Both density-dependent factors and environmental stochasticity can impact the dynamics of free-ranging populations. The pathways through which these factors influence population dynamics can be complex and may be immediate or lagged, and cumulative effects of environmental factors have been reported. We examined the effects of the severity (snow depth and persistence and winter rainfall) of the...

Body morphology of juvenile Chinook salmon Oncorhynchus tshawytscha in the upper Willamette River, Oregon, U.S.A., was analysed to determine if variation in body shape is correlated with migratory life-history tactics followed by juveniles. Body shape was compared between migrating juveniles that expressed different life-history tactics, i.e. autumn migrants and yearling smolts, and among parr ...

Two complementary methods, namely Multi-Trait Meta-Analysis and Versatile Gene-Based Test for Genome-wide Association Studies (VEGAS), were used to identify putative pleiotropic genes affecting carcass traits in Bos indicus (Nellore) cattle. The genotypic data comprised over 777,000 single-nucleotide polymorphism markers scored in 995 bulls, and the phenotypic data included deregressed breeding...

Prevalence of antibodies to Neospora caninum was determined in a cross-sectional consensus survey of 1029 bovines in a dairy herd with endemic Neospora-induced abortion. Sera were screened by indirect fluorescent antibody test (IFAT). The prevalence of N. caninum antibody in the IFAT was 17.9% in 107 neonates, 26.2% in 233 yearling heifers and steers, 39.07% in 218 mature heifers, and 26.9% in ...

The effect of growth rate from birth through 30 months of age on the reproductive performance of Polled Hereford heifers calving as 2-year-olds was examined. Heifers with high gains during the first winter as weanlings had higher breeding efficiency when bred as yearlings, had larger pelvic areas as 2-year-olds, gave birth to larger calves, had less calving difficulty at first parturition and h...

to study the fleece characteristics of native goats in sistan and balouchestan province, fiber sample was taken from 270 females between one to three years old from khash, saravan and iranshahr cities. the differences between age groups for all fleece parameters except fleece weight were not significant. the fleece weight of two and three years old goats were 263.4 (± 7.7) and 315 (± 7.8) gr, r...

the present study was performed to evaluate the on-station growth performance of local and dorper × local crossbred sheep in eastern amhara region, ethiopia. data on 302 lambs collected over a 4-year period (2009 to 2012) on local and dorper × local crossbred sheep at sirinka breeding, evaluation and distribution site were used in this study. fixed effects considered were breed, lamb sex, birth...

The objective of this study was to estimate genetic parameters for real-time ultrasound measurements of longissimus muscle area (LMA), 12th rib backfat thickness (FT), percent intramuscular fat (IMF), and yearling weight (YW) for 1,299 yearling Brangus bulls and heifers. A single ultrasound technician performed all measurements. The number of observations was 1,298, 1,298, 1,215, and 1,170 for ...

Understanding the habitat requirements of salmonids in streams is an important component of fisheries management. We examined the summer and autumn habitat use of yearling Rainbow Trout Oncorhynchus mykiss in relation to available habitat in two streams in the Lake Ontario watershed. Little interstream variation in trout habitat use was observed; the variation that did occur was largely due to ...