scholarly journals On the relation between the anterior pituitary body and the gonads.- Part II. The induction of ovulation in the anæstrous ferret

1930 ◽  
Vol 107 (748) ◽  
pp. 39-49 ◽  
Keyword(s):  
Recent Work ◽  
Breeding Season ◽  
Anterior Pituitary ◽  
Reproductive Activity ◽  
Reproductive Organs ◽  
Oestrous Cycle ◽  
Induction Of Ovulation ◽  
The Common ◽  
Reproductive Processes ◽  
Increased Activity

The factors responsible for the alternation of reproductive activity and anæstrous quiesecence are imperfectly known, but in view of much recent work on the regulation of the ovary (Smith and Engle, 1927, Zondek and aschheim, 1927), it is necessary to suppose that the anterior pituitary body is involved. On such a view anæstrus might be caused by inability of the ovary to respond to stimulation from the hypophysis, but it is more reasonable to suppose that the onset of the breeding season is due to increased activity of the anterior pituiary body, and that anæstrus results from decreased activity. In the circumstances it seemed that results of interest might be obtained by the administration of preparations containing the gonad-stimulating principles of the anterior pituitary body to animals during anæstrus. Most of the common labortory animals have no definite anæstrus, and the choice of an animal for work on anæstrus is almost limited to the ferret ot the dog. Of these, the former is obviously more suitable, especially as a considerable amount id now known about its reproductive processes. The work of Marshall (1904), Robinson (1918) and Marshall and Hammond (1930) has made it possible to make the following statements regarding the œstrous cycle in the ferret:- ( a ) The breeding season in restricted and lasts only from April to August. During the remainder of the are the reproductive organs are in a state of quiescent anæstrus.

scholarly journals Reproduction in the common shrew ( Sorex araneus Linnaeus) I—The oestrous cycle of the female

1935 ◽  
Vol 225 (518) ◽  
pp. 1-49 ◽  
Keyword(s):  
Great Britain ◽  
Common Shrew ◽  
Reproductive Organs ◽  
Sorex Araneus ◽  
Oestrous Cycle ◽  
In The Wild ◽  
The Common ◽  
Common Shrew Sorex Araneus ◽  
Reproductive Processes ◽  
Female Reproductive Organs

This paper describes the reproductive processes of the Common Shrew so far as they can be determined from animals caught in the wild state. No account seems to have been given of the oestrous cycle of this species and existing knowledge regarding its life history and breeding habits is far from adequate. This is remarkable since shrews can be obtained readily in almost any rural district on the mainland of Great Britain. An admirable summary of the earlier work is given by Barrett-Hamilton (1911), and little further information, except that provided by Middleton (1931), has been added. The embryology up to the formation of the geminal layers and the development of the placenta have been described by Hubrecht (1890, 1894). The anatomy of the shrew has been described by Ärnbäck-Christie-Linde (1907), but little attention is paid to the female reproductive organs.

scholarly journals The reproductive processes of certain mammals. III.—The reproductive cycle of the male ferret

1932 ◽  
Vol 110 (767) ◽  
pp. 295-312 ◽  
Keyword(s):  
Breeding Season ◽  
Reproductive Cycle ◽  
Reproductive Tract ◽  
Reproductive Activity ◽  
Reproductive Organs ◽  
Interstitial Tissue ◽  
Quiescent Period ◽  
Cyclic Changes ◽  
Reproductive Processes ◽  
Periodic Changes

Cyclic changes in the reproductive organs of male mammals have been studied in a few forms only, but the information available reveals interesting differences in the duration of reproductive activity, and in the correlation between the various organs. Marshall (1911) has described the reproductive cycle in the male hedgehog. Regaud (1904), Tandler and Grosz (1911) and Lecaillon (1909) have studied the mole, but with conflicting results. Rasmussen (1917 and 1918) gives detailed information of the periodic changes in the interstitial tissue of the testis in the woodchuck, and more recently Courrier (1923) has investigated the reproductive cycle in various bats, in the mole, hedgehog, and marmot. The work of Marshall (1904), Robinson (1918) and Hammond and Marshall (1930) has established that in the female ferret the breeding season is restricted and lasts from April to August ; during the remaining months of the year the reproductive organs are in a state of quiescent anœstrus. The first mating occurs in March or April. The present investigation was undertaken in order to determine the duration of the quiescent period in the male ferret and to compare the changes in the testis tubules with those in the interstitial tissue and accessory organs. The condition of the reproductive tract has accordingly been studied at various times of the year, and an attempt has been made to assess the changes in the organs and in their constituent parts.

