Feeding Stalls Research Articles

The Role of Environmental Enrichment and Back Fat Depth in the Intensity of Aggressive Behavior Performed by Sows during the Establishment of the Dominance Hierarchy.

For sows introduced into new groups, the aggressive behavior associated with establishing a social hierarchy represents a period of severe stress. The aim of this study was to investigate the effect of providing sows with an improved pen environment (straw in racks and ropes) on aggressive behavior after mixing and to understand the role played by sow back fat thickness and parity order. At 29 d post-service, sows were mixed into IMPROVED or CONTROL pens with individual feeding stalls (6 groups/treatment, 20 sows/group). Aggressive behavior was recorded for 2 h at mixing (T0) and 24 h (T1) and 3 weeks post-mixing (T21). Overall, the sows in the CONTROL pens performed more fighting behavior compared to the IMPROVED sows (p < 0.001). This difference was significant only at T21 (p < 0.001). Additionally, the sows in the CONTROL pens generally initiated more aggressive behaviors than the sows in the IMPROVED pens (p = 0.02). The sows with a low back fat thickness initiated more aggressive behaviors, but parity had no significant effect on any of the aggressive behaviors. These results indicate a beneficial effect of improvements to the pen environment on the aggression performed by group-housed sows between the time of mixing and three weeks later. The effect was reduced on the day of mixing, which is in accordance with the necessity for sows to employ aggression to establish the dominance hierarchy.

Area and Resource Utilization of Group-Housed Horses in an Active Stable.

Simple SummaryHorses are increasingly being kept in group stables where they are given the opportunity to move freely and to contact conspecifics. This study examined how the horses of a large group move in an active stable and which areas or resources they use over a period of 7.5 months with the help of linear mixed models. Therefore, a grid with the size of 3 × 3 m per square was applied. The horses used, on average, 53.2 ± 19 different squares per hour. It was shown that observation day (p < 0.001) and covariate age (p < 0.001) had significant effects on squares visited per hour. Sex (p = 0.30) and breed (p = 0.65) had no significant effects. A large variation in the squares visited per hour was determined for the individual horses. Most frequently visited were the individual resources, such as the feed stalls or lying halls. An open tarp skin lying hall was preferred over a metal hall. The shelters were only partly popular. An overview of the usage frequency of the paddock could be created by using heatmaps. Overall, specific conclusions about the use of individual areas and potential for improvement could be pointed out.The aim of this study was to analyze the utilization of different stable areas of a total of 52 group-housed horses as well as their preferred stable parts and the use of resources. The study was situated in a “HIT Active Stable®” in Northern Germany for a period of 227 observation days. After dividing the whole farm area in a grid of 3 × 3 m, the dataset was examined with and without the pasture area. Furthermore, linear mixed models were applied. On average, horses used 53.2 ± 19 different squares per hour. The observation day (p < 0.001) and the covariate age (p < 0.001) had significant effects on the different squares visited per hour. No significant effects were found for sex (p = 0.30) and breed (p = 0.65) as only geldings and no stallions were part of the group and the distribution of the breeds was unfavorable. The random effect animal showed that the horse-individual estimates from −19.2 to 17.6 different squares visited per hour were quite large. Furthermore, it could be shown that the horses used resources such as feed stalls with a frequency of up to 0.14% more than other paddock areas without resources. Open lying halls with tarp skin were also preferred over the metal hall. The shelters were only partly popular. Use could be visualized with the help of heat maps. This study gives a good overview of the use of individual areas and resources and possible improvements.

Assessment of RumiWatch noseband sensors for the quantification of ingestive behaviors of dairy cows at grazing or fed in stalls

