Photoperiod cues play an important role in the timing of puberty in the female lamb. Removal and replacement of photoperiod cues by denervation of the pineal gland and timed melatonin infusions, respectively, indicate that the pathway for transmission of photoperiod information develops well before puberty. This is reinforced by manipulation of artificial photoperiods during various periods of ...

Leptin is secreted by adipose tissue and plays a pivotal role in regulating both body energy homeostasis and reproductive function in rodents. Among livestock, sheep is a seasonal breeder whose reproductive period is initiated by short daylength. We show that plasma leptin and leptin gene expression in perirenal adipose tissue were decreased when ovariectomized Lacaune ewes were exposed to shor...

Daylength controls flowering in many plant species. Early in the twentieth century, Garner and Allard (1920) first described the phenomenon of plants that flower only when daylength is longer or shorter than a particular threshold, named long-day and shortday plants, respectively. Rice is a shortday plant; flowering (termed “heading” in rice and other cereals) is promoted by short daylength. Ho...

Daylength controls flowering in many plant species. Early in the twentieth century, Garner and Allard (1920) first described the phenomenon of plants that flower only when daylength is longer or shorter than a particular threshold, named long-day and shortday plants, respectively. Rice is a shortday plant; flowering (termed “heading” in rice and other cereals) is promoted by short daylength. Ho...

Growth records of 4,270 weanling rabbits born between March 1985 and December 1989 were studied to evaluate the effects of breed and month of birth on postweaning growth performance of four medium-sized breeds. Californian (CAL), New Zealand White (NZW), Palomino (PAL), and White Satin (WS). Traits examined were 28-d weaning weight (WW), postweaning gain (GAIN), attainment of 1,600-g market wei...

Under field conditions, a vast majority of the behavioural and physiological properties of an organism show rhythmic variation with a daily repetition. Although some of these rhythms may be passive systems, driven by the external environment, an increasing body of evidence indicates that, instead, most of the daily rhythms appear to be endogenous, and are merely synchronized by the environment....

Seasonal control of flowering through responsiveness to daylength shows extreme variation. Different species flower in response to long days or short days (SDs), and this difference evolved several times. The molecular mechanisms conferring these responses have been compared in detail only in Arabidopsis thaliana and rice (Oryza sativa) and suggest that a conserved pathway confers daylength res...

T•E gonadal responses of several species of birds exposed to stimulatory daily photoperiods of constant duration conform in that an initial rectilinear relationship exists between the logarithm of testicular weight and time on long days. They conform further in that the rate of photoinduced testicular growth, as determined from the rectilinear relationship, is a function of daylength. These and...

Onion bulb initiation is photoperiod-dependent. Understanding this crucial for adapting new varieties growth at different latitudes, as well aiding germplasm screening the choice of current varieties. This study aims to gain further understanding molecular mechanisms involved in onion bulbing process based on parallels with well-characterised functional clock genes Arabidopsis flowering pathway...