scholarly journals Different times to perform timed artificial insemination when using a P4/E2/eCG-based protocol in buffalo

2020 ◽  
Vol 50 (4) ◽  
Author(s):  
Nelcio Antonio Tonizza de Carvalho ◽  
Júlia Gleyci Soares de Carvalho ◽  
José Nélio de Sousa Sales ◽  
Rodrigo Caron Macari ◽  
Pietro Sampaio Baruselli
Keyword(s):  
Statistical Analysis ◽  
Breeding Season ◽  
Artificial Insemination ◽  
Oestrous Cycle ◽  
Dominant Follicle ◽  
Induction Of Ovulation ◽  
Pregnancy Diagnosis ◽  
Timed Artificial Insemination

ABSTRACT: The aim of this study was to evaluate different times for timed artificial insemination (TAI) in buffalo submitted to a P4/E2/eCG-based protocol. In this study, 204 buffaloes were distributed into one of two groups (TAI56, n=103 and TAI64, n=101). At a random stage of the oestrous cycle (Day 0 = D0), in the morning (TAI56, a.m.) or afternoon (TAI64, p.m.), buffaloes received an intravaginal progesterone device (P4; 1.0 g) plus EB (2.0 mg i.m.). On D9 a.m. (TAI56) or p.m. (TAI64), the P4 was removed and buffaloes received PGF2a (0.53 mg i.m. sodium cloprostenol) and eCG (400 IU i.m.). On D10 a.m. (TAI56) or p.m. (TAI64), 24 h after P4 removal, buffaloes were treated with EB (1.0 mg i.m.). Buffaloes from TAI56 and TAI64 were inseminated 56 and 64 h after P4 removal (D11, p.m. and D12, a.m., respectively). Ultrasound examinations were performed on D0 to ascertain ovarian follicular status, at TAI to measure the diameter of the dominant follicle (DF) and D42 for pregnancy diagnosis. The statistical analysis was performed using the GLIMMIX procedure of SAS®. There was no difference between TAI56 and TAI64 for the diameter of the DF at TAI and the pregnancy per TAI. It was concluded that TAI 56 or 64 h after P4 removal did not affect fertility in buffaloes submitted to the induction of ovulation with EB. The present research supports that is possible to perform TAI at any time throughout the day in buffalo synchronized during the non-breeding season.

scholarly journals Studies on the hypophysectomized ferret. IV.—Comparison of the reproductive organs during anœstrus and after hypophysectomy

1933 ◽  
Vol 113 (785) ◽  
pp. 530-536 ◽  
Keyword(s):  
Breeding Season ◽  
Anterior Pituitary ◽  
Normal Animal ◽  
Causative Factor ◽  
Reproductive Organs ◽  
Full Activity

In Part II (Hill and Parkes, 1932, b ) it was shown that hypophysectomy of the male ferret during the breeding season caused the testes to regress to a condition very similar to the found in the normal animal during anœstrus. This result suggested that decreased activity of the anterior pituitary body might be the causative factor in anœstrus. The hypophysectomized ferrets regressed from full activity to the anœstrous condition in about one month, i. e ., much more rapidly than the normal animal regresses at the end of the breeding season. This fact showed that hypophyseal activity diminishes gradually at the end of the breeding season and presumably reaches its lowest level when the testes are most atrophic in November. The next problem was to determine whether or not hypophysectomy during November leads to further regression, i. e ., whether the pituitary body is wholly or only partially inactivated at the extreme of the anœstrous period. We have now investigated this question, and also carried out similar experiments on the female.