The RumiWatch System (Itin+Hoch GmbH, Liestal, Switzerland) is a sensor system that enables quantification of ingestive behaviors of cattle that may be useful, amongst other things, for estimating dry matter intake. There are currently multiple versions of the RumiWatch Converter software used to convert the recorded data into specific animal behaviors through the use of algorithms. The objective of this research was to evaluate the use of RumiWatch System noseband sensors for quantifying the number of prehension bites and mastication chews in grazing and stall-fed dairy cows using RumiWatch Converter software versions 0.7.3.36 (RWC36) and 0.7.4.13 (RWC13). Two experiments using lactating Holstein-Friesian dairy cattle were conducted. In Experiment I, ten cows grazed perennial ryegrass pasture (Lolium perenne L.) in individual plots that measured 35 m2, with a pasture mass of 2500 kg DM/ha and pasture allowance of 28 kg DM/d. In Experiment II, 14 cows were offered 16 kg DM/d of perennial ryegrass pasture silage in individual indoor feed stalls. In both experiments, ingestive behaviors were quantified with the jaw movement halters and through visual observation using video recordings. The performance of the RumiWatch Converter software was evaluated through Lin’s concordance correlation coefficients with video observation. For grazing cows, there was greater concordance between the RumiWatch System and video observation for the number of prehension bites (0.94 for RWC36 and 0.75 for RWC13) than for the number of mastication chews (0.20 for RWC36 and 0.14 for RWC13). In cows fed in stalls, there was also greater concordance for the number of prehension bites (0.54 for RWC36 and 0.64 for RWC13) than for the number of mastication chews (0.46 for RWC36 and 0.58 for RWC13). However, the RWC36 was more accurate for quantifying feeding behaviors of grazing cows than the RWC13, while for stall fed cows the reverse was true. Overall, both RumiWatch Converters were better at quantifying prehension bites in grazing cows than in stall fed cows, but better at quantifying mastication chews in stall fed cows than grazing cows. These data enable a new understanding of the how these RumiWatch sensors should best be used for measuring cows' feeding behaviors in different feeding systems.

Comparison of the Productivity of Primiparous Sows Housed in Individual Stalls and Group Housing Systems.

Simple SummaryRecently, South Korea amended the respective laws and will be enforcing that sows must be kept in group housing after 6 weeks from insemination by the year 2030. Accordingly, the comparison of productivity of sows in individual stalls and group housing systems was investigated in order to provide information on group housing systems for sows to pig farms. Primiparous sows were divided into four groups and housed in equal number in pen stalls, in short stalls with non-gated feeding stalls, in free access stalls, or with access to electronic sow feeders after 8 weeks from artificial insemination. Sows were transferred to farrowing crates at 110 days of gestation. No differences were found in sow productive performance, reproductive performance, and colostrum composition among housing types. Therefore, it was concluded that group housing systems could be used to replace individual stalls in commercial sow units.This study was conducted to provide commercial pig farms with information about group housing systems for sows in accordance with the amendment of the prohibition law for individual stalls for sows in South Korea. Therefore, this experiment was performed to compare the effects of individual stalls (IS) and group housing systems (GS) on the productivity of sows to investigate the feasibility of replacing individual stalls with group housing systems in commercial sow units. Forty primiparous sows (Landrace × Yorkshire; 210.67 ± 2.22 kg average initial body weight) were randomly assigned to four treatments with restricted feeding after 8 weeks from artificial insemination. The four treatments were (i) individual stalls (IS; housed in pen stalls), (ii) short stalls (SS; sows housed in pens with non-gated feeding stalls), (iii) free access stalls (FAS; a non-competitive housing system), and (iv) electronic sow feeders (ESF; used with radio frequency identification technology to allow individual sow management without individual confinement). All sows were transferred to farrowing crates at 110 days of gestation. There were no differences in sow productive performance, reproductive performance, and colostrum composition between IS and GS and among GS. The considered GS did not negatively affect any productivity parameters of primiparous sows compared with IS; the GS could replace IS in commercial sow units.

Trough half empty: Pregnant sows are fed under half of their ad libitum intake

AbstractPregnant (dry) sows (Sus scrofa) are fed a rationed amount of feed to maintain healthy weight and production but this does not satisfy their hunger. This study measured the extent of feed restriction compared to sows’ desired intake. Forty-seven Large White × Landrace sows were housed in small groups with straw bedding and individual feeding stalls. Following three days on a standard ration of 2.5 kg, they were offered 10 kg a day of commercial dry sow feed for three days, split into four 2.5-kg meals a day which enabled individual intakes to be measured. This quantity was effectively ad libitum (maximum daily intake 9.4 kg). Mean (± SEM) intake per day over the three ad libitum days was 5.67 (± 0.24) kg, compared to the 2.5-kg standard ration. The ration thus provides less than half (44.1%) of sows’ desired intake. Behaviour on their third rationed day was compared with behaviour on the third day of ad libitum. Eating rate and the display of hunger-related behaviours, particularly following the morning feed, was greater under ration feeding; sows spent more time in the food stall and less in the straw bed, and more time active rather than resting. During ration-feeding sows also chewed and nosed more at straw bedding and pen equipment and used the drinker more after their morning meal than when they were fed ad libitum. Eating rate on the last rationed day was positively correlated with feed intake on each of the ad libitum days. Despite an EU requirement for fibre to be added to diets to ameliorate this problem, and the provision of straw bedding, hunger resulting from food restriction remains a welfare concern for dry sows.

