Wilbor O. Wilson

Cellular changes in the gonads, livers and adrenal glands of Japanese quail as affected by the insecticide Kepone.

Abstract A histological study of normal reproductive organs, livers, and adrenal glands from immature and adult Japanese quail of both sexes and of quail fed 200 ppm of the insecticide Kepone under long and short photoperiods was carried out. Kepone increased cellular proliferation, cytodifferentiation and tubular gland formation in the oviducts of immature quail when kept under 6 hr of light and 18 hr of darkness (6L: 18D) and 16 hr of light and 8 hr of darkness (16L: 8D). No cellular changes were noted in the oviducts from laying quail. Ovarian tissue from Kepone-treated quail contained more primary oocytes and smaller follicles when compared to the control birds. Liver cells from all experimental birds were filled with large, lipidlike inclusions. Hypertrophy of adrenal cortical and medullary cells was noted in all Kepone-treated birds. A detrimental effect of Kepone was recorded in the testes of immature and adult quail under the 16L: 8D light regimen. Highly dilated seminiferous tubules, reduced germinal epithelium and spermatozoa, and abundant intraluminal cellular debris were common. The results indicate that the insecticide Kepone has an estrogenlike effect on the oviducts of immature females and on the testes of both immature and mature males.

Eyes Have a Role in Photoperiodic Control of Sexual Activity of Coturnix

In blinded Japanese quail (Coturnix coturnix japonica) encephalic photoreception of the stimulus from long photoperiods is sufficient to induce and maintain normal gonadal function in females (egg laying) and in males (enlargement of the cloacal gland). However, the termination of sexual activity by short days is dependent on these birds having experienced long days at the time of blinding.

Photoperiods and age as factors modifying the effects of kepone in Japanese quail.

Abstract Immature Japanese quail ( Coturnix coturnix japonica ) of both sexes fed 200 ppm of the insecticide Kepone, when exposed to 16 hr of light per day, had significantly enlarged reproductive organs, livers and adrenal glands. After a reduction in the photoperiod high mortality occurred in only the birds previously fed Kepone. Administration of Kepone to adult females while egg-laying did not affect the weight of reproductive organs or livers. In adult males of the same age testes and livers were greatly enlarged. In both sexes of adult birds, the adrenals were enlarged. Subsequent exposure to reduced photoperiod of the Kepone-fed adult quails of both sexes produced no mortality. In males fed Kepone, testicular regression was recorded much earlier than in controls. Previous ingestion of Kepone affected neither the cessation of egg-laying nor the regression of the ovary. Kepone exerted its effects primarily on the immature quail of both sexes and to a lesser degree on adults. An estrogenic action of Kepone was indicated by increased oviduct weight of young females on a photoperiod of 6 hr light and 18 hr dark per day. In adult males the major estrogenic effect was increased liver weight.

PHOTOCONTROL OF OVIPOSITION IN GALLINACEOUS BIRDS.

Introduction Gallinaceous birds lay eggs in sequences of varying lengths a t more or less regular intervals. The term “sequence,” as used, refers to the total eggs laid on successive days; i t is sometimes called a clutch. The frequency of sequences is designated as rhythm of lay. Successive eggs usually are laid an hour or two later each day. This time interval is known a5 the lag. Ovulation occurs the day before oviposition, and usually quite early in the day. Approximately 24 to 26 hours elapse from the time the ovum is released until i t is oviposited. Time of ovulation apparently is not controlled by time of oviposition. Warren and Scott (1935) effected a premature expulsion of the egg from the uterus with no resultant change in time of the next ovulation. However, time of ovulation can influence time of oviposition. When Fraps (1942) induced ovulation three to six hours prematurely, the next egg in the sequence was laid prematurely by the same amount of time. The influence of hormones from exogenous sources on the release of the ovulation-inducing, or luteinizing hormone (LH) by the chicken has been studied by several investigators. Fraps et al. (1942) induced premature ovulation by injection with gonadotropins. The average interval between injection and the resulting ovulation of the follicle was 7.5 hours, with a range of 6.5 to 8.5 hours. Rothchild and Fraps (1949), working with hypophysectomized birds, observed that the interval between release of LH and ovulation was the same for all follicles of a given sequence. They interpreted this to mean that successively later hours at which ovulation occurs within a clutch are due to successively later releases of the ovulating hormones. Hosoda et al. (1956) reported that i t was possible to force ovulation in fasting hens by daily treatment with gonadotropins. After seven to eight days of starvation, during which time White Leghorns were injected daily with 0.1 or 0.5 mg. of LH preparation, ovulation could be induced. The time between injection and ovulation was approximately eight hours. Larger doses did not stimulate ovulation of immature follicles. The time required for progesterone to induce initial follicle ovulation falls within very narrow limits, according to Fraps (1955). He found that

Diurnal variation in gonadotropic potency of the adenohypophysis of Japanese quail (Coturnix coturnix japonica).

