Footpad Dermatitis In Broilers Research Articles

Automatic Scoring System for Monitoring Foot Pad Dermatitis in Broilers

The assessment of foot pad dermatitis at slaughter is a suitable method to assess and monitor the welfare of broilers. The goals of this study were to define and validate a camera-based score that could identify macroscopic lesions of the foot pads, to identify errors, and to assess possible external factors that could influence the assessment. In the first phase 200 feet of broilers and in the second phase 500 feet were collected at slaughter, assessed visually, hung back into the evisceration line, and assessed by an automatic system. The camera score cut-off values were defined in the first (=calibration) phase. In the second (=validation) phase, the performance of diagnosis for these cut-off values was evaluated, and possible errors in the assessment of reference surface area and foot pad lesions were analyzed. The results showed that, in particular, Macro Scores 0, 2, and 3 could be identified with sufficiently high sensitivity. For Macro Score 1, the sensitivity of diagnosis was not sufficiently high in the two evaluated software versions. The current automatic assessment systems at slaughter could be adjusted to the cut-off values in order to classify foot pad dermatitis lesions. Furthermore, software updates can enhance the performance measures and lower the probability of errors.

홰 종류 및 높이 설정에 따른 육계 생산성, 행동특성, 계육품질에 미치는 영향

This study investigates the effect of perch type and height on the growth performance, footpad dermatitis (FPD), blood parameters, behavioral characteristics, and meat quality of broilers. A total of 912 one-day-old male Ross 308 broilers (48.23± 0.264 g) were subjected to a three x two factorial design of three types of perch (wood, steel, plastic) and two levels of perch height (10→30 cm change, 10 cm fixed) over a five-week experiment. Growth performance, perch availability, litter quality, FPD incidence, serum biochemical parameters, and meat quality of the broilers were evaluated. There were no significant differences in the body weight, feed conversion ratio, and biochemical parameters (except for aspartate aminotransferase), pH, color, and water holding capacity. The incidence of FPD was significantly higher in the plastic perch group than in the wood and steel perch groups (<i>P</i>&lt;0.05) at five weeks of age. Perch use was high in the order of wood, steel, and plastic groups in the daytime and nighttime at one, three, and five weeks of age (<i>P</i>&lt;0.05). Perch use was higher in the 10 cm fixed group than the 10→30 cm group (<i>P</i>&lt;0.05). The shear force of the breast significantly increased in the order of wood, steel, and plastic groups (<i>P</i>&lt;0.05). In conclusion, the group with a fixed perch height of 10 cm had high perch usage. Additionally, the use of wooden perches was higher than that of other materials, and it lowered the incidence of FPD in broilers.

Orange corn diets associated with lower severity of footpad dermatitis in broilers

Footpad dermatitis (FPD), damage and inflammation of the plantar surface of the foot, is of concern for poultry because FPD affects the birds' welfare and production value. Footpad dermatitis is painful and causes costly chicken paw downgrades, carcass condemnations, and reduced live weights. However, a universal preventative has not been found. The hypothesis was that diets containing orange corn, when compared with diets containing yellow or white corn, would reduce the severity of footpad dermatitis in broiler chickens on wet litter. When compared with yellow and white corn, orange corn contains higher quantities of carotenoids, antioxidant pigments, believed to play a role in skin and feather health. This experiment was a randomized block, 3 × 2 factorial design: orange, yellow, and white corn diets with birds raised on wet or dry litter (control group). Female Ross 708 broilers (n = 960) were used to create 4 replicates of each diet x litter treatment combination. Footpads were scored at day 19, 27, 35, and 42, following the Global Animal Partnership standard's 0–2 scale of visual increasing severity: 0 indicates minimal damage and 1 and 2 indicate mild to severe lesions and ulceration, dark papillae, and/or bumble foot. At 42 d of age, birds on the wet litter had greater severity of FPD, scores 1 and 2, compared with the control group (88 vs. 13% respectively; P < 0.0001). At 42 d of age, prevalence of more severe footpad scores, 1 or 2, was lowest on the orange corn diet (33%), followed by white corn (56%) and yellow corn (63%). Birds fed the orange corn diet had higher BW throughout the study (P = 0.004) and had fat pads and livers with higher yellow pigment deposition (P < 0.005). Litter moisture content altered microbiome composition but corn type did not. In conclusion, the main determinant of FPD in this study was exposure to wet litter. When compared with yellow and white corn, orange corn was associated with improved bird growth and reduced severity of footpad dermatitis, especially at later time points.

