Risk factors for tail lesions in undocked fattening pigs reared on Swiss farms.

INTRODUCTION: Tail lesions caused by tail biting are a major welfare and economic concern in fattening pigs. The aims of this study were to describe the prevalence and incidence of tail lesions in undocked pigs on individual animal level during the fattening period, to elucidate potential risk factors associated with tail lesions, and to describe the stockpersons' attitudes towards tail biting on Swiss farms. Thirty-eight farms were visited three times during the fattening period (beginning, mid-point, end). During each farm visit, tail lesions were scored on 30-126 individually marked pigs per farm (total: 2209 pigs), information on potential risk factors for tail lesions was recorded, and a standardized interview with the farmer was conducted to explore his/her opinion on tail biting. Potential risk factors were defined by indices when adequate, and their influence on the occurrence of tail lesions was analyzed using mixed effects logistic regression models. During the first and the second half of the fattening period, on average 14,1 and 15,4 pigs, respectively, out of 100 developed new tail lesions or aggravation of old lesions. The risk for new or aggravated tail lesions increased with higher scores for a «disease index¼ and with increasing group size, and it decreased with higher space allowances and with restrictive compared with ad libitum feeding. The prevalence of tail lesions on arrival was not associated with the incidence of tail lesions in the first and the second half of the fattening period, neither at farm level nor at pen level. In the interviews, farmers expressed their interest in getting professional advice on how to reduce tail biting on their farms. In conclusion, our study identified several risk factors for tail lesions in undocked fattening pigs indicating that the incidence of tail lesions could be reduced by improving animal health and housing conditions.

INTRODUCTION: Les lésions de la queue causées par morsure sont un problème majeur de bien-être et d'économie chez les porcs d'engraissement. Les objectifs de cette étude étaient de décrire la prévalence et l'incidence des lésions de la queue pendant la période d'engraissement chez les porcs non écaudés au niveau de chaque animal, d'élucider les facteurs de risque potentiels associés aux lésions de la queue et de décrire les attitudes des éleveurs à l'égard des morsures de queue dans les exploitations suisses. Trente-huit exploitations ont été visitées trois fois pendant la période d'engraissement (début, mi-parcours, fin). Lors de chaque visite, les lésions de la queue ont été notées sur 30 à 126 porcs marqués individuellement par l'exploitant (total: 2209 porcs), des informations sur les facteurs de risque potentiels de lésions de la queue ont été enregistrées et un entretien standardisé avec l'éleveur a été mené pour connaitre son avis sur les morsures de queue. Les facteurs de risque potentiels ont été définis par des indices lorsqu'ils étaient adéquats et leur influence sur la survenue des lésions caudales a été analysée à l'aide de modèles de régression logistique à effets mixtes. Pendant la première et la deuxième moitié de la période d'engraissement, en moyenne 14,1 et 15,4 porcs, respectivement, sur 100 ont développé de nouvelles lésions de la queue ou une aggravation d'anciennes lésions. Le risque de nouvelles lésions de la queue ou d'aggravation augmentait avec des scores plus élevés pour un «indice de maladie¼ et avec l'augmentation de la taille du groupe et il diminuait avec des allocations d'espace plus élevées et avec une alimentation restrictive par rapport à l'alimentation à volonté. La prévalence des lésions de la queue à l'arrivée n'était pas associée à l'incidence des lésions de la queue dans la première et la seconde moitié de la période d'engraissement, ni au niveau de l'exploitation ni au niveau des boxes. Dans les entretiens, les agriculteurs ont exprimé leur intérêt à obtenir des conseils professionnels sur la façon de réduire les morsures de queue dans leurs exploitations. En conclusion, notre étude a identifié plusieurs facteurs de risque de lésions de la queue chez les porcs d'engraissement non écaudés indiquant que l'incidence des lésions de la queue pourrait être réduite en améliorant la santé animale et les conditions de logement.

Body size in relation to cubicle dimensions affects lying behavior and joint lesions in dairy cows.