Abstract Japanese quail ( Coturnix coturnix japonica ) were raised from hatch under one of the following light regimens: continuous light, repeated cycles of 16 hours light and 8 hours darkness (16L:8D), 14L:10D, 6L:6D, and 8L:16D. The gonadotropic potencies of the acetone-dried adenohypophysis were determined for groups of 4-week-old males killed after exposure to various periods of light and of dark. The potencies were estimated by bioassay in which the weight increase in the testes of 2-week-old male coturnix that were reared under 8L:16D was used. In quail exposed to continuous light, gonadotropic potency of the adenohypophysis did not differ significantly among birds killed at 8-hour intervals. In birds subjected to 16L:8D, 14L:10D or 6L:6D, the potency was higher at the end of the light period than at 3 or 4 hours after beginning of darkness. No significant difference was observed in potencies during darkness. The results indicate that gonadotropin content in the adenohypophyses from immature male coturnix reared under certain light regimens changes with the daily light-dark rhythms.

THE EFFECT AND AFTER-EFFECT OF VARIED EXPOSURE TO LIGHT ON CHICKEN DEVELOPMENT

The present experiments were designed to determine the effects of:a. Total daily amount of lightb. Intensity of lightc. Frequency of light intervalson the growth and development of Leghorn chickens.a. Total daily amount of light exposures: The first test dealt with the effect of supplementing natural light with continuous light. Continuous light improved body weight of all birds and testes size of males at 7 weeks, but impaired feather development. Continuous lighting delayed sexual maturity of pullets, and growth in both sexes was retarded until they reached 20 weeks of age.In the second experiment under suboptimal light intensities, light exposure has no effect on body size after 12 weeks of age. Rate of sexual development was increased by larger daily exposures to light. These effects were more pronounced when treatments were applied to pullets over 90 days old than during earlier stages of development.b. Intensity of light: Three light intensities were applied to growing birds: 0.0-0.4 foot-candles, 0...

Ontogeny of the photosexual response in intact and castrated Coturnix.

Abstract This study examined the posthatch development of the photosexual response in intact and castrated coturnix. Two criteria were used to determine the onset of the effects of light: (1) the ability to distinguish between long and short photoperiods; and (2) the first increase in serum LH concentration. The results indicated that the onset of the photosexual reflex occurred between 3 and 4 weeks of age in females and between 17 and 21 days of age in males. The immature testes was shown to be involved in the developmental process of the photosexual reflex.

Photoperiodism in the common coturnix (Coturnix c. japonica) male

Abstract Testicular growth of young and mature coturnix ( Coturnix c. japonica ) on intermittent light was observed. Five experiments were designed to determine if intermittent symmetrical photoperiods were more effective when they occurred during the photosensitive phase. A brief review of night interruption and resonance experiments with male birds is also given. All birds received a total of 12 hours of light per day. The number of light cycles per 24 hours and hours of light and dark per cycle were as follows: 1(LD12:12), 2(LD6:6), 3(LD4:4) and 4(LD3:3). Testicular growth differed among groups depending on the number of photoperiods received. The most effective light treatment was the 4(LD3:3) and least effective was 1(LD12:12). These results are interpreted on the basis of a circadian rhythm in photosensitivity.

Effect of acute and chronic elevated air temperatures, constant (34°) and cyclic (10–34°), on brain and heart norepinephrine of male Japanese quail

Abstract Endogenous levels and turnover of brain and heart norepinephrine (NE) of male quail ( Coturnix coturnix japonica ) were fluorometrically determined after exposure to either acute (6 hr) and chronic (5 week) 34° or cyclic temperature (10–34°) stress. α-Methyl- p -tyrosine (αMT) was used to induce depletion of endogenous norepinephrine levels by inhibition of tyrosine hydroxylase. The differences between the levels of treated and control birds (22°) were regarded as changes in turnover. High ambient temperature (34°) stress for 6 hr increased brain NE levels, decreased heart NE levels, and increased turnover of brain and heart NE. However, chronic exposure (5 weeks) to 34° and cyclic temperature (10–34°) did not increase turnover of brain NE, though chronic exposure to 34° increased heart NE turnover. The results indicate that there is increased noradrenergic activity during acute thermal exposure, and that after acclimation to thermal stress for 5 weeks, the noradrenergic activity declines in the brain, though it persists in the heart. Chronic exposure to 34° significantly reduced heart, adrenal, and testes weights, but exposure to chronic cyclic temperatures (10–34°) only reduced adrenal weight.

Persistency of egg production of common coturnix is affected by early light regimens

Abstract The quantity and quality of light during the growing period was studied in 3 experiments to determine the effect on subsequent egg production of Coturnix coturnix japonica . Females were individually caged and kept in climatic chambers. Either short days (LD 8:16), or long days (LD 16:8) were given from hatching until 10 weeks of age. Later the birds were exposed to short and long light periods of 6 weeks duration alternately, until 34 or 36 weeks of age. Parameters measured were age at first egg, total egg production, and rate of lay under LD 8:16. Although no treatment resulted in all of the birds of a group being persistent layers, rearing on short-days, blinding and fluorescent light each contributed to persistency in adults. Early light regimens in coturnix are important in establishing persistency of egg production performances as adults.