A cage-related foot pad dermatitis in dwarf and normal-sized single comb white Leghorn layers

Footpad dermatitis in broiler chickens in Japan

The prevalence of footpad dermatitis (FPD) in broiler chickens in Japan was investigated. In the first examination at slaughterhouses, lesions were commonly observed on the footpads of a total of 8,985 broiler chickens from 45 flocks on 36 farms. In 3 flocks, all the birds examined had lesions. In the other 42 flocks, the incidence of FPD ranged from 31.9% (81/254) to 99.5% (1/222). The footpad lesions were classified into 4 categories according to the severity of dermatitis as follows; score 0, 1,181 birds (13.1%); score 1, 2,992 birds (33.3%); score 2, 3,000 birds (33.4%); and score 3, 1,812 birds (20.2%). The mean scores of the flocks varied widely from 0.31 to 2.69. Males had higher mean scores than females. No significant differences were found between the mean scores of birds reared in windowless houses and those in open-sided houses. On 4 farms, the investigation was carried out in different seasons, and 3 of them showed higher mean scores in winter than in summer. Next, observation of 2,255 birds from 15 flocks on 5 farms during a 4-week rearing period revealed that FPD was already produced at 7 days of age and worsened with age.

Influence of perches and footpad dermatitis on tonic immobility and heterophil to lymphocyte ratio of chickens

The purpose of the present study was to analyze the effect of perches and footpad dermatitis on stress and fear levels of chickens. In experiment 1 heterophil to lymphocyte ratio and tonic immobility duration were measured in 36-wk-old hens (36 birds) from 2 Spanish breeds of chickens (Black Menorca and Quail Castellana) housed in pens with or without perches from 20 wk of age. There was a significant difference in the heterophil to lymphocyte ratio between perch treatments (P < 0.05), the ratio of hens with perches being lower than that of hens without perches. Hens with perches had significant lymphophilia (P < 0.05). There was no significant difference for the duration of tonic immobility between hens with or without perches. Thus, hens with perches were less stressed than hens without perches, as indicated by the heterophil to lymphocyte ratio. Heterophil to lymphocyte ratio and heterophil number for Black Menorcas were significantly smaller (P < 0.001) than for Quail Castellanas, whereas lymphocyte number was greater in Black Menorcas. The Black Menorca hens had significantly (P < 0.01) shorter tonic immobility duration. In experiment 2 heterophil to lymphocyte ratio and tonic immobility duration were measured in 52-wk-old cocks (36 birds) of each of two different Spanish breeds of chickens (Black Barred Andaluza and Red Barred Vasca) housed in cages from 36 wk of age and showing or not showing footpad dermatitis. There was no significant effect of footpad dermatitis on the heterophil to lymphocyte ratio, its numerator, or its denominator, whereas there was significant effect on tonic immobility duration (P < 0.05) with tonic immobility of cocks with footpad dermatitis being longer than that of cocks without footpads. Thus, cocks with footpad dermatitis were more fearful than cocks without footpad dermatitis, as indicated by the tonic immobility duration. Heterophil to lymphocyte ratio and heterophil number were significantly smaller (P < 0.05) for Black Barred Andaluzas than for the Red Barred Vascas.

Wet litter and perches as risk factors for the development of foot pad dermatitis in floor-housed hens

1. An experiment was conducted to determine whether different moisture levels of litter and perches with different hygienic conditions are involved in the manifestation of foot pad dermatitis in White Leghorn layers. 2. Four different treatments were compared: dry litter and dry perches; dry litter and wet perches; wet litter and dry perches; and wet litter and wet perches. Temperature, pH, air humidity and ammonia changes in the pens were monitored. 3. The mean prevalence of foot pad lesions in groups 1, 2, 3 and 4 was 17%, 13%, 49% and 48% respectively. The overall incidence of foot pad lesions in birds reared on dry litter was 38%, and in birds reared on wet litter 92%. 4. When the air temperature was above 20 degrees C, an increasing moisture content in the litter was associated with an increasing incidence of foot pad dermatitis. However, when the air temperature was below 20 degrees C there were no new cases of dermatitis in any of the 4 treatments. There were no significant differences in litter pH or ammonia between the 4 treatments when compared over the whole experiment. 5. Although the incidence of lesions was not significantly affected by the presence of wet perches, the area of the lesions tended to be in groups with wet patches than in groups with dry perches. 6. It is suggested that moisture and temperature are important contributing factors for the occurrence of foot pad dermatitis in laying hens. Wet perches may contribute to the severity of such lesions.

Behavior, production, and well-being of the laying hen. 1. Effects of movable roosts, relationship of cage mates, and genetic stock

The effects of movable roosts, relationship of cage mates (siblings versus nonsiblings), and genetic stock on measures of behavior, production, and physical condition were investigated. Sibling and nonsibling pairs of hens derived from two male parental stocks (designated MPS1 and MPS2) were randomly assigned to two cage batteries (384 hens total). The batteries were identical except that the cages of one had individual wood roosts, which were automatically raised at night and lowered the next morning. The laying phase comprised 13 28-day periods. On the first 4 days of Periods 1, 3, 5, 7, 9, and 11, video recordings were made of 8 cages per day. Video-recorded data for Period 5 were discarded, however, because equipment failure caused an unplanned photoperiod ratio. Direct visual observations were carried out in Period 13. Egg production and feed consumption were recorded in each period. Feather scores were determined in Periods 3, 6, 9, and 12, and in Periods 6 and 13, hens were weighed and the number of lesions to the feet counted. Overall, roosts appeared to improve well-being. Resting occurred more in cages with roosts, feathering was better initially, body weights were slightly higher, and foot lesions were were fewer. Egg production was not affected except that egg cracks were more frequent in roosts cages. Relationship of cage mates had relatively little influence. However, in conventional cages, nonsiblings manifested more bobbing behavior, and in MPS1, nonsiblings had higher feed consumed per dozen eggs. Hens of MPS1 performed more head flicking, drinking, physical displacement, aggression, and cage wall climbing than MPS2 hens. They also had higher egg production, weaker egg shells, poorer feathering, and more lesions to the feet. The genetic stock differences suggest that hens of MPS1 experienced poorer well-being. None of the treatments significantly affected mortality.