Alternative farrowing systems: design criteria for farrowing systems based on the biological needs of sows and piglets

Exploring effects of light intensity on sustainability indicators in finishing pig production

With an ongoing transition towards the use of Light Emitting Diodes, more knowledge is needed on which light settings optimise sustainability parameters in pig production. We studied the effects of four light intensities on social, environmental and economic sustainability indicators, including ammonia emissions, space use, pen fouling, weight gain, carcass quality, perception of the stockkeeper, costs of the light system, and use of drinking water, electricity and medicines. Light treatments included a low (45 lux), medium (198 lux) and high (968 lux) uniform intensity, and a spatial gradient treatment ranging from 71 lux in the front to 330 lux in the back of each pen. The latter treatment aimed to improve the space use of functional areas. A total of 448 growing-finishing pigs were studied on a commercial farm using two consecutive batches of four rooms containing eight pens with seven pigs. Light intensity influenced some aspects of space use and pen fouling. For example, the proportion of pigs lying in the resting area was higher in the high and medium light intensity treatment than in the low intensity and gradient treatment. Moreover, the high-intensity treatment resulted in more fouling with faeces in the feeding area compared with the low-intensity and the gradient treatment. Ammonia emissions were higher in the gradient than in the low intensity treatment (not measured in medium and high intensity treatment). Furthermore, light intensity did not affect weight gain, carcass quality, water use and medicine use. The stockkeeper was content to work in all light conditions, but slightly preferred the medium intensity due to optimal visibility. Concerning economic performance, the costs of the light system and electricity use increased in the following order: low intensity, gradient, medium intensity, and high intensity. In conclusion, contrary to expectation the spatial gradient did not notably improve space use or reduce pen fouling, but rather increased ammonia emissions in comparison with uniform light. This is likely because the gradient could not be applied in an optimal way in the existing housing conditions. Among the other sustainability indicators, mainly electricity use and costs of the light system differed per treatment. These aspects can be improved by further optimising the number of light sources needed per pen to achieve the targeted intensities.

Sow dimensions and loose-housed farrowing pen sizes on commercial piglet-producing farms in Sweden

International interest in loose-housed farrowing is growing and there are ongoing discussions within the European Union (EU) on new legal requirements. However, there is a lack of empirical data on loose-housed farrowing pen sizes and sow dimensions in commercial production. The aim of this study was to map and describe sow size and loose-housing farrowing pen size on commercial piglet-producing farms in Sweden. The study included 146 sows and 51 pen types on 35 medium sized to large Swedish piglet-producing farms (ranging from 106 to 1300 sows in production). Sow length ranged from 129 to 238 cm (mean ± SD 191.3 ± 19.3 cm) and sow height from 74 to 133 cm (86.7 ± 7.7 cm). Floor space occupied by the sow when lying down (length x height) ranged from 1.0 to 3.2 m2 (1.7 ± 0.3 m2). Pen length ranged from 259 to 415 cm (315.1 ± 24.3 cm), pen width from 188 to 245 cm (207.0 ± 10.7 cm), total pen area from 5.7 to 8.9 m2 (6.5 ± 0.5 m2), piglet corner area from 0.5 to 1.8 m2 (1.1 ± 0.4 m2) and area available for the sow (total area - piglet corner area) from 3.9 to 6.4 m2 (5.4 ± 0.6 m2). These results show that there is substantial variation in sow, pen and piglet corner size on commercial piglet-producing farms in Sweden. This poses a risk of mismatches between sow and pen size (pens too short in relation to sow dimensions), especially for older sows. These findings are of practical significance for animal welfare and production and emphasise the importance of designing loose-housed pens adapted to future sow, litter and piglet size.

