Stopped-flow fluorescence and circular dichroism spectroscopy have been used in conjunction with quenched-flow hydrogen exchange labelling, monitored by electrospray ionization mass spectrometry, to compare the refolding kinetics of hen egg-white lysozyme at 20 degrees C and 50 degrees C. At 50 degrees C there is clear evidence for distinct fast and slow refolding populations, as observed at 20...

Feather pecking and cannibalism in farm-kept laying hens are damaging behaviors both in terms of animal welfare and economic loss, and a major challenge in modern poultry farming. Both rearing with a foster hen and genetic selection have been demonstrated to reduce feather pecking in laying hens. We examined the effects of rearing with a foster hen, genetic selection for low mortality from cann...

background:avian intestinal spirochetosis (ais) is causedby spiral-shaped gram-negative brachyspira spp. in poultry. it isknown as a cause of diarrhea, low egg production, and increasedoccurrence of dirty eggs in layer hens. objectives: in this study,the presence of some brachyspira spp. was investigated in layinghens. methods: a total of 100 cloacal swab samples wereindividually collected from...

When the nucleus of a hen erythrocyte is introduced into the cytoplasm of a human or mouse cell in culture, it resumes the synthesis of RNA. The reactivated erythrocyte nucleus undergoes great enlargement, but it does not, for at least 2 or 3 days, develop nucleoli which can be discerned under the light microscope. During this period, the heterokaryon, although it may contain several active ery...

In this study, we expand on the examination of genetically determined differences in host responses that correlate with clearance of Chlamydia trachomatis from the genital tract. We infected C57BL/6, BALB/c, and C3H/HeN mice with the mouse pneumonitis agent of C. trachomatis (MoPn). C57BL/6 mice had the shortest course of infection (22 days) and the lowest incidence of severe hydrosalpinx. BALB...

OBJECTIVE Study of the hen immune system led to seminal contributions to basic immunological principles. Recent studies of spontaneous ovarian cancer in the laying hen show strikingly similar tumor types and antigen expression compared to human ovarian cancer, suggesting hens would be valuable for studies of tumor immunology and pre-clinical vaccine development. Circulating mesothelin is a rela...

Agriculture accounts for 10 to 12% of the World's total greenhouse gas (GHG) emissions. Manure management alone is responsible for 13% of GHG emissions from the agricultural sector. During the last decade, Québec's egg production systems have shifted from deep-pit housing systems to manure belt housing systems. The objective of this study was to measure and compare carbon dioxide (CO₂), methane...

Under Council Directive 1999/74/EC, minimum space allowances per laying hen range from 550 cm(2) in unfurnished cages to 1111 cm(2) in alternative housing, and to 40,000 cm(2) outdoors for free-range hens. In official reports on the welfare of laying hens, there is recognition that knowledge of their space requirements is inadequate. This experiment studied expression of behaviour, including sp...

This study examined the long-term effects of housing system on several aspects of laying hen production. At 19 wks of age, 336 White Leghorn hens were placed, 3 birds per cage, into battery cages; 437 birds were assigned to an aviary with communal nests, ambulation areas, and three raised tiers with feeders and drinkers. Family groups were split between the two housing systems. The hens were ho...

an eight week study was conducted to investigate the effect of inclusion of tomato waste meal in layer diets on laying performance, egg quality and lipid profile as a means to reduce feed cost and pollution. four laying diets containing tomato waste meal (twm) at four levels of 0, 3, 6 or 9% were assigned randomly to 4 groups of 40 birds divided among four replicates of 10 birds in each dietary...