Effects of type of forage fed to dairy heifers: associations between claw characteristics, clinical lameness, environment and behaviour

Heifers were reared separately on wet fermented (WF) (grass silage based) or dry unfermented (DU) (straw based) diets. Clinical lameness was recorded and physical claw attributes were measured regularly, up to six months after calving at approximately two years of age. Two months before calving, some aspects of animal behaviour and the properties of slurry were studied. The incidence of lameness due to claw horn lesions was significantly higher (P < 0.01) in WF than in DU. WF suffered more serious heel erosion prior to calving (P < 0.05) and had softer claw horn at two (heel and axial sole) out of five sites throughout (P < 0.01 and P < 0.05). The slurry produced by WF had lower total solids content (P < 0.05) and viscosity (P < 0.001). WF spent longer standing and feeding (P < 0.001). It is proposed that standing for longer in less viscous slurry contributed to softer claw horn and more severe heel erosion, predisposing WF to claw horn lesions causing lameness. Reducing contact with low dry matter slurry is recommended for improving claw health.     

Effect of lameness on milk yield in dairy cows

OBJECTIVE: To examine the relationship between lameness and milk yield in dairy cows. DESIGN: Cohort study. ANIMALS: 531 dairy cows. PROCEDURE: Cows affected with lameness were classified into 1 of 3 groups on the basis of type of diseases or lesions observed, including interdigital phlegmon (foot rot), papillomatous digital dermatitis (foot warts), or claw lesions. Cows not affected with lameness were classified as healthy. From Dairy Herd Improvement Association records, 305-day mature equivalent milk yield data were collected at the end of lactation or when the cow left the herd. Milk yield was compared between cows affected with lameness and healthy cows. RESULTS: 167 (31%) cows were affected with lameness during lactation. Lame cows had claw lesions (60%), papillomatous digital dermatitis (31%), or interdigital phlegmon (9%). Milk yield in lame cows with interdigital phlegmon (mean, 17,122 lb) was significantly less, compared with healthy cows (19,007 lb). CONCLUSIONS AND CLINICAL RELEVANCE: In this herd, interdigital phlegmon was associated with a 10% decrease in milk production. Lame cows with claw lesions or papillomatous digital dermatitis produced less milk than healthy cows, but the difference was not significant.     

Relationship between herd-level incidence rate of energy-related postpartum diseases,general risk factors and claw lesions in individual dairy cows recorded at maintenance claw trimming

Background

Laminitis and energy-related postpartum diseases share several risk factors, indicating a common etiology. Thus, a herd’s incidence rate of energy-related postpartum diseases, such as displaced abomasum and clinical ketosis, might reflect the likelihood of cows to suffer from laminitis-related claw lesions. The aim of this study was to investigate the association between herd-level incidence rate of displaced abomasum and clinical ketosis, general risk factors, and claw lesions in individual cows recorded at maintenance claw trimming.

Methods

The dataset consisted of 6773 trimmings, performed between 2004 and 2006 by professional trimmers, from 3607 Swedish Red and Swedish Holstein cows in 26 herds. The herds were classified as having a high, inconsistent-high or low incidence rate of energy-related postpartum diseases, based on the number of recorded cases of veterinary-diagnosed displaced abomasum and clinical ketosis in the Swedish national animal disease recording system during 2002 to 2006, and observations and interviews in connections with herd visits. Generalized linear mixed models were used to investigate the association between herd-level incidence rate of energy-related postpartum diseases and laminitis-related lesions including sole ulcer and sole hemorrhage; and hygiene-related lesions including interdigital dermatitis, digital dermatitis, heel-horn erosion, verrucose dermatitis, and interdigital hyperplasia; and absence of any claw lesion. Systematic effects, including first-order interactions, with P < 0.05 were included in the models. Herd classification was forced into the models, and a random effect of herd was included.

Results

In comparison to herds with a high incidence rate of energy-related postpartum diseases, low-incidence herds showed a lower odds ratio (OR; 0.2) for laminitis-related lesions in cows trimmed during the summer months. Low-incidence herds also showed numerically lower OR estimates for laminitis-related lesions in all parity classes and a numerically lower OR for hygiene-related lesions. In addition, low-incidence herds showed tendencies towards a numerically higher OR for absence of any lesion, irrespective of trimming season or parity.

Conclusions

Only a few statistically significant associations were found, but several tendencies pointed towards better claw health in herds with low as compared with high incidence rate of energy-related postpartum diseases.     

