Vivi Pedersen

A note on the relationship between the behavioural response of lactating sows to humans and the survival of their piglets

Abstract The objective of this study was to examine the relationships, based on unit averages, between the behavioural responses of lactating sows to humans and the performance of sows in 25 farrowing units at a large commercial farm. The behavioural responses of 25 sows in each farrowing unit were observed at 2–4 and 16–18 days of lactation and a correlation analysis, using unit averages, was used to examine the behaviour–productivity relationships. Moderate and significant between-unit correlations were found between the behavioural response of lactating sows at days 16–18 to an approaching experimenter and the percentage of stillborn piglets. Units in which test sows were quicker to withdraw in the presence of the experimenter had a higher stillbirth rate than those units in which a reduced withdrawal response was displayed. The withdrawal response of sows in the close presence of the experimenter accounted for about 18% of the variance in percentage of stillborn piglets. While this study was a preliminary one examining the potential for the human–animal relationship to affect the performance of sows in the farrowing shed, the results indicate that high levels of fear of humans by sows may affect the survival of their piglets. The possible mechanisms whereby fear may affect piglet survival are considered. Clearly further research is warranted because of the important practical implications of this negative fear–productivity relationship on animal performance and welfare.

Effects of whole-year nest boxes on cortisol, circulating leucocytes, exploration and agonistic behaviour in silver foxes

An experiment was carried out for a period of 2 years, using 50 silver fox vixens kept in cages with nest boxes, and 50 vixens kept in barren wire cages without any sort of equipment. At the end of the experiment, the animals living with access to nest boxes had lower base levels of cortisol and eosinophils, and higher base levels of lymphocytes. They also were less fearful towards humans and more active/ explorative in an open field test. It was concluded that these animals were less stressed than those living without nest boxes, a result that could have practical implications for the welfare of foxes during everyday life at the farm.

Long-term effects of different handling procedures on behavioural, physiological, and production-related parameters in silver foxes

Fifty-one silver fox vixens, subjected to three different handling treatments as cubs (no-handling, gentle or forced handling), were studied for long-term effects on behavioural, physiological and production-related parameters in a one and a half year period following the last handling session. As juveniles, the animals were exposed to three different behavioural tests at 18, 22, 28, and 32 weeks of age. Both forcibly and gently handled animals showed reduced fear responses compared with nonhandled controls in test situations involving close contact with humans (P 0.05). Early post-weaning handling made foxes less fearful towards humans. Forced handling seemed somewhat superior to gentle handling as a means to produce animals which, in the long term, adapted better to the farm environment both behaviourally and physiologically. Non-handled control animals suffered from long-term stress as reflected by high levels of fear responses and enlarged adrenals. Thus post-weaning handling may be beneficial in the long term for the wellbeing of farmed foxes. When applied as a management routine, handling had no significant influence on later production-related parameters and was not considered an economic risk.

Effects of Family Housing on Behaviour, Plasma Cortisol and Performance in Adult Female Mink (Mustela vison)

Various behavioural, physiological and production-related parameters were examined in 200 adult female pastel and pearl mink either family housed in three-room cages with no weaning or housed singly in one-room cages after normal weaning procedures. Scanning observations of behaviour and use of the cages were performed in the nursing period and several parameters related to reproduction were registered. The adult female mink were weighed when kits were 16 weeks old (September) and again at pelting time (November). Blood samples were collected from all adult female mink in September at which time the teat condition and fur damage were evaluated. After pelting, bite marks on the leather side of the skin were counted, fur damage was graded after severity and the fur size was measured. Some positive consequences of being family housed were revealed. The familyhoused adult female mink showed a lower level of stereotypes and a higher level of defensiveness and curiosity than the adult female mink in one-room cages during the nursing period. In September and November, family-housed adult females were heavier than singly housed adult females. However, most of the physiological or production-related parameters pointed in a negative direction for familyhoused adult female mink. Reproductive success was somewhat reduced, although not significantly. Plasma cortisol levels were elevated in September, indicating higher levels of stress in these females. They showed a generally poor teat condition in September, with a high proportion of swollen or bitten teats. A high proportion of these adult females showed fur damage in both September and November, and a high number of bite marks was found on the leather side of the skins of these females, indicating that family housing had a high cost for the adult female mink. In conclusion, there seem to be some benefits, at least on the behavioural level, in keeping adult female mink in three-room cages during the nursing period, but both physiological and production-related parameters indicated that the welfare of the adult female mink was threatened if she was continuously cohoused with her litter past the normal age of weaning.

Early experience with the farm environment and effects on later behaviour in silver Vulpes vulpes and blue foxes Alopex lagopus

Seventy-one silver fox and 141 blue fox cubs were exposed to constant visual contact with the farm environment from the age of 2 to 8 weeks. The exposure consisted in opening a door in the nest box facing the feed gang-way. Control cubs (33 silver and 77 blue foxes) were reared in similar but closed nest boxes. All cubs were tested at the age of 12-16 weeks and again at the age of 23-28 weeks; during these tests the behavioural responses of the foxes towards a human being were recorded. Both tests showed that in the two species, the early experience with the farm environment reduced the fear responses of the foxes towards humans. The conclusion of the study was that early visual experience with the farm environment makes the foxes better adapted to captivity, including the presence of humans.

Daytime use of various types of whole-year shelters in farmed silver foxes (Vulpes vulpes) and blue foxes (Alopex lagopus)

Abstract The use of four different whole-year shelters was examined in 50 silver- and 50 blue-fox vixens in the autumn and winter months from November 1987 to February 1988 and from August 1988 to March 1989. Observations were not carried out during breeding. All vixens had free access to a top box with an underlying shelf, a side box and an open box. The location of the vixens was determined by the use of regularly performed scan samplings with a sampling interval of 10 min. After a short period of becoming accustomed to the shelters both species showed a preference for the shelf and the top box. Silver foxes spent most time on the shelf, whereas blue foxes spent most time in the top box. Blue foxes were observed in the shelters twice as frequently as silver foxes. When disturbed, most of the silver foxes fled from the experimenter to the opposite side of the cage; some fled into the top box. Most of the blue foxes fled into the top box when disturbed and some fled into the side box. It was suggested that these differences between species were reflecting greater general timidity in the blue fox or different behavioural strategies towards danger in the two species.

Preference for various nest box designs in farmed silver foxes (Vulpes vulpes) and blue foxes (Alopex lagopus)

Nest box choice experiments were carried out outside the breeding season on adult silver and blue fox vixens with no previous permanent nest box experience. Nest boxes were varied in height of placement, number of rooms, presence of entrance room or platform and light conditions. Only one parameter was varied in any one experiment. Both fox species clearly preferred an elevated multi-room nest box; while silver foxes showed preference for boxes supplied with a platform, blue foxes preferred boxes with an entrance room. There was no significant box preference with respect to light conditions. The possible welfare implications of the preferences are discussed.