6 days.

May be mixed with food

Prescription-only medicine: Galastop (Ceva) UK

Oral solution, cabergoline 50 micrograms/mL, for dogs (3 drops = cabergoline 5 micrograms)

Non-hormonal abortificants

Lotrifen is a phenyltriazole isoquinoline which causes embryopathy and abortion in many species such as rats, hamsters, guinea pigs, and dogs. It is most effective in dogs when administered around 20 days of gestation and it is used in dogs for pregnancy termination. The mode of action is unclear: the drug may be embryotoxic, it may reduce blood supply to the gravid uterus, or modify the animal’s immune response.

Drugs for uterine infections

Bacteria will contaminate the uterus of most individuals after normal parturition. However these micro-organisms will soon be eliminated by natural defence mechanisms. The bacteria may originate from the environment and are opportunist pathogens or may be specific venereal pathogens; failure to eliminate them due to impaired defence mechanisms will result in infection. In addition, trauma associated with dystocia and heavy bacterial contamination are also likely to predispose to infection. Uterine infection may be acute, frequently involving all layers of the uterine wall (metritis) or chronic, usually involving the endometrium (endometritis). The former may be fatal. Treatment of metritis includes the use of systemic antimicrobials such as potentiated sulphonamides, oxytetracycline, or semisynthetic penicillins, NSAIDs, and supportive therapy. Chronic infection involving the endometrium can be treated by the intra-uterine infusion of broad-spectrum antimicrobials, administered at the usual therapeutic dosage. In the cow, if a corpus luteum is present, endometritis is best treated by administration of prostaglandin F2alpha or an analogue. In bitches, cystic endometrial hyperplasia and pyometra most commonly occur in the luteal phase of the oestrous cycle (metoestrus). In animals with ‘open’ pyometra with dilated cervix and vaginal discharge, dinoprost is administered at a dose of 250 micrograms/kg for at least 5 days. It is contra-indicated in bitches with very enlarged uteri, animals with heart conditions, and patients with ‘closed’ pyometra. Side-effects occur within 15 minutes of administration and include panting, salivation, vomiting, and whimpering. These symptoms are transient and cease within one hour.

In the UK, the Horserace Betting Levy Board publishes Codes of Practice on contagious equine metritis (CEM) Klebsiella pneumoniae, Pseudomonas aeruginosa; equine viral arteritis (EVA); and equid herpesvirus-1 (EHV-1), which include recommendations for disease prevention and control in breeding horses.

Prescription-only medicine: Metricure (Intervet) UK

Intra-uterine suspension, cephapirin (as cephapirin benzathine) 500 mg, for cattle; dose applicator

Withdrawal Periods.

Cattle: slaughter 2 days, milk withdrawal period nil

Dose:

Cattle: by intra-uterine administration, contents of one applicator. May be repeated after 7-14 days

Prescription-only medicine: Utocyl (Novartis) UK

Pessaries, benzylpenicillin 62.7 mg, formosulphathiazole 1.75 g, streptomycin (as sulfate) 50 mg, for cattle

Withdrawal Periods.

Cattle: slaughter 2 days, milk withdrawal period nil

Dose:

Cattle: by intra-uterine administration, 6 pessaries for prophylaxis only

Categories
Veterinary Drugs

Progestogens

Progestogens are steroids that mimic the effects of progesterone and thus prepare and maintain the female reproductive tract for implantation and pregnancy. They cause development of the mammary glands to the point of lactation. Progestogens exert a negative feedback on the hypothalmic-pituitary axis suppressing the secretion of gonadotrophins, and thereby cyclical ovarian activity, which normally results in oestrus and ovulation. In male animals, progestogens reduce testosterone production by the same action.

In mares, cows, ewes, does, and sows, progestogens are used to synchronise oestrus in groups of animals or enable the occurrence of oestrus to be predicted. Administration of a progestogen for 10 to 14 days will suppress cyclical ovarian activity and oestrus. Longer periods of administration may cause decreased fertility. On removal of the progestogen source, the negative feedback on the pituitary and the hypothalamus is removed and oestrus with subsequent ovulation occurs. This facilitates the use of artificial insemination and stud males. This treatment may also be used in individual animals.