Impact of farrowing system and prepartum nest-building material on nest-building behaviour and farrowing in sows

Farrowing crates are widely used as the main housing system for farrowing and lactating sows on commercial farms although they have a negative impact on sow welfare and behaviour. One of the main reasons for using farrowing crates is to reduce piglet mortality during farrowing and lactation. We compared the effects of temporary crating (TC) versus free farrowing (FF) with different nest-building materials on production and welfare measures. Sows were investigated using a 2 × 3 factorial design. Sows were allocated to two farrowing treatments: FF sows were not crated around farrowing, and TC sows were crated from 2 days before expected farrowing until 3 days after farrowing, when the crate was opened. In both farrowing treatments, the nest-building material was given from 7 days prior to farrowing as follows: (1) 1 L of straw twice per day, (2) 1 sheet of newspaper twice per day or (3) fastened jute fabric to the farrowing crate. The study consisted of two parts; part 1 included a total of 87 sows for data on piglet mortality and growth, and part 2 included data on nest-building and farrowing behaviour from a subset of these sows (n = 34). Farrowing treatment affected piglet mortality; FF sows had a lower number of stillborn piglets than TC sows (P = 0.04), but the number of crushed piglets was higher (P < 0.01). Nest-building material tended to have an impact on total number of crushed piglets (P = 0.08) and piglets that died during 3 days of lactation (P = 0.09). Litter growth was better in the FF group than in the TC group from piglet age of 1 day to 3 weeks (P = 0.04). Overall, little nest-building-related behaviour occurred, probably due to the small amount of nest-building material. The usability of the nest-building material varied with farrowing treatment; FF sows used newspaper most for nest-building, while TC sows used straw and jute fabric (P = 0.01). There were no differences in the piglet birth intervals or the farrowing duration. In conclusion, free farrowing can have positive effects on piglet growth but negative effects on piglet survival in early lactation. Different nest-building materials have different effects depending on the type of farrowing system.

Factors contributing to high performance of sows in free farrowing systems

BACKGROUND

Pressure to abolish farrowing crates is increasing, and producers are faced with decisions about which alternative system to adopt. For sow welfare, well designed free farrowing systems without close confinement are considered optimal but producers have concerns about increased piglet mortality, particularly crushing by the sow. Reporting accurate performance figures from commercial farms newly operating such systems could inform the transition process. This study investigated performance on three commercial farms operating four different zero-confinement systems, three of which were newly installed. A total of 3212 litters from 2920 sows were followed from farrowing to weaning over a three-year period with key performance indicators (KPIs) recorded. Mixed Models (LMMs, GLMMs) determined the influence of different factors (e.g. farrowing system, sow parity, management aspects) and litter characteristics on performance, including levels and causes of piglet mortality.

RESULTS

Piglet mortality was significantly influenced by farm/system. Live-born mortality ranged from 10.3 to 20.6% with stillbirths ranging from 2.5 to 5.9%. A larger litter size and higher parity resulted in higher levels of mortality regardless of system. In all systems, crushing was the main cause of piglet mortality (59%), but 31% of sows did not crush any piglets, whilst 26% crushed only one piglet and the remaining sows (43%) crushed two or more piglets. System significantly influenced crushing as a percentage of all deaths, with the system with the smallest spatial footprint (m2) compared to the other systems, recording the highest levels of crushing. Time from the start of the study influenced mortality, with significant reductions in crushing mortality (by ~ 4%) over the course of the three-year study. There was a highly significant effect of length of time (days) between moving sows into the farrowing accommodation and sows farrowing on piglet mortality (P < 0.001). The less time between sows moving in and farrowing, the higher the levels of piglet mortality, with ~ 3% increase in total mortality every five days. System effects were highly significant after adjusting for parity, litter size, and days pre-farrowing.

CONCLUSION

These results from commercial farms demonstrate that even sows that have not been specifically selected for free farrowing are able, in many cases, to perform well in these zero-confinement systems, but that a period of adaptation is to be expected for overall farm performance. There are performance differences between the farms/systems which can be attributed to individual farm/system characteristics (e.g. pen design and management, staff expertise, pig genotypes, etc.). Higher parity sows and those producing very large litters provide a greater challenge to piglet mortality in these free farrowing systems (just as they do in crate systems). Management significantly influences performance, and ensuring sows have plenty of time to acclimatise between moving in to farrowing accommodation and giving birth is a critical aspect of improving piglet survival.

