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2 Summary TOE ULCER: THE MOST IMPORTANT DISEASE IN FIRST - CALVING HOLSTEIN COWS UNDER GRAZING CONDITIONS R. Acuña DMV, R. Scarsi DMV, MS, Ph.D. Data are reported on foot diseases in dairy cattle. They were obtained from three dairy farms in Uruguay which operated under grazing conditions. Dairy farm 1. There were 850 milking cows including 140 first-calving cows. From these, 59 (42%) showed lameness. After being examined, 37(25%) showed Toe Ulcers in their rear legs, mostly affecting the external digit (70%). The remaining lame cows had Interdigital Dermatitis(ID) and Distal Interphalangeal Arthritis(DIA). The cows walked approximately 7 kilometers a day, on a road full of mud and manure. Dairy farm 2. Two hundred and eighty milking cows. There were 43 first calving cows that presented lameness, and 27 of them were affected by Toe Ulcers. Other lesions were; ID, DIA and Coronary Phlegmons. Sole ulcers were not observed at their typical locations. These cows walked 6-8 kilometers daily. Dairy farm 3. This farm had 520 milking cows. One of us (R.A) was called for assistance because there was a problem of lameness affecting 63 first calving cows. At the time the veterinarian was called to visit the farm, 20 first-calving cows had already died. Necropsy findings in two of the animals showed extensive phlegmons affecting the back of the leg beginning at the pastern area. The cause of death was septicemia. The remaining 43 affected cows were clinically examined. Toe Ulcers were found in 32(60%) of them, and the third phalanx was extremely detached in 8 cases suggesting fracture or osteitis. Additional lesions found were White Line Disease(WLD), Foot Rot, and interdigital-dermatitis (ID). Cows at this farm walked 6 kilometers daily on roads covered by manure and mud. Preventive trimming was not done at any of the dairy farms. The lame animals sole thickness were less than 3 millimeters. Overgrowth was not observed in any of the cases. It is concluded that the Toe Ulcer is the most serious disease observed in first-calving dairy cows under grazing conditions. Introduction There are relatively few reports of sole lesions occurring in zone 1 (Greenough and Vermunt). In a bibliographical review of the topic, some publications referred to toe ulcers and toe abscesses but we believe that this last classification does not fit the lesions observed according to the definition of an abscess. This term does not seem to be the appropriate in relation to lesions occuring in the apex (Kofler). The aetiopathogenesis of the toe ulcer seems to be related to three main factors: 1) excessive wear of the sole, 2) separation of the axial or abaxial part of the white line in the apex and, 3) downward rotation and advancement of the third phalanx, pinching the solar corium in its anterior part (Van Amstel). However, osteitis of the third phalanx should be also be considered even if there is no apparent or obvious defect in the sole ( Greenough and Bergsten). Under grazing conditions in which animals are managed by milk producers in South America, where the feeding practices include pasture and supplementation of concentrate feed and corn silage, we have observed that toe ulcers represents the most common lesions in heifers 15 to 276

3 60 days post calving. Two types of toe ulcer lesions are usually presented. One is a single claw horn defect occurring in zone 1 which after further examination, granulation tissue is often observed. This lesion generally responds well to local treatment with hydrogen peroxide and the application of an orthopedic block on the healthy claw. The second type of lesion is more severe and includes bone problems with osteolisis and bone sequestrum, complicated by the anaerobic conditions that are ideal for putrefactive bacteria (Brizzi). The initial lesions appear within 15 days post-calving, with complications in many cases by day thirty. We observed signs of subclinical laminitis which we believe was serving to complicate the original problem. The animals in the initial stage of the disease exhibited a slower gait and were reluctant to move. After a few days animals exhibited severe lameness in affected legs with swelling at the coronary band. The lateral claws of hind feet were most commonly affected (70%), but medial hind claws and front feet also had lesions. Materials and Methods Three dairy farms with seasonal parturition in the fall (March-April) were studied, with a total of 320 heifers giving birth, of which 165 suffered lameness after 15 to 60 days post calving. Table 1 displays the incidence of the problem. It should be noted that these observations were made during a period of months in which 300 mm of rain fell with an average of 80% humidity. In all the cases the animals walked five kms. daily on roads with plenty of mud and manure. In farms 1 and 3 the heifers were milked separately from the cows. Cows and heifers were milked together in farm 2. In all three operations, acclimatization of the heifers was carried out before calving (on the average twenty days before parturition), with feed and supplements similar to those they would receive after giving birth (corn silage and bran wheat). Table 1. Occurrence of lameness and toe ulcers in heifers from 3 dairy farms in Uruguay. FARM HEIFERS LAMENESS TOE ULCER ( 63 % ) ( 62,7% ) (-20 ) 32 ( 50,7% ) TOTAL ( 58,2 %) Preventive hoof trimming was not performed at any of these dairy operations. A conventional Wopa chute was used to restrain cows for examination and trimming (The Netherlands). The animals were selected for examination according to their symptoms, using the scoring system proposed by Bulgarelli and Van Amerongen. Acepromazine was used to sedate the animals. 277