Zinc oxide nanoparticles prevent multidrug resistant Staphylococcus-induced footpad dermatitis in broilers

ABSTRACT The current experiment was designed to evaluate the effects of dietary supplementations of zinc oxide nanoparticles (ZONPs) on some behavioural, performance, welfare and histopathological changes in broilers exposed to multidrug resistant Staphylococcus aureus (MRSA)-induced footpad dermatitis (FPD). Eighty-four male Indian River (IR) broilers were randomly allotted to six different dietary treatments as follows: C−ve, C+ve, 10, 20, 30 and 40 ppm ZONPs from 7 to 49d of age. At day 28, broilers (n = 70) were sub-cutaneously injected with 0.5 ml of saline containing 5.3 × 107 CFU/ml of S. aureus (MRSA) in each metatarsal foot pad. Control (non-infected) broilers were given 0.5 ml of saline (n = 14). Results clarified that non-infected birds and ZONPs-fed birds had significantly higher standing and feeding activities and lower resting activities in comparison with the infected group. Also, the S. aureus infected group had significantly lower body weight gain (BWG) and higher feed conversion ratio (FCR) than the non-infected group. In addition, the non-infected birds and ZONPs groups had significantly lower object crossing and tonic immobility times (TI) and gait scores (GS) in comparison with the S. aureus group. Only ZONPs 30, 40 ppm and non-infected groups had a significantly higher latency to lie time (LLT) and lower serum cortisol level in comparison with the S. aureus group. Moreover, there were significant changes in the gross lesion score and histopathological lesions between the different groups. In conclusion, the dietary supplementation of ZONPs can reduce S. aureus-induced negative effects of FPD in broilers.

Effect of humate supplementation to feed and/or litter on performance, intestinal viscosity, litter quality, and occurrence of footpad dermatitis in broilers fed barley-based diets.

We investigated the effect of in-feed and/or in-litter supplemental humate against footpad dermatitis (FPD) in broilers fed diets based on barley. Three hundred and sixty 1-day-old Ross 308 broiler chickens were randomly distributed to 24 floor pens (4 treatments, each consisting of 6 replicate pens; 15 chickens per pen) as a completely randomized design with 2 × 2 factorial arrangement of two levels of supplemental humate in feed (0 and 1g/kg feed) and litter (0 and 5g/kg litter). Growth performance, intestinal viscosity, litter quality, and incidence and severity of FPD in broilers were measured. In addition, malondialdehyde (MDA) and superoxide dismutase (SOD) levels were determined in blood and footpad tissues of broilers with different FPD scores. The results revealed that there was no interaction between humate supplementation to feed and litter. Neither dietary nor litter supplementation of humate had a significant effect on growth performance, intestinal viscosity, litter quality, and occurrence of FPD. And also, MDA and SOD levels in serum and footpad tissue did not affect by either dietary or litter supplementation of humate. The presence of FPD (score 1) had no effect on MDA and SOD levels in serum, however, increased the MDA and SOD levels (P < 0.001, P = 0.001, respectively) in footpad tissue of broilers. The intestinal viscosity did not differ between FPD scores 0 and 1. In conclusion, findings of this experiment suggest that humate supplementation to feed and litter did not alleviate FPD development in broilers fed diets based on barley. In addition, the presence of FPD lesions increases the MDA and SOD levels in the footpad tissues.

Differential Effects of Dietary Methionine Isomers on Broilers Challenged with Acute Heat Stress.

In this study, we investigated the effect of methionine isomers (D- and L-methionine) on growth performance, blood metabolite levels, nutrient digestibility, intestinal morphology, and foot pad dermatitis in broilers challenged with acute heat stress. In total, 240 broilers were randomly allocated in a 2×2 factorial arrangement consisting of two dietary treatments (D- vs. L-methionine) and two thermal environmental conditions (thermo-neutral vs. acute heat stress). Methionine isomers were added to the diet as an ingredient according to the diet formulation. The broilers were exposed to acute heat stress at 33°C for 5 h on day 14. The average daily gain and feed conversion ratio of birds fed L-methionine were higher than those fed D-methionine (P<0.05) from the time of hatching till 21 days. Induced acute heat stress impaired (P<0.05) the daily gain and feed intake of the broilers on day 21. Furthermore, the blood urea nitrogen levels of birds subjected to acute heat stress on days 14 and 21 were higher (P<0.05) than those of their counterparts. Longer villi (P<0.05) were observed in broilers fed L-methionine-supplemented diet than in those fed D-methionine-supplemented diet on day 14, irrespective of thermal environmental conditions. Heat stress reduced (P<0.01) nutrient digestibility of the broilers on days 14 and 21. Higher incidence and severity of foot pad dermatitis were observed (P<0.05) in broilers fed diet containing D-methionine than in those fed L-methionine-supplemented diet. In conclusion, L-methionine-supplemented diet improved growth performance, overcame growth depression, and reduced the incidence of foot pad dermatitis when broilers were exposed to acute heat stress in the starter period.