Impacts of Farrowing Pen Design, Season, and Sow Parity on Litter Performance and Piglet Mortality

Piglet mortality during lactation is a significant concern in swine production, influenced by complex interactions involving sow, piglet, environmental, and management factors. While crushing by the sow may be the ultimate cause of piglet mortality, there are many factors influencing the outcome, including parity, thermal stress, and animal housing systems. New farrowing systems are continuously being developed; however, it is difficult for producers to make decisions without any scientific basis. This study aimed to assess the impact of different farrowing pen layouts on piglet performance, considering parity and season. A total of 546 sows and 9123 piglets were monitored across 36 lactation cycles. Sows were randomly assigned to three farrowing pen layouts (standard, diagonal, and offset) in three rooms (20 sows by room). All farrowing pens had the same space allocations (2.7 m by 1.8 m and 2.1 m by 0.6 m for the sow area). The three types of farrowing pens were blocked by position within the room. Piglet performance traits (percent of stillborns, percent of mortality, percent of overlays, and average daily weight gain: ADG) and sows traits (health and parity) were monitored following US Meat Animal Research Center (USMARC) procedures. Results indicated that treatment, parity, and season influenced some piglet performance traits. The offset farrowing pen had a lower percent of stillborns compared to the standard. No significant differences were observed between the diagonal crate and the other treatments. When evaluating high mortality sow (>two piglets), the offset and standard treatments had a lower percent of overlays. Piglets from first-parity sows had lower ADG than those from higher-parity sows. A higher percent of overlays were observed in Autumn and Summer compared to Spring and Winter, and Summer had lower average daily weight gain than other seasons. The results suggest that modifying the layout (offset), with sows placed further away from the heating source, can reduce the percent of overlays in sows with high mortality (>2 piglets). In addition, the influence of season on the piglet production traits demonstrated the importance of proper management of the environment, even in systems with a certain level of climatic control.

Sow serenity: automatic long-term measurement of lying behavior in crates and free-farrowing pens using 3D accelerometers

Accelerometers are useful in analyzing lying behavior in farm animals. The effect of the farrowing system on sow lying behavior has been studied around parturition, but not long-term. In a natural environment, sows increase activity 14 d post parturition, which we expected to be also evident in housed sows when they can move freely. The objective of this study was (1) to validate the methodology to automatically measure sow lying bouts and duration with accelerometers and (2) to apply it to crated and free-farrowing sows 24-h pre-parturition until weaning. We used videos with manual behavior coding as the gold standard for validation and calculated the agreement with an intraclass correlation coefficient (ICC), which was 0.30 (95% CI: -0.10 to 0.64) for the number of lying bouts. When transitional sitting bouts were excluded from the video dataset, the ICC for lying bouts increased to 0.86 (95% CI: 0.40 to 0.95). For lying duration, the ICC was 0.93 (95% CI: 0.26 to 0.98). We evaluated the effects of housing, day relative to parturition, and time of day on lying using the accelerometer data and linear mixed models. In crated sows, the number of lying bouts increased toward parturition, peaking at about five bouts per 6 h, and decreased to almost zero bouts after parturition. Then, it increased again (P = 0.001). In free-farrowing sows, the number of lying bouts gradually decreased from a high level towards parturition and was lowest after parturition. It remained constant, as in the crated sows, until day 15, when the number of bouts increased to eight bouts on day 20 (P = 0.001). Sows in both systems were lying almost all of the time between 18:00 and 00:00 hours and on all days (P = 0.001). The crated sows showed a very similar pattern in the other three-quarters of the day with a reduced lying time before parturition, a peak after parturition, reduced lying time from days 5 to 20, and an increase again towards weaning (P = 0.001). Free-farrowing sows had a similar pattern to the crated sows from 00:00 to 06:00 hours, but without the reduction in lying time from days 5 to 20. They showed an increase in lying time toward parturition, which remained constant with a final decrease toward weaning, especially during the day (P = 0.001). This study proves the accuracy of accelerometer-based sow lying behavior classification and shows that free-farrowing systems benefit lactating sows around parturition but also towards weaning in the nest-leaving phase by facilitating activity.