Prevalence of foot lesions in Danish Holstein cows

In a cross-sectional study of 6240 Danish Holstein cows in 55 herds using loose-housing systems, sole haemorrhages and heel horn erosions occurred frequently in almost all the herds. Digital dermatitis occurred in 47 of the 55 herds (85 per cent). Spearman correlation coefficients revealed relationships between lameness and sole ulcer (0.36), between heel horn erosion and sole haemorrhage (0.39), between heel horn erosion and interdigital dermatitis (0.29) and between sole ulcer and double sole (0.26). The prevalence of heel horn erosion, sole haemorrhage, interdigital dermatitis and digital dermatitis appeared to be most affected by herd-level factors. The associations between individual foot trimmers and all the foot lesions were statistically significant. The risk of interdigital dermatitis increased with decreasing amounts of bedding. Cows housed throughout the year had a marginally higher risk of sole haemorrhage.     

Treatment of Malassezia pachydermatis-associated seborrhoeic dermatitis in Devon Rex cats with itraconazole--a pilot study

Treatment of Malassezia pachydermatis-associated seborrhoeic dermatitis with oral itraconazole was investigated in six Devon Rex cats (DRC). The cutaneous populations of Malassezia were determined using contact plates and a swab-wash method before and after 21 days of pulse treatment with itraconazole (5 mg kg-1 once daily, 7 days on, 7 days off, 7 days on). Before treatment, all cats had greasy seborrhoeic dermatitis involving the axillae, groin, claw folds and palmar and plantar interdigital skin, and two had similar lesions on the ventral neck. After treatment, there was a significant (P<0.05) reduction in overall clinical scores and in scores at all individual sites assessed, except for the interdigital skin (P=0.068). Population sizes of M. pachydermatis in the left and right axillae, left and right groin and palmar interdigital skin were significantly (P<0.05) reduced, whereas the reduction in claw fold counts did not reach significance (P=0.068). The dramatic reduction in yeast counts and an associated marked clinical improvement of the seborrhoeic dermatitis provide important pilot data on the potential value of oral itraconazole in the management of seborrhoeic dermatitis associated with M. pachydermatis in DRC.     

Prevalence of claw lesions in Norwegian dairy cattle housed in tie stalls and free stalls

Approximately 88% of Norwegian dairy cattle are housed in tie stalls. Free-stall housing will be implemented for all cattle within 20 years. This means that most existing barns have to be rebuilt in the near future. We designed our study to estimate the prevalence of claw lesions in Norway and to reveal possible differences between tie stalls and free stalls. Fifty-five tie-stall herds and 57 free-stall herds were sampled by computerized systematic selection and 2665 cows were trimmed by 13 claw trimmers, during the late winter and spring of 2002. The claw trimmers had been taught diagnosing and recording of claw lesions. Environmental factors, management and feeding routines also were recorded. Forty-eight percent of cows housed in tie stalls had one or more claw lesions versus 71.8% in free stalls. Prevalences recorded in the hind claws were: 4.2% of the animals had dermatitis in tie stalls versus 5.7% in free stalls; 7.9% versus 38.0% had heel–horn erosions; 7.3% versus 13.6% had haemorrhages of the white line; 11.7% versus 20.4% had haemorrhages of the sole; 2.8% versus 3.2% had sole ulcers and 5.5% versus 9.7% had white-line fissures. Most lesions were mild. A model was designed to estimate cluster effects within herd and within claw trimmer. The cluster effect within herd was significant for all lesions. The cluster effect within claw trimmer was only significant for heel–horn erosions in front and hind claws and for white-line fissures in front claws. Agreements between some of the claw lesions were revealed. The study confirms that in Norwegian dairy cattle, most claw lesions are more prevalent in free stalls than in tie stalls.     

Supplementary biotin for sows: effect on claw integrity

Eighty female pigs were fed, from 25 kg liveweight, either basal diets calculated to provide 32 micrograms available biotin/kg (control diet) or basal diets supplemented with 350 micrograms biotin/kg. Their claws were examined and lesions recorded at 170 days of age and when each of their first four litters was weaned. The incidence of horn 'defects' (superficial bruises, abrasions and cuts in the soft heel) remained at a low level throughout the trial. Neither the number of claws affected with lesions nor the number of lesions per sow differed between treatments at 170 days of age. Between 170 days of age and first weaning the incidence of hoof lesions increased greatly. At first weaning and for the remainder of the trial biotin supplemented sows had significantly fewer claw lesions per sow than controls (P less than 0.05 or greater). The predominant injuries to the foot were cracks which occurred mainly in two associated regions, the heel/toe junction and the heel, and the sidewall and adjacent white-line region of the toe. The differences in foot damage did not result in differences in culling rate. It was concluded that supplemention of the diet of breeding sows with biotin from an early stage of development made a significant contribution to the maintenance of their horn integrity.     