Adequate cubicle dimensions are important for dairy cows to allow for species-appropriate lying behavior. Even though cow body size has increased in the last 2 decades, the cubicle dimensions of housing systems built many years ago have not been adjusted on most farms. Therefore, cows may be impaired in their lying behaviors, and thus the present study aimed to determine the influence of the ratio of body size to cubicle dimension on lying behavior and joint lesions. We investigated the lying behavior of 144 cows with withers heights of 140 to 163 cm on 8 Swiss dairy farms. Among the farms, the cubicle bed length varied from 187 to 200 cm and lunge space length varied from 47 to 202 cm. Specific behaviors of lying down and standing up movements, as well as lying positions, were observed on 3 d per farm. As outcome variables, the occurrences of these behaviors were calculated as proportions in relation to the respective total number of observations per cow. In addition, the presence of joint lesions was scored once. Data of the individual cows were analyzed in relation to the given cubicle dimensions on the farms by mixed-effects models. The bed length ratio [bed length (cm) on the farm/withers height (cm) of the observed cow] and the lunge space ratio [lunge space length (cm) on the farm/withers height (cm) of the observed cow] were used as explanatory variables. An increase in the bed length ratio was associated with decreased proportions of lying down movements with (1) repeated head pendulum movements, (2) repeated stepping with front legs, and (3) hitting against cubicle elements; decreased proportions of standing up movements with (1) shifting backward, (2) hesitant head lunge movements, and (3) hitting against cubicle elements; and an increased proportion of lying positions without physical contact with cubicle elements. An increase in the lunge space ratio was associated with a decreased proportion of standing up movements with sideways directed head lunge movements. Furthermore, an increase in the bed length ratio decreased the proportion of cows with tarsal joint lesions. To summarize, the lying behavior of large-framed cows was clearly modified given the cubicle dimensions in use on the study farms. In view of the consistency of the obtained results, we recommend adjusting the dimensions of cubicles so that they are suitable for cows whose body size meets the breeding goals of the farm.

Moderate lameness leads to marked behavioral changes in dairy cows.

Lameness is one of the most prevalent diseases affecting the welfare of cows in modern dairy production. Lameness leads to behavioral changes in severely lame cows, which have been investigated in much detail. For early detection of lameness, knowledge of the effects of moderate lameness on cow behavior is crucial. Therefore, the behavior of nonlame and moderately lame cows was compared on 17 Swiss dairy farms. On each farm, 5 to 11 nonlame (locomotion score 1 of 5) and 2 to 7 moderately lame (locomotion score 3 of 5) cows were selected for data collection in two 48-h periods (A, B) separated by an interval of 6 to 10 wk. Based on visual locomotion scoring, 142 nonlame and 66 moderately lame cows were examined in period A and 128 nonlame and 53 moderately lame cows in period B. Between these 2 periods, the cows underwent corrective hoof trimming. Lying behavior, locomotor activity, and neck activity were recorded by accelerometers (MSR145 data logger, MSR Electronics GmbH, Seuzach, Switzerland), and feeding and rumination behaviors by noseband sensors (RumiWatch halter, ITIN + HOCH GmbH, Liestal, Switzerland). Furthermore, visits to the brush and the concentrate feeder, and the milking order position were recorded. In comparison with nonlame cows, moderately lame cows had a longer lying duration, a longer average lying bout duration, and a greater lateral asymmetry in lying duration. Average locomotor activity, locomotor activity during 1 h after feed delivery or push-ups, and average neck activity were lower in moderately lame cows. Eating time and the number of eating chews (jaw movements) were reduced in moderately lame compared with nonlame cows, whereas no effect of moderate lameness was evident for ruminating time, number of ruminating chews and boluses, and average number of ruminating chews per bolus. Moderately lame cows visited the concentrate feeder and the brush less frequently, and they were further back in the milking order compared with nonlame cows. In conclusion, nonlame and moderately lame cows differed in a biologically relevant way in many of the behavioral variables investigated in this study. Therefore, the use of these behavioral changes seems to be promising to develop a tool for early lameness detection.