INDUCTION OF OVULATION IN SHEEP BY ELECTRICAL STIMULATION OF HYPOTHALAMIC REGIONS

1970 ◽  
Vol 46 (3) ◽  
pp. 305-311 ◽  
Author(s):  
F. PRZEKOP ◽  
E. DOMAŃSKI
Keyword(s):  
Electrical Stimulation ◽  
Breeding Season ◽  
Anterior Hypothalamus ◽  
Oestrous Cycle ◽  
Induction Of Ovulation ◽  
Gonadotrophin Secretion ◽  
Hypothalamic Nuclei ◽  
Medial Hypothalamus ◽  
Stimulation Of

SUMMARY Electrical stimulation of the anterior hypothalamus (regions of the supraoptic and anterior hypothalamic nuclei) or of the ventro-medial hypothalamus (infundibular or ventro-medial nuclei) during the last month of anoestrus in ewes induced ovulation within 72 hr., while similar stimulation of the same centres during the breeding season on the 12th day of the oestrous cycle did not advance ovulation. The role of the hypothalamic centres in the control of gonadotrophin secretion and ovulation is discussed in the light of these results.

Reproduction in Sminthopsis-Macroura (Marsupialia, Dasyuridae) .2. The Male

1990 ◽  
Vol 38 (2) ◽  
pp. 207 ◽  
Author(s):  
PA Woolley
Keyword(s):  
Breeding Season ◽  
Sexual Maturity ◽  
Binding Capacity ◽  
Reproductive Activity ◽  
Reproductive Organs ◽  
Histological Changes ◽  
Accessory Glands ◽  
Sminthopsis Macroura ◽  
Sexually Mature ◽  
Androgen Levels

The breeding season of S. macroura extends from June to February, and individual males (both wild- caught and laboratory-reared) are capable of breeding over extended periods during the breeding season, and for up to three seasons, in the laboratory. Gross and histological changes in the reproductive organs and endocrine changes in relation to reproductive activity have been investigated. Males do not appear to reach sexual maturity until the season following that in which they were born, although spermatorrhoea may commence in the season of birth. Testis and epididymis weight of these males, which commence spermatorrhoea late in the season, approximates that of sexually mature males early in the season but androgen levels and the weight of the accessory glands are low in all males except during the early months of the season. The age at which spermatorrhoea commences ranges from 141 to 350 days. The minimum scrota1 width at which it commences is 7.9 mm and the minimum body weight, 14.0 g. The onset of spermatorrhoea is not a function of age or season and in S. macroura should be used with caution as an indicator of impending sexual maturity. Maximum corticosteroid- binding capacity (MCBC) generally exceeded corticosteroid concentration and no androgen-related fall in MCBC was evident.

scholarly journals VI. The Reproductive processes of certain mammals. Part VI. - The reproductive cycle of the female hedgehog

1934 ◽  
Vol 223 (494-508) ◽  
pp. 239-276 ◽  
Keyword(s):  
Breeding Season ◽  
Reproductive Cycle ◽  
Post Partum ◽  
Late Pregnancy ◽  
Reproductive Organs ◽  
Comparative Physiology ◽  
Ecological Data ◽  
Reproductive Processes ◽  
Period Of Gestation ◽  
Length Of Gestation

The hedgehog ( Erinaceus europceus ) is a common British and North European mammal, but no thorough investigation appears to have been made of the reproductive cycle of the female. The present account is designed to fill this gap and as a contribution to the comparative physiology of reproduction. Ecological data are not included. Hubrecht (1889), working at Utrecht on the embryology of the hedgehog, gives the breeding season as June to August and the number of foetuses as 4-8. He regards the hedgehog as a primitive type. Millais (1904) states that the hedgehog breeds twice a year in Great Britain, having its first litter in May or June and its second in August or September, the period of gestation being not more than one month. Five to seven young are born, which are blind at birth ; after about three weeks their spines harden and they assume adult coloration. The young are three-quarters grown by the time winter sets in. Barrett-Hamilton (1911) states that the earliest hedgehog pregnancies occur in April, but he does not include any records. Second litters are found between the middle of August and the end of September ; a late pregnancy is recorded on September 23 in Ireland and an early post-partum animal on September 28 in Scotland. There are generally four or five young, though they may vary in number from 2-9. The length of gestation is given as 4-7 weeks, but as most probably seven weeks on the authority of Lilljeborg (1874). Like Millais, Barrett-Hamilton states that the young are well grown in the same season. Both these writers describe the hedgehog as hibernating from late in November onwards ; the length and extent of hibernation are very variable, however, and the animal is not infrequently found walking about in the winter. In view of the restricted breeding season it seemed likely that the reproductive organs of the female, no less than of the male hedgehog (Marshall, 1911), would show marked changes between the anoestrous and breeding season conditions.