Altrenogest is administered in the feed to mares, gilts, and sows. In sows and gilts, oestrus occurs 5 to 7 days after the last day of treatment. Flugestone and medroxyprogester-one are administered as intravaginal sponges in ewes and does . On withdrawal of the sponge, serum gonadotrophin may be administered as a single dose, the dose varying according to breed and times of administration. This method is used to advance the time of onset of cyclical ovarian activity. Rams are introduced into the flock 48 hours after removal of sponges.

Progesterone is administered to cattle by using a progesterone-releasing intravaginal device (Eazi-Breed CIDR, see also Prid). Prostaglandin F2alpha or an analogue may be administered before removal of the progesterone device to improve the accuracy of synchronisation. Progestogens may be used to stimulate the onset of cyclical ovarian activity in anoestrus mares, cows, ewes, does, and sows. Their effect is evident following withdrawal. Animals are usually mated at the synchronised oestrus, although ewes may be mated at the second oestrus after removal of a progestogen-impregnated sponge. In dogs and cats, medroxyprogesterone, megestrol, and proligestone are used to postpone or suppress oestrus. For guidance, medical treatment (rather than surgical intervention) may be used for prevention of oestrus in animals that are poor surgical risks for ovariohysterectomy and animals from which litters are temporarily not desired. In cats, eosinophilic granuloma and ‘miliary dermatitis’ (crusting dermatosis) are responsive to progestogens because they have a glucocorticoid-like anti-inflammatory effect, although their use for dermatitis is contra-indicated. Prolonged administration of megestrol acetate may lead to side-effects (see below), and oral corti-costeroids or preferably elimination of the causative agent are recommended for the treatment of ‘miliary dermatitis’. Megestrol and medroxyprogesterone may be given for behavioural problems in dogs. Delmadinone is used in the treatment of prostatic hypertrophy, prostatic carcinoma, and perianal tumours. It improves behaviour in some forms of aggression, nervousness, and hypersexuality.

Hydroxyprogesterone has actions similar to other progestogens and has been used to prevent recurrent abortion. Progestogens should be used with caution. All synthetic progestogens differ in their pharmacological profiles and their capacities to produce side-effects in different animal species. For example, although some progestogens may be used to inhibit or retard the growth of certain oestrogen-dependent mammary tumours and treat pseudopregnancy in bitches, it is known that other progestogens can cause or aggravate these conditions.

Progestogens stimulate the proliferative and secretory activity of the uterine endometrium leading to cystic endometrial hyperplasia, mucometra, or pyometra. Therefore, progestogens should not be administered to animals with a history of vaginal discharge or reproductive abnormalities, sexually immature animals, or dogs and cats intended for breeding. When used for suppression of oestrus in dogs and cats, animals should be allowed to have a normal cycle every 18 to 24 months.

Progestogens antagonise the hypoglycaemic effects of insulin and therefore should not be given to diabetic animals. The possibility of pre-existing disease should be considered when treating patients requiring long-term progestogen therapy. Some progestogens, such as megestrol acetate, may induce profound adrenal cortical suppression and possibly hypoadrenacortical syndrome on rapid withdrawal. Progestogens may induce acromegaly in entire bitches. Subcutaneous injection of progestogens may cause hair discoloration and localised alopecia and thinning of the skin. Injection should be given in an inconspicuous area, such as the inner fold of the flank or medial aspect of the thigh. Some patients given progestogens may develop a tendency for obesity or a change in temperament.

Preparations containing progestogens should be handled with care, particularly by women of child-bearing age. Impervious gloves and suitable protective overalls should be worn when in contact with such preparations.

ALTRENOGEST

Indications. See under Dose

Contra-indications. Male animals, immature animals, animals with uterine infection

Warnings. Partly consumed medicated feed should be safely destroyed and not given to any other animal; correct dose must be given because underdosing may lead to formation of cystic ovaries. Care must be taken to avoid any contact between preparations of the drug and women of child-bearing age; the manufacturer recommends that women of child-bearing age should not be associated with the use of these preparations; women with irregular menstrual periods after exposure to these preparations should consult their doctor; operators should wear protective clothing when handling the product

Dose: By addition to feed.