Supplemental boric acid does not prevent the development of footpad dermatitis in broilers subjected to high stocking density

The present study was conducted to evaluate the protective effect of dietary boric acid supplementation on the development of incidence and severity of footpad dermatitis (FPD) in broiler chickens subjected to normal or high stocking densities (NSD or HSD). A total of 576 1-day-old ROSS 308 broiler chickens were randomly allocated to 4 treatments (8 replicate pens per treatment) in a 2 × 2 factorial arrangement of dietary boric acid (0 and 60mg/kg) and stocking density (NSD 14 birds/m2 and HSD 22 birds/m2). Basal diets were formulated for starter, grower, and finisher phases. Growth performance, litter quality (litter pH, moisture, temperature, and NH3 volatilization), serum and litter boron levels, and incidence and severity of FPD were recorded. The HSD affected the body weight gain and feed intake of broiler chickens during all phases and 0 to 42 (P < 0.05), whereas feed conversion ratio (FCR) was poor at 0 to 21 days only. Dietary boric acid had no effect on the growth performance of broiler chickens. Litter pH, moisture, and NH3 volatilization were higher in broiler chickens subjected to HSD (P < 0.05). Thus, the incidence and severity of FPD increased in response to HSD (P < 0.05). Dietary boric acid reduced the litter pH and NH3 volatilization on day 42 of experiment (P < 0.05). However, dietary boric acid supplementation had no effect on the incidence and severity of FPD. Boric acid supplementation in broiler diets increased the serum and litter boron levels at day 42 in broiler chickens subjected to NSD or HSD (P < 0.05). In conclusion, HSD resulted in poor growth performance, litter quality, and greater incidence and severity of FPD in broiler chickens. Dietary boric acid was ineffective against FPD in broiler chickens although it improved the litter quality by lowering the litter pH and NH3 volatilization.

Impact of different dietary protein sources on performance, litter quality and foot pad dermatitis in broilers

1. Abd El-Wahab A., Beineke A., Beyerbach M., Visscher C.F., Kamphues J., 2011. Effects of floor heating and litter quality on the development and severity of foot-pad dermatitis in young turkeys. Avian Dis. 55, 429–434, https://doi.org/10.1637/9684-0.... CrossRef Google Scholar

Effect of Pelleted and Chopped Wheat Straw on the Footpad Dermatitis in Broilers

Effect of Pelleted and Chopped Wheat Straw on the Footpad Dermatitis in Broilers

Impact of Trace Minerals on Wound Healing of Footpad Dermatitis in Broilers

Footpad dermatitis (FPD) is used in the poultry industry as an animal welfare criterion to determine stocking density. Trace minerals (TM) play a role in skin integrity and wound healing. This study evaluated the impact of TM on FPD and consisted of 3 treatments supplemented with 0 (NTM), low (LTM) and high (HTM) TM levels in the same basal diet. On d21, 71% birds in all treatments developed mild FPD and pens were top-dressed with dry litter to promote FPD healing. Compared to NTM, LTM reduced area under the curve (AUC) of FPD lesion scores during d21–42, HTM reduced the AUC of FPD lesion scores during d7–21 and d21–42. LTM improved growth performance on d14, HTM improved growth performance on d14 and d28. LTM and/or HTM increased gene expression of VEGF, TIMP3, TIMP4, MMP13, ITGA2, ITGA3 and CD40, which promoted collagen synthesis, deposition and organization; cell migration, matrix remodeling, and angiogenesis. LTM and/or HTM increased inflammation by upregulating TNFα and IL-1β during the early wound healing phase and reduced inflammation by downregulating IL-1β during the late wound healing phase. Our findings showed that TM not only improved growth performance but also reduced FPD development by promoting FPD wound healing.