scholarly journals Reproduction in the common shrew ( Sorex araneus Linnæus ). II—Seasonal changes in the reproductive organs of the male

1935 ◽  
Vol 225 (518) ◽  
pp. 51-62 ◽  
Keyword(s):  
Breeding Season ◽  
Seasonal Changes ◽  
Common Shrew ◽  
Reproductive Organs ◽  
Sorex Araneus ◽  
The Body ◽  
Body Weights ◽  
The Common ◽  
Common Shrew Sorex Araneus ◽  
Male Reproductive Organs

The male Common Shrews obtained at the same time and in the same way as the females provide material which throws further light on the duration of life and of the breeding season in this species. This paper deals with the body-weights, weights of the reproductive organs and the occurrence of spermatozoa in the testes. The duration of fertility in the male and in the female are compared. The anatomy of the male reproductive organs is described by Ärnbäck-Christie-Linde (1907) and requires only brief consideration here.

The Semantics of Evidentials

2017 ◽  
Author(s):  
Sarah E. Murray
Keyword(s):  
Recent Work ◽  
Common Ground ◽  
Formal Semantics ◽  
Empirical Support ◽  
Propositional Content ◽  
Primary Data ◽  
Truth Conditional ◽  
The Common ◽  
Issue Content

This book gives a compositional, truth‐conditional, crosslinguistic semantics for evidentials set in a theory of the semantics for sentential mood. Central to this semantics is a proposal about a distinction between what propositional content is at‐issue, roughly primary or proffered, and what content is not‐at‐issue. Evidentials contribute not‐at‐issue content, more specifically what I will call a not‐at‐issue restriction. In addition, evidentials can affect the level of commitment a sentence makes to the main proposition, contributed by sentential mood. Building on recent work in the formal semantics of evidentials and related phenomena, the proposed semantics does not appeal to separate dimensions of illocutionary meaning. Instead, I argue that all sentences make three contributions: at‐issue content, not‐at‐issue content, and an illocutionary relation. At‐issue content is presented, made available for subsequent anaphora, but is not directly added to the common ground. Not‐at‐issue content directly updates the common ground. The illocutionary relation uses the at‐issue content to impose structure on the common ground, which, depending on the clause type (e.g., declarative, interrogative), can trigger further updates. Empirical support for this proposal comes from Cheyenne (Algonquian, primary data from the author’s fieldwork), English, and a wide variety of languages that have been discussed in the literature on evidentials.

Changes in the Male Reproductive Organs of the Dugong, Dugong dugon (Sirenia: Dugondidae) with Age and Reproductive Activity

1984 ◽  
Vol 32 (6) ◽  
pp. 721 ◽  
Author(s):  
H Marsh ◽  
GE Heinsohn ◽  
TD Glover
Keyword(s):  
Reproductive Tract ◽  
Prostate Gland ◽  
Reproductive Activity ◽  
Reproductive Organs ◽  
Seminal Vesicles ◽  
Growth Layer ◽  
Male Reproductive Tract ◽  
Qualitative And Quantitative ◽  
Quantitative Examination ◽  
Testicular Histology

The anatomy and histology of the male reproductive tract of the dugong (Dugong dugon) is described. Each testis and its adjacent epididymis lie immediately caudal to the corresponding kidney. The seminal vesicles are large but there is no discrete prostate gland and the bulbo-urethral glands are also diffuse. Both qualitative and quantitative examination of the testes and epididymides of 59 males whose ages have been estimated from tusk dentinal growth layer counts indicate that the male dugong does not produce spermatozoa continuously, despite the absence of a distinct breeding season. Individual dugongs were observed with testes at all stages between complete quiescence and full spermatogenesis, and only 10 of the 40 mature males had fully spermatogenic testes and epididymides packed with spermatozoa. Androgenic and spermatogenic activity of the testes appeared to be in phase, but the testicular histology of some old males suggested that they may have been sterile for long periods.

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