Horses: anoestrus (not deep anoestrus), suppression of prolonged oestrus during the transitional phase before the resumption of normal cyclical ovarian activity, 44 micrograms/kg daily for 10 days

Suppression and control of oestrus in cycling mares, 44 micrograms/kg daily for 15 days

Pigs: (gilts) synchronisation of oestrus, 20 mg daily for 18 days; (sows) synchronisation of oestrus, 20 mg daily for 3 days, starting on day of weaning

Prescription-only medicine: Regumate Equine (Intervet) UK

Oral solution, for addition to feed, altrenogest 2.2 mg/mL, for horses

Withdrawal Periods. Should not be used in horses intended for human consumption

Prescription-only medicine: Regumate Porcine (Janssen) UK

Oral suspension, for addition to feed, altrenogest 20 mg/unit dose, for pigs; metered-dose applicator (1 unit dose = 5 mL)

Withdrawal Periods.

Pigs: slaughter 15 days

DELMADINONE ACETATE

Indications. Treatment of hypersexuality, relief of prostatic hypertrophy, perianal (circumanal, hepatoid) gland tumours; certain behavioural problems

Contra-indications. Concurrent administration of other progestogens

Side-effects. Transient reduction in fertility and libido; transient increased appetite, polydipsia and polyuria; discoloration of hair at injection site

Warnings. Clinical response to treatment is 2-4 days

Dose:

Dogs, cats: by subcutaneous or intramuscular injection, 1-2 mg/kg depending on the weight of the animal and severity of the condition, repeat dose after 8 days if no improvement. Repeat dose every 3-4 weeks in animals showing improvement

Prescription-only medicine: Tardak (Pfizer) UK

Injection, delmadinone acetate 10 mg/mL, for dogs, cats

FLUGESTONE ACETATE

(Flurogestone acetate)

Indications. See under Dose

Contra-indications. Ewe lambs, ewes not previously bred

Warnings. Operators should wear protective gloves when handling sponges; the physical and nutritional state of the flock must be good for use in non-breeding season

Dose: Sheep, goats: synchronisation of oestrus during the breeding season, by intravaginal administration, one 30-mg sponge. Remove after 14 days Induction of oestrus and ovulation during non-breeding season, advancement of breeding season, by intravaginal administration, one 30-mg sponge. Remove after 12 days, followed within 6 hours by serum gonadotrophin, by subcutaneous or intramuscular injection, 500 units

Prescription-only medicine: Chronogest (Intervet) UK

Vaginal sponge, flugestone acetate 30 mg, for sheep

Disinfectant

Liquid concentrate, benzalkonium bromide 5%. To be diluted before use

Dilute 1 volume in 90 volumes water

Withdrawal Periods.

Sheep: slaughter 14 days after removal of sponge, should not be used in sheep producing milk for human consumption

Note. After each application, the sponge applicator should be wiped clean and placed in the supplied disinfectant. Do not use alcohols, cresols, phenols, sheep dip or other disinfectants

MEDROXYPROGESTERONE ACETATE

Indications. See under Dose; behaviour modification

Contra-indications. Use in bitches primarily intended for breeding purposes, use before first oestrus, pregnant animals, previous history of genito-urinary disease, persistant or abnormal vaginal discharge, irregular oestrus or nymphomania, pseudopregnancy, mammary tumours, pro-oestrus, oestrus, or metoestrous stage of oestrous cycle; diabetes mellitus; use in maiden ewes, ewes with vaginal discharge or just after abortion

Side-effects. Thinning of skin, thinning and discoloration of hair at injection site; mammary hyperplasia or nodules; weight gain; cystic endometrial hyperplasia

Warnings. Injection should be given in inconspicuous site; owners should be warned that return to oestrual cycling is variable after long-term treatment; operators should wear protective gloves when handling sponges and take care to avoid damaging the vagina; the sponge should be removed and ewes examined if there is excessive straining after insertion or blood on the applicator; all sponges should be removed after 17 days

Dose:

Sheep, goats : synchronisation of oestrus, by intravaginal administration, one 60-mg sponge. Remove after 13-17 days

Induction of oestrus and ovulation during non-breeding season, advancement of breeding season, by intravaginal administration, one 60-mg sponge. Remove after 13-17 days and by subcutaneous or intramuscular injection, serum gonadotrophin, 300-750 units, given at time of sponge removal (dose dependent on breed and time interval to normal breeding)

Dogs: prevention of oestrus, by subcutaneous injection, 50 mg given in anoestrus. Repeat after 6 months

Prescription-only medicine: Promone-E (Pfizer) UK

Injection, medroxyprogesterone acetate 50 mg/mL, for dogs

Prescription-only medicine: Veramix Sheep Sponge (Pfizer) UK

Vaginal sponge, medroxyprogesterone acetate 60 mg, for sheep

Withdrawal Periods.