4 Results Group 1 heifers (at 20 days postpartum) had lesions such as those observed in Pictures 1-a and 1-b, whereas animals in Group 2 (more than 20 days postpartum) exhibited lesions like those displayed in Picture 2. What caught the attention of the authors, was the extreme thinness of the sole (less than 3 mm) exhibited in picture 3. Picture 1-a Picture 1-b Picture 2 For the treatment of animals in group one, orthopedic blocks (Demotec 85 or Easy Block) were applied. In addition, it was suggested that the animals be rested in a clean dry place for a period of five days. Those in group two were also treated by the application of an orthopedic block and corrective trimming to remove all necrotic tissue. Cotton wrapped in gauze and soaked in hydrogen peroxide were placed on the lesions followed by closure of the lesion with Demotec glue resin. Picture 3 In those animals which presented with lesions in both digits, Easy Blocks with the toe portion removed were used, but the results were not good. Since it was important that these animals be kept dry and the weather was wet, at a future examination we observed that thirty percent of treated animals presented with hyperextension of the deep flexor tendon in their external digit. Another 30% were sent to slaughter and the remaining 40% presented different alterations with sole ulcers appearing in typical areas. Conclusions Toe ulcers are the most important lesion in calving heifers under pasture grazing conditions like those practiced in Uruguay, where abrupt nutritional changes are common immediately after calving in autumn with high humidity and rainfall. The initial lesions have a good prognosis if they are treated in time, but lesions with bone compromise have a very poor prognosis. However, according to the analysis of risk factors it is the subclinical laminitis that 278

5 increases the graveness of the condition. The early treatment of the initial lesions proved to be effective, but when lesions involved the bone of the third phalanx, treatment was more difficult and had a poor prognosis. Acknowledgements Nichelle Martin (Writing expressions) for her kind cooperation. Leslie Shearer for her adviser. References 1. Brizzi A communication. 2. Bulgarelli; Van Amerongen, et al. A hind foot position scoring system to monitor sub clinical lameness in Dutch Holstein Friesian cows. Dept of herd health & Reproduction, Utrecht University, The Netherlands. 3. Greenough P.R., et al Laminitis-like changes in the claw of feedlot cattle. Canadian Vet J 31: Greenough P.R communication. 5. Kofler J Clinical study of toe ulcer and necrosis of the apex of the distal phalanx in 53 cattle. Vet J 157(2): Miskimins D.W Bovine toe abscesses. Eighth Symposium on Disorders of the Ruminant Digit. Banff, Canada, pp Van Amstel S.R Toe abscess: A serious cause of lameness in the U.S. Dairy Industry. XI. Symposium on Disorders of the Ruminant Digit. Parma, Italy; pp

6 YIELDING WALKING AREAS IN LOOSE HOUSE SYSTEMS B. Benz, 1 H. Wandel, T. Jungbluth Institute of Agricultural Engineering, University of Hohenheim (440), Stuttgart, Germany Introduction Lameness, the complex economic and welfare problem in dairy cattle, is directly linked to the flooring in loose house systems (STEFANOWSKA, 1998). Cattle originated on the grass pastures and hill terrain of Europe, where grass pastures and dirt lots provided them with walking surfaces that yielded under the pressure of the hoof (BURGI, 1998). In Germany at present, about 20 % of all cows have to be treated at least once a year due to lameness (ZEDDIES, 1997). Mobility is the most important prerequisite for the smooth functioning of a loose house system. Most disorders are concentrated on the hind legs and, especially, on the outer claw. A closer look at the anatomy of a cow shows, that the hind legs, although suitable for their primary function in forward propulsion, have little ability for shock-absorbance, because they are connected by joints. In contrast, the front legs, that have to catch the propulsive energy, are better designed for this purpose, as they possess an elastic connection to the shoulder blade. The following study aims at creating a farming systems that can, in part, model the original softer footing (grass pastures) environment of a cow without any significant indication of claw disease. Material and Method The test is being carried out on two farms, each with 60 dairy cows. Both loose house systems offer comfortable cubicles to avoid prolonged standing. Animal behaviour and claw diagnosis have been recorded, with biological and ethological parameters, in three steps. Firstly, on concrete slatted floors, secondly, on slatted floors covered with rubber mats, and thirdly, again on concrete slatted floors. Slip resistance tests were carried out and confirm the knowledge, that generally, slatted floors older than 5 years have to be seen as being too slippery for cows to walk on. As an appropriate surface material, only compact rubber mats came in question, because they can be cut to fit the slatted floors, and hence do not impede the self-cleaningfunction. The elasticity of rubber mats is mainly dependent on the thickness and structure of the bottom side. The top side of the 3 cm thick KSL mats (Gummiwerk Kraiburg, Germany) is covered by a hammer scale profile and the bottom side by conical burls of differing height (see figures 1, 2 and 3). Claw diagnosis, based on region, description and severity, are recorded every three month during claw trimming. Differences in claw sizes are measured to control horn growth. Cow behaviour is observed and floor characterizing parameters, like walking speed, step length, amount of steps per hour, slipping and caudal licking are recorded. Results and Discussion Claw diagnosis, divided up into 5 severities ranging from 1 (very slight) to 5 (very severe), is the most important parameter for the comparison between hard and yielding floors. Lesions on the wall are inflicted when cows walk and slip on slatted floors leading to an overloading 1 Contact at: Tel: l; Fax: ; Benz-Loeffingen@t-online.de 280