Inter-rater agreement in visual assessment of footpad dermatitis in Danish broiler chickens

ABSTRACT1. The performance of the scoring in the Danish footpad dermatitis (FPD) surveillance system was evaluated by determining inter-rater agreement in visual inspection of FPD in broilers between two independent raters (R1 and R2) and the official scoring at a Danish slaughterhouse.2. FPD scores were evaluated in 1599 chicken feet. The two raters and the slaughterhouse scored equal proportions of score 0. So did R1 and R2 when assessing score 1 and the more severe lesion score 2, whereas the slaughterhouse scored a markedly higher proportion of score 1 and a lower proportion of score 2. Aggregated FPD flock scores ranged from 5 to 163 (R1 and R2) and from 8 to 107 (slaughterhouse).3. The level of agreement between the two raters was high for scores 0, 1 and 2 and for flock scores. Agreement between raters and the slaughterhouse was lower when R1 and R2 recorded score 2 than when they recorded scores 0 and 1.4. This study indicates that the occurrence and severity of lesions are underestimated in the official Danish FPD scoring system.

Footpad Dermatitis in Broilers: Differences between Strains and Gender

Pododermatitis, also known as bumblefoot, is an inflammatory lesion of the footpad. The objective of this study was to evaluate the influence of genetic strain and sex on the incidence of footpad lesions in broilers. The experiment was carried out at Sao Paulo State University, using 480 broilers distributed in a completely randomized experimental design in a 2X2 factorial arrangement (2 strains X2 sexes), with four replicates of 30 broilers each, totaling 16 experimental units. Feed intake, weight gain, feed conversion ratio, and livability were evaluated at 21, 35 and 42 days of age; production efficiency factor was determined at the end of the rearing period. On day 42, the footpads of 100 broilers were grossly examined and assigned a lesion score in a 1-3 scale (Almeida Paz & Martins, 2014). Three samples per score within treatment were collected for microscopic evaluation. Analysis of variance was applied and performance parameter means were compared by Tukey's test. Footpad lesion incidence was analyzed by the c2 test using SAS (version8.2). Ross(r) broilers presented higher feed intake during all evaluated periods, and higher weight gain only in the period 1 to 21 days compared with Cobb(r) broilers. On the other hand, Cobb(r) presented better feed conversion ratio in the periods of 1 to 35 and 1 to 42 days. The incidence of foot pad lesions was statistically different (p< 0.05) between strains and sexes, but there were no interactions between these factors. The lesion scores assigned were compatible with the histopathological results, showing that the higher the score, the more severe were the dermal and epidermal lesions.

Effect of straw size and microbial amendment of litter on certain litter quality parameters, ammonia emission, and footpad dermatitis in broilers

Abstract. This study was conducted to evaluate the impact of litter amendment (microbiological product – Micropan complex) and straw size (unchopped and chopped straw) on pH, moisture level, ammonia emission, and footpad dermatitis in broilers. A total of 1200 1-day-old Ross 308 broilers were randomly allocated to four treatments (2 × 2 factorial arrangement), with four replicates per treatment. Each replicate consisted of 75 as-hatched birds per pen. The first factor consisted of wheat straw – chopped (C) or unchopped (U) – and the second factor was the litter amendment with (WM) or without (OM) Micropan® (enzymatic bacterial product – Eurovix, USA). At 4, 5, and 6 weeks of the trial, the levels of ammonia concentration, moisture content, and pH of litter in each pen were measured. The foot pad lesions were evaluated at 21, 35, and 42 days of age. Broilers reared on chopped straw had significantly better leg condition as expressed by a smaller incidence and severity of footpad dermatitis. The pH value of litter was decreased and footpad quality was significantly improved by Micropan application in broilers kept on chopped and unchopped straw in the sixth week of age. There was no significant effect of Micropan application and straw size on ammonia emission in broiler housing.