Effect of continuous access to feeding stalls during mixing on behavior, welfare, and performance of group-housed gestating sows in different social ranks

This study was conducted to evaluate a strategy of using feeding stalls to protect low-ranking sows in group-housing systems. Sows (n = 150, parity 1–9) were mixed at weaning in pens of 15 sows. Control pens allowed sows to access feeding stalls for 1 h of feeding daily during the initial 2 d after mixing. Treatment pens allowed sows to access feeding stalls continuously. Social rank was determined based on outcomes of aggressive interactions among sows after mixing. Low-ranking sows used the feeding stalls more frequently (P &lt; 0.01) than high-ranking sows during the initial 6 h after mixing. Continuous stall access reduced frequency of aggressive interactions (P = 0.05) and, consequently, reduced skin lesions (P = 0.05) of sows in the pen. Neither continuous access to stalls nor social rank affected performance of sows. These results suggest that low-ranking sows used feeding stalls as hiding spaces to escape from aggressive interactions during mixing, which reduced skin lesions caused by aggression and improved the welfare of sows in the group-housing system studied.

Effects of group housing on sow welfare: a review.

Factors that have been shown to impact the welfare of group-housed sows are discussed in this review. Floor space allowance markedly affects sow welfare. In addition to quantity of floor space, the quality of space is important: spatial separation between sows can be provided with visual or physical barriers and stalls. Whereas 1.4 m/sow is insufficient, further research is required to examine space effects in the range of 1.8 to 2.4 m/sow in more detail. The period immediately after mixing has the most pronounced effects on aggression and stress, and therefore, well-designed mixing pens offer the opportunity to reduce aggression, injury, and stress while allowing the social hierarchy to quickly form. Because hunger is likely to lead to competition for feed or access to feeding areas, strategies to reduce hunger between meals through higher feeding levels, dietary fiber, or foraging substrate should be examined. However, feeding systems, such as full-body feeding stalls, can also affect aggression and stress by providing protection at feeding, but deriving conclusions on this topic is difficult because research directly comparing floor feeding, feeding stalls, and electronic sow feeder systems has not been conducted. Familiar sows engage in less aggression, so mixing sows that have been housed together in the previous gestation may reduce aggression. Although there is evidence in other species that early experience may affect social skills later in life, there are few studies on the effects of early "socialization" on aggressive behavior of adult sows. Genetic selection has the potential to reduce aggression, and therefore, continued research on the opportunity to genetically select against aggressiveness and its broader implications is required. Most research to date has examined mixing sows after insemination and knowledge on grouping after weaning is limited.

Der Einfluss erhöhter Fressstände auf das Fressverhalten von Milchkühen

The performance level of high yielding cows can only be guaranteed by high quality forage and high feed intake. An about 15–20 cm elevated and 160 cm long feed stall with rubber flooring doesn’t only offer undisturbed meals but also a yielding and dry standing surface. In a pilot stable with 130 dairy cows (German Simmental) the feeding alley was subsequently equipped with elevated feed stalls. The results show that animals frequented the feeding barn less often while the duration of single meals prolonged. The specific behavioural changes differed depending on milk yield and number of lactation.

