—We studied the breeding biology of the Panamanian subspecies of the Yellow-crowned Parrot, Amazona ochrocephala panamensis, during 1997–1999 in the province of Chiriquı́, Panama, to provide basic information regarding the breeding behavior and reproductive success of these parrots in their natural habitat. We recorded parrot behaviors throughout the reproductive period, monitored nest success, ...

In Africa, birds inhabiting forested regions are less seasonal in their activities than those from open areas. In order to study annual cycles in forest regions of South western Nigeria, West African Thrushes (Turdus pelios) were mist-netted and banded during the last two weeks of each month. The nest is a cup-shaped structure built out of grasses, herbs, weeds, roots and earth laid out in a cl...

abstract the aim of this study was to evaluate the monthly variations of triiodothyronine (t3), thyroxine (t4), t3 tot4 ratio, thyroid stimulating hormone (tsh), and testosterone in dallagh rams during the breeding and non breeding seasons. four healthy mature rams (3-4 years old) with an average body weight of 45±5 kg were selected and kept in the same conditions. blood samples were collected ...

In many seabird studies, single annual proxies of prey abundance have been used to explain variability in breeding performance, but much more important is probably the timing of prey availability relative to the breeding season when energy demand is at a maximum. Until now, intraseasonal variation in prey availability has been difficult to quantify in seabirds. Using a state-of-the-art ocean dr...

twentieth century had faced considerable increase in crops yields. nonetheless, it is postulated that world population will reach 10.4 billion until 2050 which means the demand for agricultural crops production should be increased between 60 and 110 percent. in the present study, improvements in grain yields of wheat, maize and rice during the recent decades in iran were studies through analyzi...

this research aimed to assess factors of water quality in ponds l. vannamei in site of bushehr helle and provide solutions to improve water quality shrimp l. vannamei were conducted in this area, during the period of 120 days. this studies was conducted across the 7- hectare pond with a density of 22 shrimp per square meter in breeding site of bushehr helle in 2013. from parameters of water oxy...

Previous work has shown (Bissonnette, 1932) that added electric light after dusk has a pronounced stimulatory influence on the anterior pituitary (Hill & Parkes, 1933), causing the onset of oestrus in the ferret during the non-breeding season of the year from September to March. Marshall (1940) also showed that the time of the onset of the breeding season caused by exposure to light varied with...

—Studies on breeding biology in Neotropical birds are crucial for understanding different aspects of their life histories and also for their conservation. We describe the nesting biology of the Red-crested Cardinal (Paroaria coronata) in central Argentina, a common suboscine that inhabits south temperate forests. We monitored 367 nests from October to February 2005–2008. Nest initiation followe...

The cytokine interleukin-6 (IL-6) mediates a wide range of inflammatory and immune responses. Tumor Necrosis Factor α (TNF-α) has a myriad of pro-inflammatory effects on the skin. Nuclear factor κB (NF-κB) is a transcriptional factor that regulates a battery of genes that are critical to immune system. In this study, we investigated the localizations and expression levels of IL-6, TNF-α and NF-...

Ten years of calving records were examined from Bos taurus crossbred cows (mean of 182 cows/yr) to quantify the effects of environmental conditions during the breeding season on pregnancy rate. Estimated breeding dates were determined by subtracting 283 d from the calving date. Relationships were determined between the proportion of cows bred during the periods from the beginning of the breedin...