Effects of free farrowing system on the productive performance and welfare of sows and piglets

Regardless of international animal welfare regulations, most sows in production currently spend most of their lives and the peripartum period in caged housing systems. Although this type of management is intended to reduce neonatal mortality in piglets, several studies consider that there has been no significant reduction in its incidence over the last 30 years. On the contrary, cage housing has promoted the appearance of alterations during the farrowing process such as dystocia, as well as in maternal behavior and health, promoting stereotypes, skin lesions and other alterations, which not only impact the sows but also their progeny during the lactational period. Therefore, the aim of the present review is to compare the productive performance and welfare of sows and their piglets within the farrowing, lactation, and post-weaning period in both traditional and free-farrowing systems, highlighting the differences in these indicators in each of them.

Animal board invited review: The need to consider emissions, economics and pig welfare in the transition from farrowing crates to pens with loose lactating sows

In the development and implementation of housing systems for pigs, there has been a significant focus on pig welfare including loose housing of lactating sows either indoors or outdoors. However, it is equally important to consider the environmental and economic aspects of housing systems to ensure sustainability in livestock production. The aim of this work was to review the sustainability (societal and animal welfare, environmental and economic impact) of different approaches for housing farrowing and lactating sows in indoor environments. The review illustrates that like outdoor systems, indoor housing systems are challenged in meeting the three pillars of sustainability when changing the housing of lactating sows from conventional crates with permanent confinement to systems with temporary or zero-confinement. Increased space allowance increases sow welfare, but in addition, pen designs with increased space increase ammonia emission, investment and running costs. Furthermore, indoor loose lactation systems come with an increased risk for piglet mortality, which unless effectively managed, reduces animal welfare and the economic sustainability of the system. If farms retrofit existing buildings, the larger space per loose farrowing pen leads to a reduction in pen numbers and therefore herd size, reducing the farm profitability. If farmers choose to reduce herd size to meet requirements, welfare will be reduced while emissions will be increased as more sows are brought into production again in other countries, often in conventional systems with fully slatted flooring, to meet the demand for animal protein to feed the growing global population. The review indicates there are ways to house lactating sows loose indoors with increased opportunity to perform highly motivated species-specific behaviours compared to the conventional crates with continuous confinement. These systems can offer a lower risk for environmental impact and economic risk through reducing piglet mortality. Nevertheless, a trade-off for continual freedom of sow movement may be required as zero-confinement increases the risk of piglet mortality and increased emissions. It is important to raise awareness among citizens and policy makers that loose farrowing and lactating systems if applied today, come with a higher production cost and the risk of increased environmental impact. More research and development is needed in relation to the environmental and economic impact of these systems in order to give farmers the best information to invest in new and more sustainable production systems.

Defining the pig microglial transcriptome reveals its core signature, regional heterogeneity, and similarity with human and rodent microglia

Microglia play key roles in brain homeostasis as well as responses to neurodegeneration and neuroinflammatory processes caused by physical disease and psychosocial stress. The pig is a physiologically relevant model species for studying human neurological disorders, many of which are associated with microglial dysfunction. Furthermore, pigs are an important agricultural species, and there is a need to understand how microglial function affects their welfare. As a basis for improved understanding to enhance biomedical and agricultural research, we sought to characterize pig microglial identity at genome-wide scale and conduct inter-species comparisons. We isolated pig hippocampal tissue and microglia from frontal cortex, hippocampus, and cerebellum, as well as alveolar macrophages from the lungs and conducted RNA-sequencing (RNAseq). By comparing the transcriptomic profiles between microglia, macrophages, and hippocampal tissue, we derived a set of 239 highly enriched genes defining the porcine core microglial signature. We found brain regional heterogeneity based on 150 genes showing significant (adjusted p < 0.01) regional variations and that cerebellar microglia were most distinct. We compared normalized gene expression for microglia from human, mice and pigs using microglia signature gene lists derived from each species and demonstrated that a core microglial marker gene signature is conserved across species, but that species-specific expression subsets also exist. Our data provide a valuable resource defining the pig microglial transcriptome signature that validates and highlights pigs as a useful large animal species bridging between rodents and humans in which to study the role of microglia during homeostasis and disease.