7 of the sole. This can be considered as a predisposing factor for mechanically caused claw diseases, such as laminitis, sole bruises, or even sole ulcers. After installing the yielding rubber mats however, lesions of the wall moved statistically significant from severe to slightly severe. Laminitis is accepted as main risk factor for all the other claw diseases. Although laminitis is a multifactorial problem, it is obvious that yielding floors achieve at least a decrease in sole bleedings. In the white line region, bleedings show an injury of the suspensory apparatus. The pedal bone sinks in the hornshoe and the quick is bruised between sole and bone. Yielding floors moderate the consequences of laminitis, shown clearly by the sinking amount and slightly severity of sole bruises and sole ulcers. After installing the yielding rubber mats, a peeling of the thin layers of the sole horn was observed, which is part of the natural horn growth regulation (see figure 4). This is a positive mechanism, as it indicates that the weight-bearing boarder is assuming the main weight and the sole is carrying only additional weight as the claw sinks on the yielding surface. Consequently, there is no overloading of the sole or typical bruising. In intense dairy cattle husbandry, in contrast to the primordial situation, regularly claw trimming is necessary. Unbalanced weight distribution and local overloading have to be corrected when the horn growth rate exceeds horn abrasion, and natural horn growth regulation is missing. Generally, a moderate horn growth is desired. However, immoderate horn growth is dependent on many factors such as the reaction of heel horn erosion, laminitis, hypertrophy and abrasion. No difference in horn growth was detected between yielding and hard slatted floors. The floors do not only influence claw health but especially animal behaviour. In particular, caudal licking is a valuable characteristic behaviour to observe when determining the quality of the floors, as the animals are in an instable position with one hind leg lifted and the diagonal positioned front leg in danger of slipping. More frequent caudal licking was observed on yielding floors, where the animals licked themselves more than twice and never slipped. When the rubber mats were removed, the animals adapted immediately to the slippery floor (see figure 5). Obviously, the animals renounce their previous behaviour in response to the slipping danger. Not only is the amount of comfort behaviour (caudal licking) observed of importance, but decisive for the hygiene, is also the manner of the movement. Fearing to slip, the animals have little or no confidence in licking. Yet caudal licking might be important for the hygiene between the udder and leg. Step length on yielding floors (about 80 cm) is comparative to pasture and differs evidently to step length on concrete floors (less than 60 cm). Also walking speed increases on yielding slatted floors and statistically significant (81 steps/h (hard floor) and 99 steps/h (yielding floor)) more steps were counted. Conclusions The experiment shows that soft floors favour the requirements for the correct functioning of the claw and unimpeded cow behaviour. Further studies aim to prove that horn quality is strongly dependent on unimpeded locomotion because it is probable that a close relationship exists between the biomechanics, the microcirculation and the nutrition of the living cells that nourish the horn producing tissues of the claw. The advantage of installing the rubber mats is that this one precaution solves two walking area problems in one, namely insuffient slip resistence and floor hardness. Preventing lameness means considerably reducing milk and fertility losses and, as the experiments have shown, investing in a cow s comfort is definitely profitable in the long term. Not only do economical aspects favour the installation of yielding rubber mats, but also ethical issues are of great importance today, especially amongst 281

8 consumers. Cows mirror their needs quite clearly through their behaviour and this, together with a deeper understanding of their anatomy and physiology, can lead to farming methods that lend themselves better to the original habitat of dairy cows namely, grass pastures. References 1. Burgi K.: Determine maintenance hoof trimming by observing movement. 10 th International symposium on Lameness in Ruminants, Casino Lucerne, Switzerland, pp , Stefanowska J., et al: Impact of floor surface on behaviour and foot lesions in cattle. Rapport 98-09, Instituut voor Milieu - en Agritechniek, imag-dlo, Wageningen, Zeddies J., et al: Ökonomische Aspekte des Einsatzes von Tierarzneimitteln und tierärztlichen Behandlungen. Der praktische Tierarzt 78, Heft 1, S ,

9 Figures Figures 1, 2 and 3: KSL-mat (Gummiwerk KRAIBURG) 1: Bottom view 2:Top view 3: Profile Figure 4: functional claw 16 Figure 5: Caudal lick amount/20 active animals/h caudal lick no slipping 0 hard (1) yield (2) hard (3) slipping Slatted floor 283

10 EFFECTS OF A RUBBER-SLAT SYSTEM ON CLEANLINESS, FOOT HEALTH, AND BEHAVIOR IN TIED DAIRY COWS Christer Bergsten 1, Jan Hultgren 1 Swedish Dairy Association 1, Swedish University of Agricultural Sciences 2 Introduction Infectious claw disorders are of great importance all over the world. These diseases are highly dependant on the hygienic conditions in places where the cows stand and walk. The contagiousness of pathogens is also important and infections are more likely to spread in systems where the animals are in frequent contact with each other, e.g. loose housing. The most common contagious claw diseases causing lameness in a UK study were: interdigital phlegmon (foot rot) and digital dermatitis (Mortellaro's disease, hairy heel warts). In total, sole ulcer was the most common disease [5]. However, in Swedish tie-stalls, footrot and digital dermatitis are rarely seen; instead the most common hygiene related diseases are interdigital dermatitis and heel horn erosion [1]. Free-stall systems are rapidly increasing, but still 75% of Swedish dairy cattle are kept in tie-stalls when housed. With less time spent per animal, a higher production and more manure produced, cleanliness and hygiene-related foot lesions is a major problem. In many countries, electric cow-trainers are an efficient means to keep tie-stalls clean from manure and reduce foot lesions. Although foot disorders are of great animal-welfare and economical concern [3], electric cow-trainers were banned by the Swedish animal welfare legislation in 1995, mainly for ethical reasons. Thus, new technical solutions are needed to improve the hygiene in modern dairy systems. A new rubber-slat system for tied dairy cows, with the ability to drain faeces and urine, was studied in a Swedish experimental herd. The aim of the study was to evaluate effects of the rubber-slat system on animal cleanliness, foot health and behavior. Material and methods The study included 42 Swedish Red and White cows, which were kept tied in traditional longstalls (2.20 m) equipped with rubber mats. In a long-stall, the cow can be closed out from the manger, while in a short-stall (1.80 m) she has availability to the manger 24 hours. In 21 stalls, the rearmost 0.74 m of the solid stall floor had been replaced with nine rubber-coated 53 mm wide slats, divided by 29-mm slots (Fig. 1). A similar system had previously been used for more than 20 years in a commercial herd of tied beef cattle. Short (0.50 m) or long (0.85 m) stall dividers were placed between every 2 nd cow. The cows were observed during two consecutive housing periods. At the beginning of each housing period, the animals were listed in order of parity and number of days in milk; every 2nd cow on the list was tied on each type of floor (quasi-random allocation). No cows were moved between the floor types during the housing periods and culled cows were successively replaced by heifers in late pregnancy. The cleanliness was assessed weekly (year 1) or bi-weekly (year 2) by observations of the hind part of the body. The extension of contamination with manure was assessed visually. Claw measurements and foot health of the rear feet were assessed at claw trimming in the beginning, middle, and end of each housing period, including the year prior to 1 Contact at: Swedish Dairy Association, P.O. Box 234, SE Skara; Tel: ; Fax: ; Christer.Gergsten@hmh.slu.se 284