Study of animal welfare through analysis and comparison of the presence of foot pad dermatitis in broilers raised in controlled environments in Brazil and Spain

The pododermatitis interacts directly with the animal welfare, it is a disease that alters the behavior, causing serious discomfort to the animals and is also a port for incoming pathogens, being the legs constantly on the chickens litter. We collected data of male and female chicken's feet with 14, 28 and 42 days of age, in four negative pressures poultry (A, B, C and D) with controlled temperature, either of the coolers side and of the exhausters side, totaling 144 birds in hot season in Brazil and 144 birds in cold season in Spain, applying an evaluation of injury scores of 1-4. Males and females showed no significant differences in any country, although the media in Brazil were higher. In Spain the aviary A showed higher scores of injuries and in Brazil there was no significant difference in any aviary. Regarding ages, in animals with 28 and 42 days, the lesions were significantly bigger than 14 days in both countries. The scores on hand showed significant differences only for the media in Brazil, which were higher than that of Spain. Being the area of the coolers more wet, this indicates that it may increase the injury index, with the aggravation of the external temperature and relative humidity of the air higher in Brazil. We conclude that the external ambience influences the internal ambience and added to the management and reuse of the litter may interfere in increasing injury score as the birds gain more weight. Keywords : cushion plant lesion, contact dermatitis, negative pressure, ambience.

Influence of the dietary protein level and type of litter on the incidence and severity of footpad dermatitis in broilers

Footpad dermatitis (FPD) is a condition that causes necrotic lesions on the plantar surface of the footpads in broilers, and in severe cases may cause pain. The aim of this study was to determin the influence of tree level of dietary protein and four type of litter on the incidence of the FPD. A total of 1,272 one-day-old chicks were raised on floor pens in a design involving 3 A— 4 arrangement of protein level [high (HP), medium (MP) or low (LP)], and litter materials (whole wheat straw, rice hulls, wood shavings and a mixture of the three types listed above), on a 3-stage feeding program (2 replicate pens/treatment; 50 birds/pen). The incidence and development of FPD were recorded weekly for all birds from day 8 to slaughter. The largest body weight was observed in the HP group (2441.96 g), followed by MP (2308.16 g) and LP (2215.34 g) group. FPD scores for protein level ranged from 53 (LP) to 76 (MP), and for litter type range from 7 (wood shavings) to 150 (whole wheat straw) exceeding the value of 50 points considered by the EU proposal as threshold. The incidences of FPD for protein level were 32% (LP), 48% (MP) and 43% (HP), and 8% (wood shavings), 22% (rice hulls), 52% (mixture) and 80% (whole wheat straw). The results obtained in this study lead to the conclusion that protein level and litter type influences in a great extent the body weight of broiler chickens and FPD score at slaughter .

Genetic parameters of foot-pad dermatitis and body weight in purebred broiler lines in 2 contrasting environments

The aims of this study were to investigate the genetic background of foot-pad dermatitis (FPD) in 4 different broiler lines reared in 2 contrasting environments (pedigree or sib-test) and to evaluate the performance of simultaneous genetic selection for improved FPD and BW. Data were available for 4 generations from 4 broiler lines, bred with varying intensities of selection for growth. The average BW ranged from 1.7 to 2.4 kg at 5 wk of age. In the pedigree environment, the prevalence of FPD ranged from 14 to 37%, with 3 to 9% being severely affected; in the sib-test environment, these values were correspondingly 45 to 79% and 35 to 70%. Both traits showed re-ranking of the 4 lines in terms of phenotype across the 2 environments, indicating the existence of a genotype-by-environment interaction. In both environments, females showed higher prevalences of FPD than males. In line with their higher prevalence, heritabilities of FPD in the sib-test environment ranged from 0.22 to 0.32, compared with 0.18 to 0.24 for FPD in the pedigree environment (all SE ≤0.02). Estimates of the genetic correlation between FPD in the pedigree and in the sib-test environments were high (0.78–0.82), which suggests that selection against FPD in a highly biosecure environment can improve the genetic merit for birds reared under commercial conditions. Estimates of the genetic associations between FPD and BW were small and varied in sign. Predicted responses to selection showed a yearly reduction in average score of −3.4 to −7.5% for FPD in the pedigree environment and −0.5 to −6.6% for FPD in the sib-test environment, while maintaining improvement of BW of 2.6 to 3.2% and 2.6 to 3.8% of the average BW per year, respectively. This research indicates that balanced genetic selection for both BW and FPD in contrasting environments is an effective strategy to reduce the genetic disposition to develop FPD in broilers.