Pen Versus Crate: A Comparative Study on the Effects of Different Farrowing Systems on Farrowing Performance, Colostrum Yield and Piglet Preweaning Mortality in Sows under Tropical Conditions

The present study was performed to determine the farrowing performance of sows, newborn piglet characteristics, colostrum yield, milk yield and piglet preweaning mortality in a free-farrowing pen compared to a conventional farrowing crate system in a tropical environment. A total of 92 sows and 1344 piglets were included in the study. The sows were allocated by parity into two farrowing systems, either a free-farrowing pen (n = 54 sows and 805 piglets) or a crate (n = 38 sows and 539 piglets). Backfat thickness and loin muscle depth of sows at 109.0 ± 3.0 days of gestation were measured. Reproductive performance data including total number of piglets born (TB), number of piglets born alive (BA), percentage of stillborn piglets (SB) and percentage of mummified foetuses (MF) per litter, farrowing duration, piglet expulsion interval, time from onset of farrowing to the last placental expulsion, piglet preweaning mortality rate, percentage of piglets crushed by sows and number of piglets at weaning were analysed. In addition, piglet colostrum intake, colostrum yield, Brix index and milk yield of sows were evaluated. On average, TB, BA, farrowing duration, colostrum yield and milk yield during 3 to 10 and 10 to 17 days of lactation were 14.7 ± 2.8, 12.8 ± 3.1, 213.2 ± 142.2 min, 5.3 ± 1.4 kg, 8.6 ± 1.5 kg, and 10.4 ± 2.2 kg, respectively. Sows kept in the free-farrowing pen tended to produce more colostrum than crated sows (5.5 ± 0.2 vs. 4.9 ± 0.2 kg, p = 0.080). Piglets born in the free-farrowing pen had a higher colostrum intake than those in the crate system (437.0 ± 6.9 and 411.7 ± 8.3 g, p = 0.019). However, the piglet preweaning mortality rate (26.8 ± 2.9 vs. 17.0 ± 3.8, p = 0.045) and the proportion of piglets crushed by sows (13.1 ± 2.1 vs. 5.8 ± 2.7, p = 0.037) in the free-farrowing pen were higher than those in the crate system. Interestingly, in the free-farrowing pen, piglet preweaning mortality rate in sows with high backfat thickness was higher than that in sows with moderate (37.8 ± 5.1% vs. 21.6 ± 3.6%, p = 0.011) and low (21.0 ± 6.2%, p = 0.038) backfat thickness. Moreover, the incidence of crushing in sows with high backfat thickness was higher in the free-farrowing pen than in the crate system (17.6 ± 3.6 vs. 4.0 ± 5.7, p = 0.049), but this difference was not detected for sows with moderate and low backfat thickness (p > 0.05). Milk yield of sows during 3 to 10 days (8.6 ± 0.2 vs. 8.6 ± 2.3, p > 0.05) and 10 to 17 days (10.2 ± 0.3 vs. 10.4 ± 0.4, p > 0.05) did not differ between the two farrowing systems. In conclusion, piglets born in the free-farrowing pen had a higher colostrum intake than those in the crate system. However, the piglet preweaning mortality rate and the proportion of piglets crushed by sows in the free-farrowing pen were higher than in the crate system. Interestingly, a high proportion of piglet preweaning mortality in the free-farrowing system was detected only in sows with high backfat thickness before farrowing but not in those with low and moderate backfat thickness. Therefore, additional management in sows with high backfat thickness (>24 mm) before farrowing should be considered to avoid the crushing of piglets by sows.