Risk factors associated with leg disorders of gestating sows in different group-housing systems: A cross-sectional study in 108 farrow-to-finish farms in France

Group-housing, rather than individual-housing systems, is mandatory for gestating sows in the European Union (2008/120/EEC). However, leg problems occur more frequently in group-housing than in individual-housing systems and are a welfare and health concern. A cross-sectional study involving 108 farms in western France was carried out to see whether the type of the 4 main group-housing systems (i.e. large groups with electronic feeder station in stable or in dynamic groups, small groups in walk-in lock-in stalls or partial feeding stalls), and other husbandry practices, were associated with leg disorders. In each farm, the sows were examined visually for claw lesions, scored for lameness and their breeding characteristics were recorded. Lameness was positively correlated with heel lesions and dewclaw lesions. A concrete slatted floor, as compared to straw, was a major risk factor (unadjusted relative risk (RR)=9.9; 95% confidence interval (95% CI): 4.4–34.5). Walk-in lock-in stalls were found to be the most protective system. A logistic regression model was used to identify those factors which significantly increased the risk of leg problems. These factors were: housing in large groups (RR=1.5; 95% CI: 1.1–2.4), dirty floors (RR=1.6; 95% CI: 1.0–2.9), high level of ammonia (RR=1.5; 95% CI: 1.1–2.1), severely restricted feeding particularly during the last stage of pregnancy (RR=1.5; 95% CI: 1.0–2.1) and a high number of sows per stockman (RR=1.5; 95% CI: 1.0–2.4).

Effect of rubber slat mats on the behaviour and welfare of group housed pregnant sows

This study evaluated the effect of flooring, lameness, body and limb lesion scores on postural and spatial behaviour of gestating sows. Sixty-four sows were kept in groups of four in pens with four solid concrete floored feeding stalls and a concrete fully slatted group area from 4 weeks after service. The slats were either left uncovered (CON; n=8 groups) or 10mm thick rubber slat mats were affixed (RUB; n=8 groups). Lameness (0=normal to 5=severe), limb (environmentally induced lesions, e.g. callus, wounds, swellings; scored according to severity—0=normal to 6=severe) and body (aggression induced lesions; scored according to severity—0=normal to 5=severe) lesions were scored on days 1, 8, 25, 50 and 75 relative to entering the experiment. Additionally video recordings were made of the groups for 24h on the same days which were sampled instantaneously every 10min. An index of the proportion of time spent in (1) different postures (standing, ventral [VL] and lateral lying [LL] and total lying [VL+LL]); (2) locations (stalls or group area), (3) posture by location and (4) number of postural changes was calculated. Sows were categorized as non-lame (score ≤1) or lame (score ≥2). Median scores were calculated for body and limb lesions and were classified as ≤median or >median. Lameness, limb and body lesions were analysed using logistic binomial regression. Behavioural variables were tested for normality and analysed using mixed model equations. Flooring did not affect lameness, body lesion scores, time spent in each posture or the index of postural changes (P>0.05). RUB sows spent more time in the group area (76.3 vs. 53.3±5.8%; P<0.01) and lay more there (80.0 vs. 62.4±5.3%; P<0.05) compared with CON sows. Sows with scores >median for wounds on the limbs spent more time LL (41.2 vs. 48.3±3.6%; P<0.05) and less time VL (36.3 vs. 29.9±2.9%; P<0.05). On the other hand, sows with body lesion scores >median spent more time VL (29.9 vs. 36.3±2.9%; P<0.05). Lame sows stood less and lay more (P<0.05) in the feeding stalls. When sows had access to rubber flooring they spent more time in the covered area and lay more there compared with sows in pens where the concrete slats were bare. This reflects the preference of group housed sows for a comfortable surface for lying during pregnancy. Other sow factors such as body and limb lesions and lameness status are also related with lying behaviour.

Influence of permanent use of feeding stalls as living area on ammonia and greenhouse gas emissions for group-housed gestating sows kept on straw deep-litter