Sheep: slaughter 14 days after removal of sponge, should not be used in sheep producing milk for human consumption

Note. After each application, the sponge applicator should be wiped clean and washed in water containing a suitable disinfectant such as cetrimide 0.5-1.0%. Do not use alcohols, cresols, phenols, or similar disinfectants

MEGESTROL ACETATE

Indications. See notes above and under Dose; behaviour modification

Contra-indications. Diabetes mellitus; male dogs intended for breeding

Side-effects. Rarely excess libido; occasionally lethargy, weight gain; mammary hypertrophy

Warnings. Not more than 2 courses of treatment for postponement of oestrus should be given per 12-month period in bitches; owners should be warned that the time interval to the subsequent oestrus is variable

Dose: By mouth.

Dogs. Females: prevention of oestrus, 2 mg/kg daily for 8 days or 2 mg/kg daily for 4 days then 500 micrograms/kg daily for 16 days, given at pro-oestrus Postponement of oestrus, 500 micrograms/kg daily for up to 40 days given in anoestrus and 7-14 days before postponement is required

Males: behavioural problems, see section 6.11.11

Cats: miliary dermatitis, eosinophilic granuloma, 2.5-5.0 mg every 2-3 days until lesions regress then once weekly until satisfactory response. Then maintenance dose of 2.5 mg every 7-14 days if required

Females: prevention of oestrus, 5 mg daily for 3 days given in pro-oestrus

Postponement of oestrus, 2.5 mg once weekly for up to 30 weeks and given in anoestrus

Prescription-only medicine: Ovarid (Schering-Plough) UK

Tablets, scored, megestrol acetate 5 mg, 20 mg, for dogs, cats

PROGESTERONE

Indications. See under Dose

Contra-indications.

Side-effects. See notes above

Dose:

Cattle: induction of oestrus and ovulation in anoestrus, by intravaginal administration, 1 device. Remove after 7-12 days

Synchronisation of oestrus and ovulation, by intravaginal administration, 1 device. Remove after 7-12 days and administration of prostaglandin F2alpha (see site for dosage) at time of removal, or at any time from 6 days after insertion. GnRH (buserelin and gonadorelin, section 8.1.2) may be used in conjunction with intravaginal progesterone to stimulate follicular growth

Prescription-only medicine: Eazi-Breed CIDR (ART) UK

Intravaginal device, progesterone 1.9 g, for cattle

Withdrawal Periods.

Cattle: slaughter 6 hours after removal of device, milk withdrawal period nil

PROLIGESTONE

Indications. See notes above and under Dose

Contra-indications. Use in bitches treated previously with oestrogens or progestagens for pseudopregnancy

Side-effects. Thinning of skin, thinning and discoloration of hair at injection site; mammary hyperplasia; transient weight gain and lethargy; cystic endometrial hyperplasia

Warnings. Injection should be given in inconspicuous site; occasional anaphylactic reaction; use with caution in diabetic animals; for suppression of oestrus bitches, should be in early pro-oestrus when treated; bitches may accept male for a few days after treatment and contact with males should be prevented until signs of oestrus have regressed

Dose: By subcutaneous injection.

Dogs: permanent postponement of oestrus, 10-33 mg/kg (larger animals receive proportionally lower doses), repeat after 3, 4, and 5 months

Temporary postponement of oestrus, suppression of oestrus at onset of pro-oestrus, 10-33 mg/kg as a single dose Pseudopregnancy, 10-33 mg/kg. May repeat after 1 month if required

Cats: postponement and suppression of oestrus, 100 mg Miliary dermatitis, 33-50 mg/kg, repeat every 4 months, or more frequently depending on response

Ferrets: to prevent problems associated with prolonged oestrus, 50 mg/animal

Prescription-only medicine: Delvosteron (Intervet) UK

Injection, proligestone 100 mg/mL, for dogs, cats, ferrets