11 the study (year 0). Interdigital dermatitis, sole lesions (hemorrhages and/or ulcers) and heel horn erosion were scored (0, 1) by the same person, except for the last trimming of years 0 and 2. The rising, lying-down, and resting behavior for 12 matched cow-pairs, one cow from each floor type, were studied during two 24-hour periods, using a time-lapse video technique. The effects of floor type on cleanliness and foot health was analyzed using logistic regression and a GEE technique (GENMOD procedure, SAS Institute Inc., 1997), to account for clustering on the cow level (assuming an exchangeable correlation structure). Statistical analysis of the difference in behavior between the two floor types was done using the Student's t test for matched pairs or the sign test (JMP 3, SAS Institute Inc., 1998). Results The risk of getting dirty on the rubber-slatted floor was significantly lower as compared to the solid stall floor (OR 0.12 for hind feet when short stall-dividers were used, 0.39 for hind legs and 0.38 for thighs and udder). The risk of foot diseases of rear feet at trimming was significantly lower on the rubber-slatted floor (OR 0.23 for dermatitis, 0.09 for heel horn erosion, and 0.34 for sole lesions). The prevalence of dermatitis and heel horn erosion showed a clear seasonal variation, reflecting an effect of time of exposure to imperfect housing conditions (Fig. 2). Cows on the rubber-slatted floor lay down more readily than cows on the solid floor, spending on average 23% less time preparing to lie down (20.8 vs s; P=0.026). Cows on rubber slats also slipped less frequently during rising. There was some evidence of a preference for a solid floor when lying, the relative time spent resting in an adjacent stall being 14% units longer on the rubber slats than on the solid floor (67 vs. 53%; P=0.026). The total average daily resting time was 12.2 h (55.2 min per resting bout). No differences in health (udder health, trauma) were observed between the floor types. Discussion The improved cleanliness on the rubber-slatted floor in the present study resulted in less dermatitis and heel horn erosion, similar to the effect of electric cow-trainers in an earlier Swedish trial [2]. Epidemiological studies have also showed dirtiness to be associated with papillomatous digital dermatitis [6]. The preventive effect of the rubber-slatted floor on sole lesions was unexpected, because the cows were kept on rubber floors in both floor groups. However, it has been proposed that heel horn erosion can provoke sole ulcers, because the support of the bulbs is reduced and the load on the rear part of the sole is greater in a cow affected by heel horn erosion [7]. Moreover, the rubber-coated slats were somewhat elastic in their construction, which might have been beneficial for the lasting of the elastic tissues of the claws, which seem to have deteriorated in cows with sole ulcers [4]. In tie-stalls, long feeding times often make it very difficult to scrape the stalls in pace with the contamination with manure. Although the rubber-slatted floor is rather expensive, this study indicates that its benefits in terms of improved cleanliness and foot health could counterbalance the investment. The cows behavior (rising, lying down or resting) was not affected negatively by the rubber-slatted floor system, as has been advocated for electric cow-trainers. The results were found to be in accordance with the requirements of pre-testing of new technical systems and equipment for livestock, as regulated by the Swedish statute on animal protection, and the rubber-slatted floor system has now been approved. 285

12 Conclusions Tie-stalls equipped with the rubber-slatted flooring improved the cleanliness of the animals and reduced the prevalence of hygiene-dependent dermatitis, heel horn erosion and sole lesions. In the design of future dairy systems, the hygienic conditions of the floors must be considered. References 1. Bergsten C: Kofot 2000: Promoting hoof trimming and hoof health in Swedish dairy herds. in 2000 Hoof Health Conference. Duluth, Minnesota: American Hoof Trimmers Assoc Bergsten C. and Pettersson B.: The cleanliness of cows tied in stalls and the health of their Hooves as influenced by the use of electric trainers. Prev Vet Med 13: , Kossaibati M.A. and Esslemont R.J.: The costs of production diseases in dairy herds in England. Vet J 154:41-51, Lischer C.J., Ossent P., et al: The significance of the suspensory mechanism of the third phalanx and its fat bodies in the pathogenesis of sole ulcers in cattle, Part I: macroscopic findings. in 11 th Int. Symp. on Disorders of the Ruminant Digit & Int. Conf. on Bovine Lameness. Parma, pp , Murray R.D., Downham D.Y., et al: Epidemiology of lameness in dairy cattle: Description and analysis of foot lesions. Vet Rec 138: , Rodriguez Lainz A., et al: Case-control study of papillomatous digital dermatitis in southern California dairy farms. Prev Vet Med 28: , Toussaint Raven E., Haalstra R.T. and Peterse D.J.: Cattle foot care and claw trimming. Ipswich: Farming press. Pp 128,