In pig production, the interest for litter systems in relation with animal welfare and the ban by 2013 in the EU of individual accommodations for gestating sows could promote the group-housing of gestating sows on deep-litter. However, compared to slatted-floor systems, few data are available on the gaseous emissions associated with the different modalities of rearing sows on deep-litter. In this study, two modalities were compared: group housing on a 3m2/sow deep-litter or on a 1.8m2/sow deep-litter plus 1.2m2/sow concrete floor. In both cases, sows were fed in individual feeding stalls (1.2m2/stall) but the access was limited at feeding time in the first case and permanent in the second one.Three successive batches of 10 gestating sows were used. Each batch was divided into 2 homogeneous groups randomly allocated to one of two treatments: fully (3m2/sow) or partly (1.8m2/sow) straw-based deep-bedded floor. The groups were kept separately in two identical rooms with same volume and same surface, equipped with five individual feeding stalls in contact with a pen of either 9 or 15m2 deep-litter. The feeding stalls were equipped with front feeding troughs and rear gates allowing or not permanent access to the stalls outside of feeding times. Between each batch, the pens were cleaned. In both rooms, ventilation was automatically adapted to maintain a constant ambient temperature. The gas emissions (nitrous oxide, methane, carbon dioxide, ammonia and water vapour) were measured 3 times (weeks 2, 5 and 8 of stay) during 6 consecutive days by infrared photoacoustic detection.Sow performance was not significantly affected by floor type. With sows kept on partly bedded floor, gaseous emissions were significantly greater for methane (12.76 vs. 9.90g/d.sow; P<0.001), carbon dioxide (3.12 vs. 2.90kg/d.sow; P<0.01) and water vapour (4.70 vs. 4.03kg/d.sow; P<0.001), and significantly lower for nitrous oxide (3.14 vs. 6.12g/d.sow; P<0.001) and CO2 equivalents (1.24 vs. 2.10kg/d.sow; P<0.001) compared to sows housed on fully bedded floor. There was no significant difference for ammonia emissions (8.36 vs. 7.45g/d.sow; P>0.05).From the present trial in experimental rooms, it can be concluded that keeping group-housed gestating sows on partly straw bedded floor with permanent access to the concrete feeding stalls compared to fully straw bedded floor did not significantly influence animal performance and NH3-emissions, and decreased CO2eq-emissions (−40%). This decrease was observed owing to an important decrease of N2O-emissions (−49%).

Ammonia and greenhouse gas emission from group-housed gestating sows depends on floor type

The ban by 2013 in the EU of individual accommodations for gestating sows and the renewed interest for litter systems could promote in the future the group-housing of gestating sows on litter. But what are the environmental impacts of this rearing technique? To answer this question, a study was scheduled to quantify pollutant gas emissions (nitrous oxide –N 2O–, methane –CH 4–, carbon dioxide –CO 2– and ammonia –NH 3–) according to floor type in the raising of group-housed gestating sows. The trial was carried out in experimental rooms located at Liège University (Belgium). Three successive batches of 10 gestating sows were used for this trial. Each batch was divided into 2 homogeneous groups randomly allocated to one of two treatments: concrete slatted floor or straw-based deep litter. The groups were kept separately in two identical rooms equipped with a pen divided into a lying area (slatted floor or deep litter) and five individual feeding stalls. The feeding stalls were equipped with front feeding troughs and rear gates preventing access to the stalls outside of the feeding time. Between each batch of sows, the pens were cleaned. In both rooms, ventilation was automatically adapted to maintain a constant ambient temperature. The gas emissions were measured 3 times (weeks 2, 5 and 8 of stay) during 6 consecutive days by infra red photoacoustic detection. Sow performance (body weight gain, backfat thickness, number and weight of piglets) was not significantly affected by floor type. With sows kept on slatted floor, gaseous emissions were significantly greater for NH 3 (12.77 vs. 9.05 g d −1 sow −1; P < 0.001) and CH 4 (10.12 vs. 9.20 g d −1 sow −1; P < 0.01), and significantly lower for N 2O (0.47 vs. 2.27 g d −1 sow −1; P < 0.001), CO 2 equivalents (0.44 vs. 0.94 kg d −1 sow −1; P < 0.001) and CO 2 (2.41 vs. 2.83 kg d −1 sow −1; P < 0.001) compared to sows housed on straw-based deep litter. There was no significant difference for water vapour emissions (3.25 vs. 3.21 kg d −1 sow −1; P > 0.05). In conclusion, the main environmental disadvantage of the deep litter system pointed to in this study was the greater N 2O-emissions and thus greater CO 2eq-emissions compared to slatted floor. However, the use of deep litter was related to reduced NH 3- and CH 4-emissions.