A longitudinal study of the hooves of non-lame cows

A longitudinal study of the feet of cows from a seasonal dairy herd was conducted over a 12 month period to measure the occurrence of subclinical hoof lesions. Eleven 2-year-old cows, entering the herd for the first time, and eleven mature cows were randomly selected from a herd of 415 cows at the end of winter (July 1989) prior to calving. The incidence of lameness in the herd over the 12 months was 2%. None of the trial cows became lame during the study. Cows were examined monthly. The type, severity and location of any hoof lesions were recorded. Sole haemorrhage, erosion of the heel bulb and minor white line separation were the most commonly observed lesions. These lesions were observed with specific claw distributions in the cow and at specific times of the year and breeding season, with waves of each type of lesion passing through the herd at a particular time. White line separation was observed commonly during spring (up to 37% of digits affected), disappeared almost completely over the dry summer months and reappeared in autumn, increasing to 40%' again over winter. Lesions were more commonly observed in the lateral digits, with fore feet being more commonly affected than hind feet. Erosion of the heel bulbs was common in August (65% of digits affected, more common in mature cows than 2-year-olds), disappeared quickly during spring, and reappeared in all cows during the following winter (88% of digits; no age differences). There were no differences in distribution between digits. Sole haemorrhages were concentrated over the mid-sole and abaxial sole zones. They were more common in the hind feet than the front feet and more common in the outside claws (p < 0.001). Haemorrhages were not observed prior to or soon after calving, appeared in October and reached a peak of 40% in December, then gradually disappeared by the time of drying-off in May. The 2-year-olds were more frequently affected than the mature cows (p <0.001).     

Healing process of claw lesions in dairy cows in alpine mountain pastures

The field study investigated severity, localisation and incidence of claw lesions of dairy cows and their healing process during a period of three months on selected mountain pastures in the central part of Switzerland. In 60 cows, which were at least 120 days in their lactation, the healing process was compared with the biochemical profiles. In 141 cows 197 claw lesions were recorded. Diagnosed were only sole ulcers (38%) and white line lesions (62%). In the first and second half of the summer term, the number of claw lesions was equal, although more severe lesions occurred mainly during the second half (89%). The lesions were treated surgically and the affected claw was elevated on a wood block or a plastic shoe. Average time for formation of a close layer of horn was 14 days. A delayed healing process was observed in dairy cows with an milk yield over 5500 kg per lactation, as well as in the second half of the summer term. Cows with a delayed healing process had significantly higher concentrations of free fatty acids and beta-hydroxybutyrate, and higher plasma enzyme activities for AST than cows with adequate healing process. This indicates that cows with a relatively high milk production touch upon the limits of their physical capacity under harder conditions on alpine pastures, which may affect also the healing process of claw lesions.     

Lesions causing lameness requiring veterinary treatment in pasture-fed dairy cows in East Gippsland

In 653 mature dairy cows examined for lameness between February 1987 and July 1988 there were 783 lesions identified. Most of these were located below the pastern (90.5%) and most lesions involved hindlimbs (79%). Of digital and interdigital lesions, hind limbs had the most lesions (69.2%). Medial digits of forelimbs were least affected (7.8%) and lateral digits of hindlimbs were the most affected (44.4%). Lateral digits of forelimbs were slightly more affected than medial digits of hindlimbs (17.0% vs 14.8%). Ten different types of lesions contributed to 84.5% of foot lameness. Most common were axial wall cracks (21.7%), underrun sole (14.6%), footrot (13.0%), punctured sole (9.3%) and white line disease (7.2%). Age, rainfall and the early lactation period were factors determining the incidence of lameness.     

