Parental investment in eggs and, consequently, in offspring can profoundly influence the phenotype, survival and ultimately evolutionary fitness of an organism. Avian eggs are excellent model systems to examine maternal allocation of energy translated through egg size variation. We used the natural range in emu Dromaius novaehollandiae egg size, from 400 g to >700 g, to examine the influence of...

Two experiments were conducted to determine the effects of micronization (infrared heat treatment), dehulling, or enzyme supplementation on the nutritive value of three cultivars (Impala, Radley, and Sirius) of peas in laying hens. In Experiment 1, 280 White Leghorn hens were fed diets containing micronized and dehulled peas for a period of 12 wk. The dietary inclusion of peas was 600 g/kg (cor...

Although the effects of POPs on the health of free ranging loggerhead sea turtles (Caretta caretta) has been well investigated (Keller et al. 2004; Keller et al. 2006a; Keller et al. 2006b), there was only one previous study on the toxicological effects of POPs on sea turtle embryonic development (Podreka et al. 1998). However, there are a number of studies on freshwater turtles that have inves...

The objectives of this experiment were to investigate effects of dietary replacement of maize with bakery by-product (BB) with or without enzyme supplementation on the performance of laying hens and egg quality characteristics. A total number of one hundred and eighty 87-week-old Hy-Line Leghorn hens, with an average laying rate of 56.7±3.8% (late production phase) and 1470±14 g live body weigh...

The smooth softshell Apalone mutica is a North American trionychid turtle typically found in moderate to fast moving rivers and streams. Such habitats contrast with more resource rich environments (e.g., marshes and swamps) inhabited by other turtle species for which parental investment and egg and hatchling components have been studied. We measured components of eggs, embryos, and hatchlings a...

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 ...

Body mass was measured in Marbled Murrelets Brachyramphus marmoratus from May to August, 1994–1998 at Desolation Sound, and during June and July 1997 at Mussel Inlet, British Columbia, Canada, to assess seasonal, sexual, site and intra-annual variation. Birds were captured by mist-net, and by night-lighting, and were sexed using molecular techniques. The breeding status of females (gravid or no...

Ammonia (NH3) emissions from laying hens are affected by nutrient content of the diet, manure quantity, and manure properties such as moisture content, nitrogen content, and pH. These production traits may vary with strain of the hen. However, limited information is available concerning the effects of laying-hen genetics on manure properties and NH3 emission. This study was conducted to compara...

The present research was designed to examine the genetic analysis of egg weight, egg yolk weight and egg albumen weight of Bovan Neva Black laying hens at 25, 51 and 72 weeks. For this purpose, thirty birds were selected from the layer flock in the Babcock University Teaching and Research Farm. They were individually housed in separate labeled battery cage. A total of thirty eggs were collected...