Risk factors for skin lesions on the necks of Norwegian dairy cows

Physical restrictions at the feed barrier may cause skin lesions, especially on the necks of cows. Thus, some aspects of the functionality of feed barrier design can be assessed by observing skin lesions on the necks of dairy cattle. In this study, 232 herds, mainly of the breed Norwegian Red (94%), were investigated between September 2006 and June 2007. The herds were categorized into 2 groups. One data set, based on 1,148 cows (115 herds), was from farms using feed barriers with post-and-rail designs (86 herds) and combinations of barriers (29 herds). The second data set, which included 1,168 cows (117 herds), was from farms using only vertical feed barriers such as tombstone, diagonal, and headlock. Skin lesions were observed on the necks of 21% of the 2,335 cows observed. Forty-two percent of cows had neck lesions in herds with post-and-rail barriers, whereas 4% of cows had neck lesions in herds with vertical barriers and 30% of cows had neck lesions in herds with a combination of both horizontal and vertical barriers. Alternating logistic regression was used to identify factors associated with skin lesions on the necks of cows. The estimates were transformed into odds ratios (OR). In herds in which post-and-rail design barriers were used, the following risk factors were associated with skin lesions: manger front lower than 63cm versus higher (OR=3.6), no feed stalls versus feed stalls (OR=10.9), mixed rations versus no mixed ration (OR=3.8), cows later than 30 DIM versus earlier (OR=1.9), cows with low milk production versus those producing 1,000kg higher (OR=1.4), feeding frequency of less than 3 times daily versus 3 and more times daily (OR=1.9), using only post-and-rail feed barriers (OR=1.8) versus using combinations, and farmer disagreement with the statement “animals experience physical pain as humans do” (OR=1.9) versus agreement. Diagonal barriers, categorized as vertical barriers, increased the association of skin lesions with increasing manger front heights. Feed barrier design was associated with skin lesions on the necks of cows, particularly for barriers of a post-and-rail design. To minimize the risk of neck lesions, the top rail height of post-and-rail barriers should be above 109cm, especially for cows taller than 126cm, and the manger front should not be lower than 63cm. Feed stalls, feeding frequency of 3 or more times daily, and the feeding of unmixed rations were also identified as preventive factors.

A flooring comparison: The impact of rubber mats on the health, behavior, and welfare of group-housed sows at breeding

Comfortable flooring may impact many aspects of an animal's welfare, including lying behavior, an animal's ability to change postures, and incidence of lameness and lesions. Therefore, we hypothesized that the addition of rubber mats to stalls of group pens would improve sow health, comfort and welfare during breeding. In this study, Landrace × Yorkshire sows (128) were mixed post-weaning and housed in pens of four. The pens contained a slatted group area and four feeding stalls. Rubber mats (measuring 1.83 m × 0.61 m × 1.27 cm) were added to the feeding stalls of half of the pens and rotated to the opposite pens for each replication. The behavioral time budgets of the sows were recorded throughout the experiment; lesion and lameness scores were collected prior to mixing and at the end of the experiment. Data were analyzed as repeated measures mixed models with post hoc Tukey tests. The pattern of behaviors performed in the stall versus group area was different for mat and concrete treatments (REML: F 2,56 = 12.98; P < 0.001). Tukey tests revealed that only resting behaviors were affected. We then examined resting behavior in detail. Time spent in different resting postures (sternal versus lateral lying) differed between treatments (REML: F 1,30 = 4.92; P = 0.03), where sows on mats spent more time lying laterally ( P < 0.05) and performed more of their lying behavior in the stalls (GLM: F 1,22 = 14.88; P = 0.001) compared to sows on concrete. Additionally, sows stood up and laid down more frequently (GLM: F 1,30 = 13.53; P = 0.001) than sows on concrete. Warm temperatures reduced resting behavior in the stalls (REML: F 2,56 = 8.75; P < 0.001). Sows in matted pens had a lower total lesion score at the end of the experiment in comparison to sows in concrete pens (REML: F 1,30 = 5.03; P = 0.03). Lameness scores did not differ between treatments. These results imply that the provision of alternative comfort flooring may provide welfare benefits to breeding sows, though environmental temperature needs to be considered when providing rubber mats.