The effect of an acidified, ionized copper sulphate solution on digital dermatitis in dairy cows

Digital dermatitis (DD) is the most important infectious claw disorder in dairy cattle and herd-based foot bathing with antibacterials, such as 4% formalin, is often used to prevent it. However, there is a lack of long-term studies of the effectiveness of such regimes and in this study the preventive and curative effect of 4% formalin was compared with that of an acidified, ionized copper sulphate solution over a 4-month period on a commercial 120-cow dairy farm. The cows were walked through a split-leg footbath where left claws were treated with an acidified copper solution twice daily for 5days/week, while right claws were treated with 4% formalin twice daily for 1day/every second week. Hind claws were scored for the presence and severity of DD in a trimming chute at the start of the study and every 4weeks throughout the study period. At the start of the study 21/110 cows had ulcerative DD lesions with 10 on the left hind foot, 8 on the right and 3 on both. These lesions, as well as any new lesions which arose during the study, were treated with chlortetracycline spray. During the study 440 observations were made and seven new DD lesions were recorded on left feet (copper treated) and 20 on right feet (formalin treated). Based on survival analysis, the risk of developing a new ulcerative DD lesion on copper-treated (left hind) feet was almost three times less (RR=0.37, 95% CI 0.16-0.91) than formalin-treated (right hind) feet. Cure rates of DD lesions were not different between copper and formalin.     

Comparison of phytohemagglutinin-induced cutaneous hypersensitivity reactions in the interdigital skin of broiler and layer chicks

Cutaneous basophil hypersensitivity (CBH) responses elicited by intradermal injection of phytohemagglutinin-P (PHA-P) were evaluated in the interdigital skin of broiler and layer chicks. Five- and 10-day-old broiler and layer chicks were injected intradermally in the interdigital skin between the third and fourth digits of the right foot with 25, 50, or 100 micrograms of PHA-P. The PHA-P-elicited CBH responses were evaluated by determining interdigital skin thickness before injection and 12 and 24 hr after injection. The effect of treatment with the T-lymphocyte-suppressing drug cyclosporin on the CBH responses was determined in chicks treated daily for 4 days before skin-testing at 10 days of age. Injection of PHA-P caused significant increases (P less than 0.005) in skin thickness at all dose amounts, with the maximum CBH response elicited by 100 micrograms PHA-P. The CBH response was significantly higher (P less than 0.05) in broilers than in layers. Treatment with cyclosporin significantly suppressed (P less than 0.01) the CBH response in 10-day-old chicks of both types. Results indicate that the interdigital skin-test is a rapid, simple means of assessing normal and suppressed T-lymphocyte-mediated immune response in broiler and layer chicks.     

A longitudinal study into the effect of grazing on claw disorders in female calves and young dairy cows

To estimate the prevalence of claw disorders in youngstock and first parity heifers and to evaluate the effect of grazing on claw disorders, 10 Dutch dairy herds participated in a 2-year longitudinal study. Five herds were zero-grazed, while in the other five herds cows and youngstock had access to pasture during the summer. Twenty female calves <1year of age and 20 females between 1 and 2years of age were randomly selected on each farm, and were individually monitored at 3 monthly intervals for 2years. Data from 366 animals with at least five observations were analysed using linear mixed models with a binomial error distribution. Independent variables were grazing, age, month of observation and previous occurrence of the disorder, while herd and animal were included as random effects. Of these 366 animals, 287 had calved once and 76 twice at the end of the study. Analytic results were obtained for digital dermatitis (DD), interdigital dermatitis/heel horn erosion (IDHE) and sole haemorrhages (SH), all of which had a prevalence of >15%. The prevalence of DD increased considerably around first calving on both the grazing and the zero-grazing farms. The prevalence of IDHE increased with age while SH prevalence showed a more fluctuating pattern. Digital dermatitis was less frequently observed in pastured animals than in permanently housed animals (OR=0.12-0.64 depending on month of observation; P<0.05), with the strongest effect being seen during the period when the herds which grazed cattle actually had animals at pasture (May to August). Grazing was also associated with lower levels of IDHE and SH, again particularly during the grazing season.     

