The prevalence of keel bone damage as well as external egg parameters of 2 pure lines divergently selected for high (H) and low (L) bone strength were investigated in 2 aviary systems under commercial conditions. A standard LSL hybrid was used as a reference group. Birds were kept mixed per genetic line (77 hens of the H and L line and 201 or 206 hens of the LSL line, respectively, per pen) in ...

Most Lophiiformes including Lophius species are considered to spawn egg masses called an “egg veil” or ribbon” composed of numerous mucoid chambers. However, eggs have been rarely collected in the field and thus little is known about their biological features. Here we examined embryonic development litulon also effects water temperature on from veils field. Embryonic was observed late cleavage ...

Abstract Hydropower is considered an important form of renewable energy, often involving hydropeaking. While the effects hydropeaking on aquatic communities in areas downstream dam are well understood, there a lack studies investigating potential impacts tributaries located further upstream. In this study, we tested operations upstream restored area Danube River, with focus periods backlog and ...

Three White Leghorn strains, their two-way crosses, and two commercial lines were used to study the effects of aging on several parameters related to performance of fitness and nonfitness traits during the first laying cycle of hens housed three per cage. Egg number of the survivors (EPF) and egg number including mortality and morbidity (EPM) were divided into 12 periods of 28 d each, starting ...

Zooplankton demographics operate over multiple time scales corresponding to pelagic parthenogenetic generations, an overwintering stage, and an ‘‘egg bank.’’ Comparisons of pelagic birth and death rates with seasonal diapausing egg production provide insights into local species persistence. The spiny cladoceran (Bythotrephes) possesses morphological adaptations (spines and thick-walled diapausi...

In cage-free egg production systems, concerns have been raised over hen mortality rates. High mortality is an obvious indicator of poor welfare, and problems should be addressed without delay. It is important to note, however, that mortality can vary substantially between hen flocks, and that some cage-free systems have healthy flocks that do not suffer substantial death losses. These systems c...

<p><strong>Background. </strong>Poultry production is a tool for livelihood improvement and poverty alleviation in the developing countries. Indigenous chickens are numerous but lower egg performance than exotic Ethiopia. <strong>Objective</strong>. To compare yield, feed conversion ratio (FCR), mortality, quality traits of Normal feathered local (LL), Sasso-RIR (S...

In this study, the effects of abrupt temperature change on the hatching success and larval survival of eggs, yolk-sac larvae (YSL) and larvae above nest (LAN), for both largemouth bass Micropterus salmoides and smallmouth bass Micropterus dolomieu were quantified. Temperature had a significant effect on hatching success and time to 50% mortality, with large heat shocks causing accelerated morta...