13 53 7 Rubber slats 0.74 m Uri Dung channel C 2.20 m Rubber mat Figure 1. Section of the rear part of the long-stall, showing the rubber-slatted floor over the dung channel with urine drainage. 80% 60% 40% 20% 0% Year 0 Dermatitis Year 1 Year 2 80% Heel Year 2 horn - repetition 3 erosion % Year 1 Year 2 40% Year 0 20% 0% Solid floor Rubber slats Figure 2. Prevalence of dermatitis and heel horn erosion in tied dairy cows on rubber slatted and solid floors during three housing seasons. 287

14 THE LONG-TERM EFFECT OF HOUSING PRE-CALVING ON SOLE AND WHITE LINE HAEMORRHAGES Laven R.A., 1 Livesey C.T. 2 ADAS Bridgets Dairy Research Centre, Martyr Worthy, Hants SO21 1AP 1 Veterinary Laboratories Agency, Weybridge 2 Introduction Abnormal hoof conformation results in significant increases in sole and white line lesions (Livesey et al. 2000a). Underfoot conditions have a significant impact on hoof conformation and health. Livesey et al. (2000b) showed that rearing heifers in straw yards resulted in significantly poorer hoof conformation at calving and a significantly higher severity of sole and white-line haemorrhages in the early post partum period. As a result of these findings the examination of these heifers were extended to assess whether the effect persisted into the second lactation. Materials and Methods Sixty, 12 month-old, heifers were split into two housing groups: Rearing on straw with no access to concrete until after calving or in cubicles during the same period. Both groups were housed in the same cubicle yard after calving (see Livesey et al 2000b for more details). From 12 weeks post partum all had been managed together as part of the main commercial herd at ADAS Bridgets. Thirty heifers were re-examined 40 weeks after calving, 15 at second calving and 30 three months later. Measurements were made of toe angle, toe length, and the prevalence and severity of sole and white-line haemorrhages (Greenough and Vermunt 1994). Results and Discussion The results are summarised in Tables 1 to 3. No significant effects of rearing yard on any parameter were found except on white line haemorrhage score at 40 weeks when the straw reared cows had a significantly lower lesion score. Despite the very large differences seen in the first three months after calving (Livesey et al. 2000b), no effect of rearing yard on hoof conformation was seen. The effect of rearing on lesion score was very similar with no effect on the severity of sole or white line haemorrhages except for a significant effect on white line haemorrhages alone 14 weeks after calving. However, this effect was small compared to that seen after the first calving and was in the opposite direction. These data show that the heifers reared on straw were able to compensate during their first lactation so that there was no significant difference in hoof conformation or haemorrhages after second calving. This suggests that the conclusions of Livesey et al. (2000b) that rearing heifers on soft surfaces is undesirable are incorrect. However, claw horn disease is multifactorial and environment after first calving can have a major impact on lesion development (Livesey et al. 2000a). None of the heifers in this study developed white line 1 Contact at: ADAS Bridgets Dairy Research Centre, Martyr Worthy, Hants SO21 1AP; ; Richard.laven@adas.co.uk 288

15 disease or sole ulcer, probably because of good management. In a poorer environment, it is probable that exacerbation of the post partum haemorrhages, which were more prominent in the straw-reared heifers, would have led to an increase in claw horn diseases in that group, which would have had long-term consequences. Acknowledgements This research was funded by MAFF References 1. Greenhough P. and Vermunt J.: 8 th International Symposium on the Ruminant Digit, Banff pp , Livesey, et al: 11 th International Symposium on the Ruminant Digit, Parma pp , 2000(a). 3. Livesey, et al: 11 th International Symposium on the Ruminant Digit, Parma pp , 2000(b). Table 1: Effect of rearing yard on lesion score, conformation, growth, and wear (mean SEM) at 40 weeks post partum Lesion score Housing Sole White Line Toe Angle Toe Length Cubicles 1.6 (±0.39) 2.0 (±0.32) 40.9 (±0.96) 73.3 (±0.87) Straw 1.5 (±0.36) 2.0 (±0.37) 43.1 (±0.67) 72.9 (±0.94) Table 2: Effect of rearing yard on lesion score, conformation, growth, and wear (mean SEM) at second calving Lesion score Housing Sole White Line Toe Angle Toe Length Cubicles 1.0 (±0.37) 0.9 (±0.32) 39.9 (±1.15) 84.3 (±1.46) Straw 0.2 (±0.17) 1.2 (±0.37) 39.2 (±1.6) 83 (±2.68) Table 3: Effect of rearing yard on lesion score, conformation, growth, and wear (mean SEM) at second calving + 14 weeks Lesion score Housing Sole White Line Toe Angle Toe Length Cubicles 1.4 (±0.39) 1.4 (±0.22) 45 (±1.4) 84 (±2.0) Straw 1.5 (±0.36) 0.7 (±0.24) 42 (±1.77) 83.4 (±2.0) 289