Swelling of cattle heel horn by urine

OBJECTIVES: To understand the likely mechanisms responsible for heel horn softening when cattle stand in their own effluent. To examine the effectiveness of some footbath chemicals in preventing heel horn softening. PROCEDURE: Shavings from the heels of cattle were used in a laboratory test to examine the swelling effects of cow urine, urea, sulphide and ammonia. Formalin, glutaraldehyde, glyoxal, zinc sulphate, copper sulphate, alum, tannic acid and a compound containing nitrocellulose plus nylon, were compared for their ability to prevent swelling in heel shavings induced by urea plus 2-mercaptoethanol. RESULTS: Cow urine caused heel horn to swell. Urea caused swelling at concentrations normally found in cow urine. Sulphide caused swelling at concentrations normally found in cow slurry. Low concentrations of ammonia solution also resulted in swelling. Formalin and glutaraldehyde prevented swelling induced by high concentrations of urea plus 2-mercaptoethanol. Copper sulphate had a moderate anti-swelling effect. Zinc sulphate, alum, tannic acid, and nitrocellulose plus nylon were relatively ineffective in preventing swelling. CONCLUSIONS: Cow urine can cause degradation of heel horn in cattle feet. The chemical agents that cause this could be urea, sulphide anions and ammonia. Degradation by urine can be prevented by pretreating heel horn with formalin. Glutaraldehyde may be an effective noncarcinogenic alternative to formalin.     

Clinical course of digital dermatitis lesions in an endemically infected herd without preventive herd strategies

Lactating Holstein-Friesian dairy cows in four separately housed groups in a herd with endemic digital dermatitis (DD) were monitored weekly for 4 weeks in December 2004 for the presence of and transition between five stages (M0-M4) of DD. Cows were also monitored for the presence of heel horn erosion (HHE) and interdigital hyperplasia. Prior to the study, two groups had been housed indoors on a high or low energy ration, one group had been grazed and one was a dry cow group. All cows received the same ration during the period of investigation. 'Active infection' was defined as transition from M0, M1, M3 or M4 to M2 and 'resolving M2 lesions' were defined as transition from M2 to another stage. M2 lesions were diagnosed on 106 occasions in the hind claws of 49 (36%) of 138 dairy cows; both hind claws were affected in nine cases (18%). M2 lesions were more often painful on palpation than other stages; 94% of M2 lesions were located plantar-medially near the interdigital cleft and 71% had a diameter of 2-4 cm. More M1 lesions than other stages were found within the interdigital space. When interdigital hyperplasia was present, claws were always concurrently affected by DD. The baseline incidence for 'active infection' was 6% per week, increasing to 11% when HHE was present, 14% when cows were previously housed indoors and fed a high energy ration and 16% when cows were 60-120 days in lactation. Topical treatment with chlortetracycline resulted in resolution from M2 of 79% per week. There were no significant effects of group, stage of lactation, parity or HHE on resolution of M2 lesions.     

The development of skin,claw and teat lesions in sows and piglets in farrowing crates with two concrete flooring materials

Abstract

The aim of the study was to investigate lesions in sows and their piglets kept on two flooring materials – bare concrete and concrete coated with polyurethane containing sand. In total, 13 lactations on concrete and 11 on polyurethane were evaluated. The severity of skin lesions was scored and teat and claw lesions were recorded. The sand-filled coating was rougher compared to the concrete floor. Larger litter sizes were associated with a higher proportion of wounded teats in sows. Only seven of the 230 piglets had no skin lesions. The piglet skin lesions generally healed, since the number of more severe lesions decreased (p<0.001) and the number of less severe lesions (p<0.001) increased over time. Piglet lesions were associated with daily weight gain and litter size. The number of skin lesions on sows and piglets did not differ between animals kept on concrete and polyurethane-covered flooring. However, piglets kept on the latter flooring had more frequent claw lesions. On both types of flooring the majority of the piglets had skin lesions. Piglets had more claw lesions on polyurethane coating due to its roughness. In addition to the possibility of lower weight gains in piglets due to severe lesions, pig skin lesions are themselves a severe welfare problem in this type of housing system.     

Evaluation of claw health in heifers in seven dairy farms using a digital claw trimming protocol and claw data analysis system

The claw health of 139 heifers with a mean age of 22.1 months (SD: 2.6) in seven free stall dairy farms in Lower Austria was evaluated. Claw lesions were assessed during functional claw trimming and documented and analysed using the digital program Claw Manager. For documentation of lesions, each claw was divided into ten zones. The prevalence of lameness, claw lesions and their severity were determined, furthermore the Cow-Claw-Scores (CCS), Farm-Claw-Scores (FCS) and Farm-Zone-Scores (FZS) were calculated.The FCS between farms was tested for significant differences. A lameness prevalence of 9.4% and an overall prevalence of claw lesions of 98.5% were recorded in these 139 heifers.The most commonly diagnosed disorders were white line lesions (WLL) with a prevalence of 87.1%, heel horn erosion (84.9%), double soles (DS; 47.5%), sole haemorrhages (SH; 33.1%) and a concave dorsal wall contour in 15.1% of the heifers. High correlation coefficients (r > or = 0.93) were found between SH and DS, WLL and DS. 86.5% of all diagnosed claw lesions were score 1 (mild), 11.1% score 2 (moderate) and 2.4% score 3 (severe) lesions. The CCS in all heifers ranged between 0 and 267, and the FCS in the seven herds was between eleven and 55. Claw zone 3 was affected most frequently and severely. Following the results of this study, systematic functional claw trimming and consequent documentation of detected claw lesions is highly recommended for heifers at the time of their first insemination to prevent claw disorders in lactating cows and to improve their well-being.     

