J. HAMMOND

Institute of Animal Physiology of the Slovak Academy of Sciences

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N Ambache

Medical Research Council

Ewa Radwańska

University of Opole

Peter R. Smith

AgResearch

Lara Stone

Cincinnati Children's Hospital Medical Center

R.A. Lawrie

University of Nottingham

H Smiles

Brina Snyder

Southwestern Medical Center

R. B. Heap

Babraham Institute

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University of Cambridge

Consiglio per la ricerca in agricoltura e l’analisi dell’economia agraria

Medical Research Council

The Honourable Society of Lincoln's Inn

Royal College of Surgeons of England

Middlesex Hospital

Royal College of Surgeons in Ireland

Cambridge University Press

Institute of Ophthalmology

National Institute for Medical Research

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Correlation between preovulatory serum estradiol and midluteal progesterone levels during induction of ovulation with Clomid and HCG.

PubMed (1980)

Ewa Radwańska Peter R. Smith J. HAMMOND

Induced ovulation

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Citations (11)

PLASMA PROGESTERONE LEVELS IN PREGNANT AND PSEUDOPREGNANT FERRETS

Reproduction (1974)

R. B. Heap J. HAMMOND

In the ferret, the life-span and growth of the CL is dependent on pituitary hormones.Hypophysectomy arrests the development of the CL (Hill & Parkes, 1932) and causes regression of well-developed CL in pseudopregnant ferrets.Section of the pituitary stalk, however, does not inhibit the function of the CL during the first half of pseudopregnancy (Donovan, 1963).Since ovari- ectomy results in abortion (McPhail, 1935;Galil, 1965), any placental pro- gesterone secretion is apparently inadequate to sustain the normal pregnant state.There is little evidence that placental or uterine factors influence the life-span of the CL.When the products of conception are removed 22, 27 or 30 days post coitum, the CL are indistinguishable 8 to 15 days later from those of normal gestation and oestrus recurs normally, about 7 days after the expected time of delivery (Deanesly, 1967).Oestrus also recurs at about the normal time after total hysterectomy (Deanesly & Parkes, 1933).Hypophysectomy results in abortion even when the operation is carried out in late gestation.In a few ani- mals, however, young were born at the normal time even though the pituitary had been removed between Days 30 and 35 (McPhail, 1935; Galil, 1965).Pregnancy lasts about 42 days, and the life-span and growth of CL is similar in both pregnant and pseudopregnant ferrets (Hammond & Marshall, 1930; B. T. Donovan & J. Oxbrow, personal communication).The purpose of our study was to determine the plasma progesterone concentration in ferrets in order to examine whether the functional activity of the CL, as well as its life- span and growth, was similar in pregnant and pseudopregnant females.A fur¬ ther aim was to see whether plasma progesterone levels declined 5 to 6 weeks after mating, and whether the plasma oestrogen concentration increased.Blood samples were taken by cardiac puncture from ferrets under ether anaesthesia or from animals restrained manually.Plasma was separated by centrifugation from heparinized blood samples.The plasma progesterone concentration was determined by a fluorescence assay (Heap, 1964) or a competitive protein-binding technique (CPB) (Challis, Heap & Illingworth, 1971) in those samples collected under anaesthesia, and by radioimmuno¬ assay (Method A, Heap, Gwyn, Laing & Walters, 1973) in those samples collected from restrained animals.Corpora lutea were dissected from the ovaries of pregnant and pseudopregnant females, stored in A.R. absolute alcohol at -

10.1530/jrf.0.0390149

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Citations (59)

Activity and drug responses of the sheep uterus in relation to reproductive condition

The Journal of Physiology (1949)

N Ambache J. HAMMOND

10.1113/jphysiol.1949.sp004330

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EFFECTS OF CASTRATION AND OF PROGESTERONE IMPLANTATION ON MUSCLE COMPOSITION IN THE FERRET

Journal of Endocrinology (1967)

J. HAMMOND R.A. Lawrie

SUMMARY Longissimus dorsi muscles from intact and castrated male ferrets were investigated at the time of maximum body weight in winter, and muscles from control and progesterone-treated animals in summer. The animals had free access to food throughout. The seasonal decrease in body weight was accompanied by decreased fat concentration in the muscle and by reduction of the subcutaneous and mesenteric fat depots. Implantation of progesterone pellets increased the body and muscle weights of intact males (but not of castrated animals) and also increased intramuscular fat. It may have reversed the seasonal pattern of changes in that the fat in the muscle became more unsaturated. The water content of the muscle decreased only reciprocally in relation to the increased fat content. Progesterone had no obvious effect on the composition of muscle in castrated ferrets. In summer the castrated animals had more intramuscular fat than the intact males at this time; moreover, despite the higher concentration, its degree of unsaturation was greater.

Intramuscular fat

Intramuscular injection

10.1677/joe.0.0380243

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INDUCED OVULATION AND HEAT IN ANOESTROUS SHEEP

Journal of Endocrinology (1944)

J. HAMMOND

If hormone treatment is to be applied commercially on a large scale to control the breeding season, the products used should be cheap and readily available. At the present time such substances are limited to serum gonadotrophin (pregnant mares' serum), and to stilboestrol and other synthetic oestrogens. The investigation here reported concerns the possibility of obtaining fertility in sheep by a single treatment with serum gonadotrophin and stilboestrol. Hammond, Hammond & Parkes [1942] have reviewed much of the work in this field; it is convenient to summarize this briefly, referring to particular findings in connexion with the results as they are presented. Oestrogens will generally induce heat in anoestrous sheep, and will quite often cause ovulation—presumably by stimulating release of ovulating hormone from the pituitary of the treated animal. Serum gonadotrophin and other follicle-stimulating preparations will consistently bring about ovulation; it seems likely that the animal's pituitary is here also

10.1677/joe.0.0040169

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SEVERE EXERCISE INDUCED GLYCOGEN DEPLETION CHANGES DUAL X-RAY ABSORPTIOMETRY AND BIOELECTRICAL IMPEDANCE ON BODY COMPOSITION

International Journal of Exercise Science: Conference Proceedings (2018)

Lara Stone H Smiles J. HAMMOND Brina Snyder

Bioelectrical Impedance Analysis

Dual-Energy X-ray Absorptiometry

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