Influence of dietary enzyme supplementation of barley-based diets on growth performance and footpad dermatitis in broiler chickens exposed to early high-moisture litter

SUMMARY The physicochemical properties of dietary nonstarch polysaccharides in barley and soybean meals have been correlated with increases in excreta viscosity and adherence, and hence footpad dermatitis (FPD), in broiler chickens. Moreover, high litter moisture has been identified as a possible causative agent of FPD. A total of 448 birds were raised in floor pens in a design involving a 2 × 2 × 2 factorial arrangement of barley (0 or 25% of diet), feed enzyme mixture (supplementation with 0 or 0.1% of Farmazyme BR-M), and litter moisture (with or without added water) and a 3-stage feeding program (8 treatments; 32 replicates; 4 replicate pens per treatment combination, with 14 birds per pen). In addition to measuring live performance, the feet were scored on all birds at 14, 28, and 42 d of age, and the severity of FPD lesions was recorded as none, mild, or severe. A subsample of birds was processed at the end of the experiment to evaluate carcass yields. Pooled litter samples were collected for moisture determination (d 5 and 42) and pH (d 42). The incidence and severity of FPD on d 14 and 28 were due only to litter moisture. No effects on litter moisture or pH were due to barley, although growth performance was adversely affected at 25% dietary inclusion. Carcass yields did not differ between treatments (P > 0.05). Performance of birds was significantly improved by supplementing the feed enzyme mixture, irrespective of the addition of barley or the wetting treatment. Hence, management factors play a significant role in the etiology of FPD in broilers.

Number of flocks on the same litter and carcase condemnations due to cellulitis, arthritis and contact foot-pad dermatitis in broilers

1. This study was conducted to verify the impact of different kinds of material and the number of times of litter reuse on the incidence of chicken pathologies. Approximately 4·5 million broilers from conventional Brazilian farms were evaluated in the abattoir for cellulitis, arthritis and contact foot-pad dermatitis. 2. Four different kinds of litter material, Brachiaria grass, corncob, sawdust and rice shell, were used. Brachiaria grass litter showed the highest incidence of contact foot-pad dermatitis. Corncob litter also showed some negative effects on foot quality. Broilers raised on rice shell litter showed good results in terms of the incidence of contact foot-pad dermatitis. The best results were obtained with sawdust litter, because the incidence of cellulitis and arthritis were the lowest and the incidence of contact foot-pad dermatitis was also very low.

Genetic variation of contact dermatitis in broilers

This study aimed to investigate the presence of genetic variation in footpad dermatitis (FPD) and hock burns (HB) and the possibility to genetically select against these. A field trial including 10 commercial broiler lines (n = 102 to 265) was carried out at 2 Dutch farms. Footpad dermatitis and HB were subjectively scored at approximately 4, 5, and 7 wk on a scale from 0 through 5. Genetic parameters were estimated in 2 lines based on a larger data set. The overall agreement of repeated FPD and HB scores was high (0.66 to 0.86) and the scoring system was, therefore, considered reliable. Kendall's tau between left and right scores was lower than 1 (FPD: 0.73 and HB: 0.57), and both left and right FPD and HB must, therefore, be evaluated. High prevalences of FPD, but also HB, were achieved in the field trial, but lower prevalences may be sufficient for genetic evaluations and would be less detrimental to welfare. Genetic variation between and within lines was present for both FPD and HB as indicated by between-line differences and heritabilities, and selection against FPD and HB is, therefore, possible. It is important that selection is done against both FPD and HB, and such selection should not have a negative influence on the genetic improvement in BW. In contrast, continued selection for increased BW while ignoring FPD in the breeding goal is likely to lead to an increased propensity to develop FPD in broilers.

Using a tobit regression model to analyse risk factors for foot-pad dermatitis in commercially grown broilers

A model was developed to explain the influence of different local and regional factors on the prevalence of foot-pad dermatitis in broilers at the time of slaughter. Data from a recent two-year study of broiler foot-health in Sweden were used to construct the model. The model was based on regression analysis, using a Tobit model for censored data. This type of Tobit regression model has been used for several decades in econometrics and can also be found in the medical-scientific literature. It has, however, reportedly not been used in veterinary medicine although there appears to be several situations where it should be considered useful. Week of slaughter was significantly ( p<0.001) associated with total foot-pad score, which decreased over time. The birds' age at slaughter was also significantly ( p<0.01) associated with total foot-pad score. Five out of the 11 slaughterhouses included in the study were included as significant ( p<0.01) variables in the final model. Three feed suppliers ( p<0.05) and four regions ( p<0.01) were also included as significant variables in the model. There were also significant ( p<0.001) interactions between several of these factors (mainly, between the time variable and specific slaughterhouses, feed suppliers or regions, respectively). The information gathered in this study regarding the influence of a number of risk factors for the development of foot-pad dermatitis and their reciprocal interactions will enable us to modify the Swedish broiler foot-health programme.