Relation between parity and feed intake, fear of humans and social behaviour in non-lactating sows group-housed under various on-farm conditions

AbstractThe number of group-housed, non-lactating sows is increasing rapidly in Europe. However, systematic information of the between-sow variation in animal welfare related factors under various on-farm conditions is lacking. Indicators of feed intake, fear of humans and social behaviour in non-lactating, group-housed sows were monitored in 14 herds. Regarding indicators of feed intake, the results revealed that back fat gain increased with increased parity number to a larger extent in group feeding than in individual feeding systems. Furthermore, behavioural observations showed that sows older than third parity spent significantly more time eating than younger sows during feeding in group feeding systems. With respect to indicators of social behaviour, first parity sows had significantly more skin lesions than older sows in herds with no escape possibilities (small group sizes and no feeding stalls), whereas second and third parity sows had the highest number of skin injuries in herds with escape possibilities. The results emphasise a need for management initiatives to consider the requirements of especially young sows in group housing. This is of particular importance in systems with small group sizes and group feeding systems.

Performance of gestating sows in bedded hoop barns and confinement stalls1

The effects of gestation housing systems on sow and litter performance were evaluated for 2.5 yr in southwest Iowa. Gestation housing system treatments were as follows: 1) individual gestation stalls in a mechanically ventilated confinement building with a partially slatted floor and a manure flush system and 2) group pens with individual feed stalls in deep-bedded, naturally ventilated hoop barns. In all, 957 litters from 353 sows were evaluated. Number of pigs born alive per litter differed for the 2 housing treatments (P = 0.002). Sows gestated in hoop barns gave birth to more live pigs per litter (10.0 +/- 0.2 pigs) than sows gestated in stalls (9.3 +/- 0.2 pigs). Preweaning mortality was not different for the 2 housing treatments (P = 0.70). Cross-fostering was done to equalize litter size within 24 h of birth, which resulted in an equal number of weaned pigs per sow (P = 0.50) regardless of gestation housing treatment. The weaning-to-breeding interval was different (P = 0.01), with sows kept in stalls (4.3 +/- 0.6 d) returning to estrus sooner than sows gestated in hoop barns (6.0 +/- 0.6 d). These results indicate that gestating sows can be housed as groups in deep-bedded hoop barns equipped with individual feeding stalls and will perform comparably to gestating sows housed in confinement systems with individual gestation stalls.

Impact of Gestation Housing System on Weaned Pig Production Cost

Construction and operating costs for two gestation housing systems were compared to assess their impact on cost per weaned pig produced. The systems compared were: 1) individual gestation stalls in a mechanically ventilated confinement building with slatted floor and 2) group pens with individual feed stalls in deep-bedded naturally ventilated hoop barns. Previous work has shown that reproductive performance of group-housed sows in hoop barns is equal to individually stalled sows, and for some measures, may be improved. Hoop barn gestation facilities can be constructed for 70% of the cost of typical confinement facilities with gestation stalls. Fuel and electricity use in mechanically ventilated gestation buildings is more than utility use in hoop barns, although bedding costs only occur in hoop barns. Assuming equal prolificacy, feed cost per pig weaned is 7% more for sows gestated in hoop barns, but total cost per pig weaned is 3% less for pigs produced by sows gestated as groups in hoop barns compared to pigs from individual stall gestation systems. When the reported increase (0.7 pigs/litter) in live pigs born for litters following hoop gestation was included in the cost analysis, the group housing in hoop barns for gestation resulted in a weaned pig cost that was 10% less than the cost of a weaned pig from the individual stall confinement system. In the upper Midwest United States, group housing of gestation sows in deep-bedded hoop barns may produce pigs at a lower cost than individual gestation stalls in confinement facilities if the bedded group housing system is managed optimally.

Feed Stalls Affect the Social and Feeding Behavior of Lactating Dairy Cows

The first objective of this study was to study the effects of increased bunk space on the frequency of aggressive behavior at the feed bunk and on feed access. The second objective was to determine whether the addition of partitions (feed stalls) between adjacent cows would provide additional protection while feeding, particularly for subordinate cows. Twenty-four lactating Holstein cows were subjected to each of 3 treatments in 3 successive 10-d treatment periods using a 3×3 Latin square design. The treatments tested were: 1) 0.64m of feed bunk space/cow, 2) 0.92m of feed bunk space/cow, and 3) feed stalls (0.87m of feed bunk space/cow with feed stall partitions separating adjacent cows). Time-lapse video was used to quantify the feeding and standing behavior, as well as the aggressive behavior (displacements) displayed by the cows at the feed bunk. To meet our first and second objectives, we compared data from the 0.64 m/cow treatment with that from the 0.92 m/cow treatment, and data from the 0.92 m/cow treatment with that from the feed-stall treatment, respectively. Total daily feeding time increased when feed bunk space was increased from 0.64 to 0.92 m/cow. Further, the time spent standing in the feeding area while not feeding and the frequency of aggressive interactions at the feed bunk decreased when more bunk space was provided. The addition of feed stalls resulted in more pronounced effects compared with when cows had 0.92 m/cow of bunk space. The feed stalls also forced cows to change the strategy by which they displaced others from the feed bunk, forcing them to also initiate contact at the rear of the animal they were displacing rather than only from the front and side, as in the other 2 treatments. Further, when the cows were provided with additional feeding space, particularly when combined with feed stalls, those cows with lower social status at the feed bunk experienced the greatest decreases in the number of times they were displaced per day. The results indicated that providing increased feed bunk space, particularly when combined with feed stalls, will improve access to the feed and reduce competition at the feed bunk, particularly for subordinate cows.