16 THE EFFECT OF ENVIRONMENT PRE-CALVING ON THE HOOF CONFORMATION OF FIRST LACTATION HEIFERS Livesey C.T 2, Laven R.A. 1 ADAS Bridgets Dairy Research Centre, Martyr Worthy, Hants SO21 1AP 1 Veterinary Laboratories Agency, Weybridge 2 This paper reports the effects on hoof conformation of rearing heifers on straw yards as compared to cubicles. Previous reports have reported the effect on hoof growth and wear, hoof haemorrhages and toe angle. Sixty pedigree heifers were reared from 12 months of age until calving in one of two environments: Straw with no access to concrete or a straw bedded cubicle yard. The hind feet of each heifer were examined at the beginning of the study, midpregnancy, approximately six weeks before predicted data of calving and in weeks one and 13 of lactation. In addition to the measurements described previously (Livesey et al 2000), photographs were taken at each examination so that more specific measurements of hoof conformation could be made, including heel depth and toe length. Analysis of these data confirmed the previous analysis which suggested that the hoof conformation of the cubicle reared heifers did not change significantly within the first three months post partum, but the heifers reared on the straw, calved down with hooves that had very different conformation from the cubicle reared heifers (in particular heel height was considerably lower). The hoof conformation of the straw reared heifers also changed significantly during the first three months post partum, becoming much more similar to the conformation of the cubicle reared heifers. 290

17 INTENSIFICATION OF BUFFALO LEADS TO SIMILAR LAMANITIC LESIONS AS SEEN IN CATTLE A. Shakespeare, 1 M. Hofmeyr 2 and C. Bergsten 3 Faculty of Veterinary Science, Onderstepoort, South Africa, 1 Kruger National Park, South Africa, 2 Department of Animal Environment and Health, Skara, Sweden 3 Commercial game farming has become big business in southern Africa. Breeding disease-free buffalo, to satisfy this market, not only requires large financial inputs but also various forms of intensification of these animals. These buffalo are often restricted to smallish camps or bomas, not only to protect and isolate them from the elements and disease, but to encourage more successful breeding and survival of the young. Because of this space restriction, natural grazing and exercise is severely limited and supplementary feed has to be offered. Consequently these animals are farmed in far from ideal conditions and certain problems obviously result, with lesions as a result of chronic laminitis being but one. Buffalo calves in one project, born between December 1999 and April 2000 were monitored for just over a year. One batch were removed from their natural mothers at birth and were fostered 3 to a Jersey cow for the entire period. These calves, although still suckling, had ad lib access to lucerne (alfalfa) and eragrostis teff as did their mothers who were also given a total mix ration to sustain their milk production. These calves grew at least a third bigger than the second batch and appeared at lot softer. None of these calves had any hoof lesions although the medial hind claw appeared to rotate slightly inwards. This could be normal and probably corrects itself later and has yet to be recorded. The second batch of buffalo calves were left to suckle their natural mothers until weaning at 5 to 6 months. The calves had had access to ad lib lucern (alfalfa) and eragrostis teff as was offered to their mothers. At weaning, in addition, to the previous diet, the calves were offered ad lib citrus pulp. Within a few months, all these calves showed lesions associated with chronic laminitis such as overgrown hooves (abnormal shapes ie., buckled anterior margin with rising tow; growth rings; high heel and convex sole [as described by Toussant Raven]), sole haemorrhages, slipper foot, double soles and white line bleeding. This second group of buffalo calves were subsequently darted a number of times and curatively trimmed back as close as possible to the normal. A few adult buffalo cows had to immobilized and examined due to lameness. Excessively overgrown hooves had to be trimmed back whilst those with white line disease and sole ulcers once rectified needed to have blocks fixed to the sound medial hind claws. In all these cases, the soft sandy ground and limited area for exercise, plus the commercial diets offered to these wild animals undoubtedly encouraged the hoof problems detected. Economic considerations will preclude the rectification of one or all of the predisposing causes so an increase in hoof problems in buffalo, as seen in cattle, is expected in the future. 291

18 THE INFLUENCE OF HOUSING SYSTEMS AND FEEDING REGIMES ON THE CLAW CONDITION AND THE OCCURRENCE OF KERATINOPATHOGENIC FUNGI IN FATTENING BULLS Ch. Stanek, P. Karall, J. Frickh*, M. Keller and J. Spergser Clinic of Orthopaedics in Ungulates, University of Veterinary Medicine Vienna, Austria, and Federal Research Farm Königshof*, Lower Austria In central Europe, various housing systems, including older tying stall systems, boxes with solid or slatted floors and in increasing frequency outdoor paddocks, are common for fattening bulls. Also different feeding regimes are applied. Comparatively little is known about the influence of the different systems on the claw condition and on time dependent development of pathological changes. Analyses of the occurrence of keratinopathogenic fungi should lead to a better understanding of the pathogenesis of poor claw horn quality and claw diseases. 60 young Simmenthal bulls, purchased on auctions of the Austrian breeding organisations, were divided into two groups on one large research farm: one group was kept in a tying stall, the other group was kept in an open paddock. Each of these groups was subdivided into two subgroups of 15 bulls each. One subgroup of each housing system was fed a pelleted complete feed ad lib, the other two subgroups were fed with maize silage ad lib and concentrate added. The observation period followed an accommodation period, started on day 75 and ended with slaughter on day 450 of the life of the fattening bulls (Karall, 2001). Claws were scored using the system proposed by Bosman et al. (1989), modified by Stanek (in Brandejsky et al., 1994). Using this score, factors like condition and contour of the wall, condition and relief of the sole, white line separation, severe pathological changes and heel erosio are recorded for each of the 8 claws and summarised in a single numerical figure, allowing the comparison of a variety of changes. Adaptation of the Boosman score included a higher weighting of severe pathological changes like sole ulcers or apical necrosis of the claw. The bulls were claw-scored 3 times in regular intervals, the 4 th claw scoring procedure was performed immediately after the slaughter. For mycological examination, horn samples are harvested in the coronary region after slaughtering and deep frozen. Thereafter they were cultivated on Sabouraud-glucose agar. Behaviour data, data on slaughter yield and meat quality factors were analysed as well, but are not included in this report. The main results of claw scoring are presented in table 1: 292