"Subclinical" laminitis in dairy cattle

In dairying countries worldwide, the economic importance of lameness in cattle is now recognised. Laminitis is regarded as a major predisposing factor in lameness caused by claw disorders such as white zone lesions, sole ulcer, and heel horn erosion. The existence of subclinical laminitis was first suggested in the late 1970s by Dutch workers describing the symptoms of sole haemorrhages and yellowish-coloured, soft sole horn. In an attempt to clarify some of the confusing and often conflicting terminology, the literature on laminitis is reviewed. Disturbed haemodynamics, in particular repeated or prolonged dilation of arteriovenous anastomoses, have been implicated in the pathogenesis of both equine and bovine laminitis. Some characteristics of the vascular system of the bovine claw which may be of importance in the pathophysiology of the subclinical laminitis syndrome are therefore discussed. Clinical observations suggest that subclinical laminitis is a multifactorial disease. The different factors that are or may be involved in its aetiology vary in complexity and severity according to the management protocol of the animals. The possible involvement of subclinical laminitis in claw lesions is assessed.     

Quantities and types of ceramides and their relationships to physical properties of the horn covering the claws of clinically normal cows and cows with subclinical laminitis

Quantities and types of ceramides and their relationships to physical properties of the horn covering the claws of clinically normal cows and cows with subclinical laminitis were investigated. Total ceramide content of the horn covering the sole and wall from cows with subclinical laminitis was 872.2 +/- 146.6 microg/g and 528.6 +/- 61.3 microg/g, respectively, and was significantly (P < 0.01, 0.05) lower than that from clinically normal cows. The mean moisture content in the claws from cows with subclinical laminitis (43.5% +/- 4.3%) was significantly (P < 0.05) higher than that in the claws from clinically normal cows. The hardness of claws from cows with subclinical laminitis (35.2 +/- 3.5) was significantly (P < 0.05) less than that of claws from clinically normal cows. Significant correlations between ceramides and moisture content (P < 0.001) and between ceramide and hardness (P < 0.001) were found in clinically normal cows and cows with subclinical laminitis. Our results indicate that decreases in ceramide contents may be related to changes in physical properties of the horn covering the claw in cows with subclinical laminitis.     

Supplemental biotin for swine. III. Influence of supplementation to corn- and wheat-based diets on the incidence and severity of toe lesions, hair and skin characteristics and structural soundness of sows housed in confinement during four parities

The influence of supplementing 0 (NB) or 440 (SB) micrograms biotin/kg to corn- or wheat-based diets on toe lesions, hair characteristics and structural soundness in 116 crossbred female swine was studied from selection (100 kg) until completion of four parities. Gilts that had been previously fed corn-soybean meal diets with 0 or 220 micrograms supplemental biotin/kg diet during growth and development, remained on either the biotin unsupplemented or supplemented diet. Females were housed in buildings containing partially slatted and solid concrete floors. Toe, hair and soundness evaluations were made at a mean age of 240, 521, 732, 916 and 1,090 d. Type of grain fed did not influence (P greater than .10) any response criteria evaluated. Six types of toe lesions were observed across all dietary treatments and varied in severity from minor to very severe. The percentage of females with heel cracks, heel-horn junction cracks and side-wall horn cracks was reduced (P less than .01) when females were fed SB diets. Females fed SB diets had fewer (P less than .001) total lesions, heel cracks, heel-horn junction cracks, side-wall horn cracks and white-line horn cracks (P less than .03) compared with females consuming NB diets. In general, biotin supplementation was more effective in reducing the number and percentage of toe lesions in multiparous sows compared with gilts and primiparous sows. Biotin supplementation increased (P less than .001) the number of hairs/cm2 skin and improved (P less than .001) hair scores. Histological evaluation and soundness scores were not affected (P greater than .10) by level of biotin fed.(ABSTRACT TRUNCATED AT 250 WORDS)