The bacterium Erysipelothrix rhusiopathiae can infect a wide range of mammals (including humans) and birds. Disease outbreaks (erysipelas) have been considered unusual in chickens internationally, but outbreaks with high mortality and egg production losses have been diagnosed in Swedish laying hen flocks every year since 1998. Different aspects of E. rhusiopathiae infection in chickens were exa...

Free range systems can improve the welfare of laying hens. However, the access to environmental resources can be partially limited by social interactions, feeding of hens, and productivity, can be not stable and damaging behaviors, or negative events, can be observed more frequently than in conventional housing systems. In order to reach a real improvement of the hens' welfare the study of thei...

n the ’70s fixed-to-fixed microwave links were developed and deployed. Wireless local loop (WLL) systems could also have been implemented in the ’70s in U.S. rural areas, but were not. The cost justifications at that time for WLL were: For the Near Term — Using the radio link for WLL was the solution because the cost of laying a long wire cable to connect to a remote point was very high. For th...

Most animals reproduce seasonally. They time their reproduction in response to environmental cues, like increasing photoperiod and temperature, which are predictive for the time of high food availability. Although individuals of a population use the same cues, they vary in their onset of reproduction, with some animals reproducing consistently early or late. In avian research, timing of reprodu...

Drosophila melanogaster egg-laying site selection offers a genetic model to study a simple form of value-based decision. We have previously shown that Drosophila females consistently reject a sucrose-containing substrate and choose a plain (sucrose-free) substrate for egg laying in our sucrose versus plain decision assay. However, either substrate is accepted when it is the sole option. Here we...

This experiment was conducted to evaluate the effects of different levels of dried aerial parts powderand extract of pennyroyal­ (Mentha pulegium) medicinal plant on performance, egg traits, blood biochemical and immunity parameters of laying hens. Two-hundred-fifty-two Hi-line (W36 strain) laying hens from 46 until 58 weeks of age were used in a completely randomized design in 7 treatments and...

The population of great hornbills (Buceros bicornis) in the United States is rapidly aging, and captive breeding efforts have not met population managers’ expectations for a sustainable captive group. Little is known about the reproductive physiology of these birds. This study reports the first data on the reproductive endocrinology of the great hornbill. The hormone profiles of the only pair o...

an experiment was conducted to evaluate the effects of different levels of mineral and vitamin premix on performance and egg traits of laying hens from 37 to 49 weeks of age. two hundred and forty laying hens (hy-line w-36 strain) were randomly assigned to 5 dietary treatments of four replicates each with 12 hens per replicate). the levels of mineral and vitamin premixes in the experiment were ...

Heat stress in laying hens is prompted by combinations of environmental temperature and humidity that prevent the bird’s thermoregulatory process from effectively dissipating the heat produced during metabolism [32]. High environmental temperature is the major problem faced by laying hens as well as poultry farmers usually in summer months. The ideal temperature for laying hens is about 20°C [2...

We investigated the relationship between plasma and yolk oestrogens in laying female zebra finches (Taeniopygia guttata) by manipulating plasma oestradiol (E2) levels, via injection of oestradiol-17beta, in a sequence-specific manner to maintain chronically high plasma levels for later-developing eggs (contrasting with the endogenous pattern of decreasing plasma E2 concentrations during laying)...