Extensive bedded indoor and outdoor pig production systems in USA: current trends and effects on animal care and product quality

The objective of this review paper is to document extensive bedded indoor and outdoor pig production in the United States, which has expanded due to growing niche markets for natural and organic pork. Bedded hoop (tentlike) barns are used for finishing pigs and gestating sows. Seasonal outdoor farrowing and some indoor bedded farrowing systems coupled with group lactation are used also. Most natural pork markets require outdoor or bedded settings, no subtherapeutic antibiotics or growth promotants, no animal by-products in feed, and a family farm production setting. Hoop-fed pigs have more backfat, smaller loin area, and lower carcass yield compared with confinement-fed pigs. Hoop-fed pigs have fewer aberrant behaviors and handle easier than confinement pigs. Health is similar except for an increase in internal parasites in hoop-fed pigs. Pigs in hoops are in larger groups than in confinement. Biosecurity in hoops is more difficult due to incoming bedding and open access. Hoop-fed pig performance varies depending on thermal environment, which is closely related to season and climate. Bedded hoop barns with individual feeding stalls provide an acceptable environment for gestating sows. Overall, product quality differences are relatively minor compared with wide variations in rearing environment for extensively reared pigs.

Assessing long-term behavioural effects of feeding motivation in group-housed pregnant sows; what, when and how to observe

Main aim of this study was to elucidate behavioural elements that can be used as a tool to measure satiety in group-housed pregnant sows. In addition, the best time (time of day and time on treatment) and observation method were addressed. In two batches, eight groups of five artificially inseminated nulliparous sows were housed in 17.9 m 2 pens with feeding stalls. Sows were fed at 07:30 and 15:00 h and either had access to a restricted amount of a low-fibre diet (R) or an unrestricted amount of a high-fibre diet (40% sugarbeet pulp) during 30 min (S). Behaviour was scored by focal sampling in five 3-week time periods since the start of the treatments, during 1 h after the morning meal and 1 h before the afternoon meal. All behavioural elements, that are potentially influenced by satiety were scored, including, e.g. social behaviours and tail postures. Data were reduced by excluding or combining behavioural states that had a variation coefficient larger than 100 or a mean appearance of less than 1% of the scoring-time in the R-group (pooled data). Remaining (groups of) behavioural elements that differed between treatments ( P<0.05) were considered to be relevant and were used to reveal relevant periods. Data of the selected periods ( P<0.05 for most selected elements) were used to analyse the morning and afternoon scoring separately. The states Inactive, Self-directed behaviour (combination of, e.g. Sham-chewing and Teeth-grinding), Substrate-directed behaviour (combination of, e.g. rooting and licking substrates), Standing, Moving and Lying lateral and the events Alert and Biting were selected and differed between treatments. In general, S-sows showed less activity than R-sows. Events did not differ between treatments in most separate periods and were, therefore, excluded from further analysis. Differences between treatments in the selected states were only found in the last four periods. Except for Moving (afternoon only) states differed between treatments both in the morning and the afternoon. Differences in the afternoon were, however, more pronounced. It is concluded that at least Inactive, Self-directed behaviour and Substrate-directed behaviour should be used in future ethological studies on satiety in group-housed pregnant sows. These can be scored by scan sampling. The postures Standing and Lying lateral are interesting as well. Observations from 6 weeks after the start of the dietary treatments are most useful and may be done just after feeding, but also several hours after feeding.