Impact of group housing of pregnant sows on health

Group housing of sows during gestation is mandatory in the EU since 2013. Compared to housing in individual crates, group housing allows the animals to express normal activity and behavior. The present paper discusses the impact of group housing on health, with emphasis on lameness, aggression and possible spread of infectious diseases. The prevalence of lameness is generally higher in sows housed in group than in sows housed individually. Floor space per sow, group size, pen design and flooring are the main factors of group housing involved in lameness development. Especially floor characteristics are important, and particular attention should be paid to the type, building material and quality of the floor, hygiene and the use of bedding such as straw or rubber mats. Aggression between sows is another critical issue in group housing systems. It occurs predominantly because of competition for access to a limited resource, or to establish a social hierarchy. Key factors to prevent aggression in group housing include gradual familiarization of unfamiliar animals, sufficient space and pen structure during initial mixing, minimizing opportunities for dominant sows to steal food from subordinates, provision of a good quality floor, environmental enrichment and use of straw bedding. Very scarce evidence-based information is available on the relationship between group housing and infectious disease. Compared to individual housing, sows in group housing have more nose-to-nose contact, and they have more oral contact with feces and urine. These factors could contribute to a higher or faster transmission of pathogens, but so far, there is no evidence showing more disease problems in group housing systems. In conclusion, in group housing systems, particular attention should be paid to prevention of lameness and aggression. Management is crucial but also feeding strategies, floor and bedding, and design of housing are very important as relatively minor adjustments may exert major effects on the animals.Peer reviewe

Locomotion disorders and skin and claw lesions in gestating sows housed in dynamic versus static groups

Lameness and lesions to the skin and claws of sows in group housing are commonly occurring indicators of reduced welfare. Typically, these problems are more common in group housing than in individual housing systems. Group management type (dynamic versus static) and stage of gestation influence the behavior of the animals, which in turn influences the occurrence of these problems. The present study compared prevalence, incidence and mean scores of lameness and skin and claw lesions in static versus dynamic group housed sows at different stages of gestation during three consecutive reproductive cycles. A total of 10 Belgian sow herds were monitored; 5 in which dynamic groups and 5 in which static groups were utilized. All sows were visually assessed for lameness and skin lesions three times per cycle and the claws of the hind limbs were assessed once per cycle. Lameness and claw lesions were assessed using visual analogue scales. Static groups, in comparison with dynamic groups, demonstrated lower lameness scores (P<0.05) and decreased skin lesion prevalence (24.9 vs. 47.3%, P<0.05) at the end of gestation. There was no difference between treatment group regarding claw lesion prevalence with 75.5% of sows demonstrating claw lesions regardless of group management. Prevalences of lameness (22.4 vs. 8.9%, P<0.05) and skin lesions (46.6 vs. 4.4%, P<0.05) were highest during the group-housed phase compared to the individually housed phases. Although the prevalence of lameness and skin lesions did not differ three days after grouping versus at the end of the group-housing phase, their incidence peaked during the first three days after moving from the insemination stalls to the group. In conclusion, the first three days after grouping was the most risky period for lameness incidence, but there was no significant difference between static or dynamic group management

Pathological findings in spontaneously dead and euthanized sows - a descriptive study

Background:A high rate of euthanized and spontaneously dead sows causes production losses and likely indicatesunderlying welfare problems. Identification of predisposing factors to on-farm deaths requires a thoroughunderstanding of the causes. Post-mortem examination is needed for a proper diagnosis. The aims of thisdescriptive study were to determine causes of spontaneous deaths and euthanasia in sows in a conveniencesample of Finnish herds and to describe pathological findings in the locomotor system and in teeth and gums.Results:This study described post-mortem findings in 65 sows found dead or euthanized on 15 farms. All but oneof the sows presented with two or more pathological findings. The majority of primary pathologic-anatomicdiagnoses (PAD-1) were inflammatory. The most prevalent diagnoses were arthritis and peritonitis (9% of sowseach). The locomotor system was the body part most commonly affected by lesions. Findings in the locomotorsystem unassociated with death were present in 85% of the animals, additionally 29% of PAD-1 s concerned thelocomotor system. The prevalence for both degenerative joint disease and tooth wear was 71%. Farmers had notedclinical signs within 30 days of death in every euthanized sow and in half of the spontaneously dead ones. Thefarmer’s impression of the cause of death agreed at least partly with the PAD-1 in 44% of the cases.Conclusion:Multiple pathologies were the norm in the present animals. This may indicate an extended course ofillness and therefore also an unnecessary delay in medical treatment or euthanasia. The prevalence and clinicalrelevance of the most common disorders, including degenerative joint disease and tooth wear, need to beelucidated.Peer reviewe