19 Table 1: Mean values of claw scores and residual standard (s e ): SG 1 SG 2 SG 3 SG 4 s e Score Score Score b a b a Score b a b a Total score b a b a SG 1: pellets / Tying stall; SG 2: pellets / paddock; SG 3 Maize silage and concentrate / Tying stall; SG 4 Maize silage and concentrate / paddock. a, b : indicating significant difference p < 0.05 Claw soundness was influenced by various factors. The feeding regime did not affect the claw score during all 4 recordings of the observation period, whilst a significant influence of the housing regime could be observed (SG 1 and SG 3 vs. SG 2 and 4). Fattening bulls kept on tying stalls developed a significant deterioration of the claw condition mainly in the second part of the study. In the tied-stall groups, the claw score increased from mean 18.2 up to 112.4, whilst in the paddock group the increase was significantly lower from 17.7 to The most significant deterioration was found with respect to severe pathological conditions, also mainly in the second part of the whole observation period. The occurrence of groove formation on the wall was quite low in both groups. The frequency of solear haemorrhages was quite low under both housing regimes, whilst the frequency of white line separations was significantly higher in the tied stall groups. Despite the frequent removal of manure, heel erosions developed more frequently in the tying stall system in the last part of the observation period. In the bulls kept in the tying stall, the heel erosion score rose from 0.1 to 8.8, whilst in the paddock kept group the increase of changes was comparatively low (from 0.0 to 0.87) Severe pathological changes were observed in the tying stall group in a significant high rate (Severe lesions score 33.5 vs. 7.6 in the paddock group) Results of mycological examination revealed apathogenic, facultative and keratinopathogenic fungi in a high percentage in both housing groups. 12 different mould fungi and dermatophytes were observed, 8 of them accepted as non-keratinopathogenic in literature. Four keratinopathogenic genera (Alternaria sp., Goetrichum sp., Scopulariopsis sp., Trichophyton sp.) were found. There was no evident correlation with the general condition of the claw. On the other hand, the percentage of claws affected with keratinopathogenic fungi was significantly higher in the paddock group. 293

20 Average daily weight gain was higher in both paddock subgroups compared with the tying stall system (1461 g vs g), silage feeding was superior to the complete pelleted ratio. In combination with the superior behaviour possibilities of the paddock group, the paddock system offers a superior economical result, the needs of animal behaviour can be fulfilled much better. References (a complete list of references may be provided upon request) 1. Boosman R, et al: Arteriographical and pathological changes in chronic laminitis in dairy cattle. Vet Quart 11: , Brandejsky F, Stanek Ch, et al: Zur Pathogenese der subklinischen Klauenrehe beim Milchrind: Untersuchungen von Klauenstatus, Pansenstatus und Blutgerinnungs-faktoren. Dtsch. Tierärztl. Wschr. 101:68 71, Karall P: (The influence of two different housing systems and two different feeding systems on claw quality, behaviour, slaughter yield and meat quality in fattening bulls; German) Dr. med. vet. Thesis, Univ Vet Med Vienna,

21 MANAGING HERD LAMENESS - A PERSPECTIVE FROM DOWN UNDER J.J. Vermunt 1 and D.P. Twiss Institute of Veterinary, Animal and Biomedical Sciences, Massey University, New Zealand Abstract The management of a lameness problem, involving up to 10 percent of a 500-cow, springcalving, dairy herd is described. An on-farm investigation identified the farm tracks and the handling of cows by the stock persons as the two main risk factors for this particular problem. Recommendations were made on the patient handling of cows. However, improving the farm tracks had to be postponed until the cows were dried off. Once weekly, the lame cows were observed while walking, locomotion scored and treated (for scores >2).There appeared to be no age predilection. The predominant lesion was septic pododermatitis due to sole or white line penetration. Overall, hind limbs were more often affected than front limbs. The lesions, however, were fairly equally distributed between lateral and medial claws, which reflected the traumatic nature of most of the lesions. Introduction New Zealand has a unique, year-round, pasture-based dairying environment, with an average herd size of well over 250 cows. Lameness causes significant economic losses, and is one of the dairy industry's main welfare issues. The average annual incidence of lameness is around 8-10 percent, varying markedly between herds and between areas. Many herd managers treat cows for lameness themselves, and veterinarians only deal with 25 percent of lamene sscausing lesions. Of these, greater than 75 percent are of traumatic origin (Chesterton, 1988; Tranter & Morris, 1991). Major contributing factors to lameness in New Zealand dairy cattle include farm tracks (their length, width, quality, design, construction, maintenance and use), dairy shed yards, the length of time spent on these concrete yards, the manner in which cows are moved from the paddock to the shed, and the manner in which cows are handled during the milking process (Chesterton et al, 1989; Malmo & Vermunt, 1998 & 1999). Nutrition, age, stage of lactation, conformation, genetics and rainfall also play a role, albeit minor (Vermunt, 1992). All these factors need to be taken into account when developing a programme to minimise dairy cattle lameness. This paper describes the management of a lameness problem, involving up to 10 percent of a 500-cow, spring-calving, Friesian dairy herd. Case Presentation Three neighbouring dairy farms had been joined to form one bigger dairy unit using a newlybuilt, 36-aside herringbone shed. In the spring of 2000, a systematic on-farm investigation identified the farm tracks and the handling of cows by the stock persons as the two main risk factors for this particular herd's lameness problem. Recommendations were made on the patient herding and handling of cows both before and during milking. Although improving the farm tracks was identified as a priority, this had to be postponed until the cows were dried off in the autumn / early winter of Contact at: Massey University, Private Bag , Palmerston North 5320, New Zealand; Phone: + 64 (6) ; Fax: + 64 (6) ; J.J.Vermunt@massey.ac.nz 295

