نتایج جستجو برای: laying hens

تعداد نتایج: 15944  

Journal: :Applied animal behaviour science 2000
Olsson Keeling

Free-living hens roost on branches in trees at night, and laying hens in aviary systems or cages provided with perches also make extensive use of these for night-time roosting. It is therefore suggested that roosting on perches is important to the hens and that domestic hens should be provided with perches in order to promote welfare. However, no study has addressed the question of motivation f...

Journal: :Poultry science 2010
M M van Krimpen T Veldkamp G P Binnendijk R de Veer

An experiment was performed to investigate the effect of animal vs. vegetable protein sources in the diet of laying hens on the development of hen performance. A diet containing protein sources of only vegetable origin was compared with 4 diets, each containing 1 of 4 processed animal proteins (PAP). Two PAP (Daka-58 and Sonac-60) were classified as meat meals, and the remaining 2 (Daka-40 and ...

Journal: :Poultry science 2010
E R Dickey K Bregendahl K Stalder R Fitzgerald A K Johnson

The objectives of this study were to compare the behaviors, postures, and heterophil-to-lymphocyte ratios (H:L) of laying hens housed in a cage system when offered a Ca premolt treatment and low-energy molt diets vs. a traditional feed withdrawal (FW) treatment during and after molt. A total of 144 Hy-Line W-36 hens (85 wk of age), housed 3 hens/cage (413 cm(2)/hen), were used. Hens were allott...

Journal: :Poultry science 1999
S R Caldwell A F Johnson T D Yule J L Grimes M Ficken V L Christensen

Juvenile turkey hens were actively immunized against vasoactive intestinal peptide (VIP) prior to photostimulation to evaluate its effect on enhancing egg production. VIP antibody titers were generated in the VIP immunized hens and a greater rate of egg production per hen was observed compared to controls. In addition, the first egg laying cycle was extended for an additional 7 wk without a sig...

2012
MAF Nasr J Murrell LJ Wilkins CJ Nicol

A majority of laying hens fracture their keel bones during the laying cycle. It is not easy for a farmer to identify hens with fractures and hen survival rate seems high. Thus, the effect of both recent and healed fractures on bird welfare is unclear. We aimed to investigate the impact of these keel-bone fractures on hens’ production and behaviour. The egg production, mobility and behaviour of ...

Journal: Poultry Science Journal 2016

In this experiment, the effects of fennel and thyme extracts with and without flaxseed were investigated on performance and egg quality of Leghorn-type laying hens (Hy-Line W-36). 200 laying hens from 26 to 38 weeks of age were assigned to five dietary treatments with five replications. The treatment groups were: 1) Control (a diet without any additives); 2) control diet plus fennel (40 mg/kg f...

Journal: :Physiology & behavior 2013
Marjolein S Kops Elske N de Haas T Bas Rodenburg Esther D Ellen Gerdien A H Korte-Bouws Berend Olivier O Güntürkün J Elizabeth Bolhuis S Mechiel Korte

Severe feather pecking (SFP) in laying hens is a detrimental behavior causing loss of feathers, skin damage and cannibalism. Previously, we have associated changes in frontal brain serotonin (5-HT) turnover and dopamine (DA) turnover with alterations in feather pecking behavior in young pullets (28-60 days). Here, brain monoamine levels were measured in adult laying hens; focusing on four brain...

2010
H. I. Al - Sadi E. Y. Hussein

The purpose of this study was to evaluate cytologically the bone marrow (and peripheral blood) of adult laying hens affected with lymphoid leukosis. Diagnosis of the neoplasm was made on the basis of clinical history, signs and symptoms and pathology. Only histologically confirmed cases were included in the study. Examination of blood smears revealed +2 heterophil toxicity and the presence of l...

2017
Shafiqur Rahman Hongwei Xin Stacey A. Roberts James A. Arthur Robert T. Burns

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...

2014
Susie E Hewlett Elly C Zeinstra Frank JCM van Eerdenburg TB Rodenburg Peter JS van Kooten FJ van der Staay Rebecca E Nordquist

BACKGROUND Feather pecking and cannibalism are major concerns in poultry farming, both in terms of animal welfare and farm economics. Genetic selection and introduction of (aspects of) maternal care have been suggested as potential interventions to reduce feather pecking in laying hens. Altered brain development has been proposed to reflect welfare states in animals, and can provide more insigh...

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