22 As a rule, lame cows were separated from the milking herd and kept in paddocks adjacent to the dairy shed, so they did not have to walk long distances to pasture. On some days, the total number of lame cows was as high as 50. Managing such a large number of lame cows involved once weekly visits by one or two veterinarians. Cows that had been detected by the farm manager as being lame and that had not been treated before, were observed while walking and a locomotion score allocated (0 = no abnormality of gait; 1 = lameness hardly noticeable; 2 = slightly lame; 3 = markedly lame; 4 = affected limb not or hardly weight bearing). Each cow was examined as she moved on the concrete yard towards or away from the observer for about metres at a normal pace. Those with a score of 2 or less were returned to the nearby lame cow paddock to be rested and were milked only once a day. For the other cows, the site of the lameness was determined as they moved around on the concrete. Cases of hind limb lameness were lined up for treatment in the bails of the herringbone shed. Front limb lameness was treated with the cow restrained in a crush. The lame limb was examined and the lameness causing lesion identified by paring away a thin layer of horn from the weight-bearing surface of both digits. The predominant lesion was septic pododermatitis due to sole or white line penetration. Treatment consisted of providing free drainage, removing all necrotic and underrun horn, and applying a Cowslip to the sound claw. About 80 percent of lame cows had a Cowslip fitted; some cows needed two on different limbs. The number of animals treated at each visit varied from 6 to 22, and seemed to be positively correlated to the amount of rainfall. There was no obvious age predilection, with both heifers and mature cows being affected. Lame cows were returned to the main herd when the manager considered them completely sound. Antibiotics were administered when lesions were either deep-seated, or if the cause of lameness was interdigital necrobacillosis. Cows that developed septic arthritis of the distal interphalangeal joint were culled. Overall, hind limbs were more often affected than front limbs. The lesions, however, were fairly equally distributed between lateral and medial claws. This reflected the traumatic nature of most of the lesions encountered, being the result of a chance event rather than a systemic condition. Discussion The types of lameness causing lesions are different to those found in most studies carried out in the Northern Hemisphere. Sole bruising and septic pododermatitis due to sole or white line penetration are commonly reported findings in lame dairy cows in New Zealand. The lesions and consequent lameness seen in this herd appear to result from traumatic injury and bruising/infection of the sole corium. The fact that the lesions were fairly equally distributed between lateral and medial claws also adds support to the argument of trauma being the main inciting factor. Under New Zealand conditions, the long distances walked to pasture, wet weather conditions during early lactation, and - in this particular case - excessive walking/standing on hard surfaces and unsuitable materials used for track surface construction are likely to be the major predisposing factors involved. Although the figures of the incidence of lameness in New Zealand dairy herds vary widely between studies (2-38%), there can be little doubt that lameness causes significant economic 296

23 losses to the dairy industry. It is not possible to accurately assess the total loss caused by lameness. In addition to the costs of treatment, milk withdrawal (if required) and extra man hours spent managing lame cows, there are intangible losses such as decreased milk production, reproductive performance and bodyweight, premature culling and replacements costs. A decade ago, Tranter & Morris (1991) assessed the treatment costs to amount to NZ $12.50 per lame cow, excluding extra farm labour input. Evidently, this is considerably less than the mean total cost of Aus $43.00 per case, as estimated by Harris et al (1988) for dairy cattle in south-western Victoria, Australia. There can be little doubt that the cost figure will be significantly higher for the present herd because most lame cows had a Cowslip applied as a part of their treatment protocol. Therefore, it can be concluded from these figures that steps to reduce lameness will increase farm profitability. The present approach greatly assisted the herd manager in developing a sound understanding of lameness, as it occurs in New Zealand dairy cattle, its treatment, control and prevention, and it could be used as a model for other similar herd lameness problems. References 1. Chesterton RN, et al: Environmental and behavioural factors affecting the prevalence of foot lameness in New Zealand dairy herds - a case-control study. NZ Vet J 37: , Chesterton RN: Understanding and dealing with the lame dairy herd. Proceedings of the Seminar of the Dairy Cattle Society of the New Zealand Veterinary Association, pp , Harris DJ, Hebert CD, et al: The incidence, cost and factors associated with foot lameness in dairy cattle in south-western Australia. Aust Vet J 65: , Malmo J, Vermunt JJ: Lameness in dairy cattle - A review (part 1). J Aust Assoc Cattle Vet 8:23-31, Malmo J, Vermunt JJ: Lameness in dairy cattle - A review (part 2) - Farm track construction. J Aust Assoc Cattle Vet 9:15-18, Tranter WP, Morris RS: A case study of lameness in three dairy herds. NZ Vet J 39:88-96, Vermunt JJ: Subclinical laminitis in dairy cattle. NZ Vet J 40: ,