Transitioning from crates to free farrowing: A roadmap to navigate key decisions

There are animal welfare concerns about the continued use of permanent crating systems for farrowing and lactating sows, which is the most prevalent maternity system in global pig production. Greater societal attention in recent years has culminated in changes (or proposed changes) to regulations as well as market-driven initiatives to move away from crated systems. Transitioning from farrowing crates to systems that allow the sow greater freedom of movement and behavioral expression requires a number of key decisions, with various trade-offs apparent when trying to balance the needs of different stakeholders. This review discusses these decisions based on common questions asked by farmers, policy makers and other stakeholders when deciding on a new system to build/approve. Based on the latest scientific evidence and practical insight, decisions such as: whether to retrofit an existing barn or build a new one, what spatial dimensions are necessary per sow place, whether to adopt free farrowing or temporary crating, how to provide substrate/enrichment and be hygienic and environmentally friendly, and how to optimize the human inputs and transition between systems are considered. The aim of this paper is to provide a roadmap for those interested in uptake of higher welfare systems and practices, as well as to highlight areas requiring further optimization and research.

Freedom to Move: Free Lactation Pens Improve Sow Welfare

Farrowing crates present a major animal welfare problem. This study investigated the effects of temporary confinement at farrowing on sow welfare and aimed to determine whether this type of system could improve sow welfare through increased freedom of movement. Sows were housed in one of two farrowing accommodation treatments: conventional farrowing crates (Control) or free lactation pens (Free). Sows in the Control treatment were confined from entry to weaning, a period of five weeks. Sows in the Free treatment were temporarily confined from before farrowing (approximately 24 h) until day 4 post-partum, after which time the crate was opened, and they had increased freedom of movement. Sow physical measures (weight, back-fat thickness, hoof score, locomotion score and tear stain score) were measured at entry to farrowing accommodation and at weaning. Salivary cortisol concentration was measured throughout lactation. Farrowing duration and sow posture (Days 1, 3, 7 and 34 after entry) were recorded. Between entry and weaning, locomotion scores significantly increased for sows housed in the Control treatment compared with those housed in Free lactation pens (p < 0.01). Sows in the Free treatment were observed to use all orientations in the pen, showing that when more space is made available to them, they will choose to utilise the space. Tear staining under the left eye was found to be less in Free sows at weaning (p = 0.05), indicating reduced stress. However, salivary cortisol concentration was higher in Free sows overall; cortisol is affected by both positive and negative stimuli, and so, this may be due to factors other than stress, such as higher levels of activity and mental stimulation. These results suggest that free lactation pens can benefit sow welfare; increased freedom of movement throughout lactation can improve sow locomotory health, and as suggested by improved tear stain scores, sow stress levels may be reduced in this type of system compared with conventional farrowing crates.

Effect of alternative farrowing pens with temporary crating on the performance of lactating sows and their litters

This study was performed to development the alternative farrowing pen (AFP) and to investigate performance and behavior of lactating sows and their litter. A total of 64 multiparous sows were randomly divided into two groups and were allocated to farrowing crates (FCs) and AFPs. The AFPs contained a crate and support bars that could be folded to provide the sows with extra space on day 5 postpartum. Behavior was recorded by charge-coupled device cameras and digital video recorders, and the data were scanned every 2 min to obtain an instantaneous behavioral sample. Farrowing systems did not affect feed intake, back-fat thickness, litter size and piglet weight at birth and weaning (p > 0.05). In addition, there were no differences in the number of crushed piglets between the two farrowing systems (p > 0.05). However, the weaning-to-estrus interval was shorter in the sows of the AFPs than in thous of the FCs (p < 0.05). The sows spent most of their time lying down during the lactating period, at about 80% lateral recumbency and 10%–15% ventral recumbency. The only significant differences were in the feeding and drinking behavior between sows in the two farrowing systems (p < 0.05). The FC sows displayed more feeding and drinking behavior than the AFP sows, especially in the late lactating period (p < 0.05). Piglets in the FCs tended to spend more time walking than piglets in the AFPs (p < 0.05), whereas there were no differences in suckling and lying behavior between piglets in the two farrowing systems (p > 0.05). It is concluded that the AFPs with temporary crating until day 4 postpartum did not negatively affect performance and crushed piglet compared with the FCs. It also may improve animal welfare by allowing sows to move and turn around during the lactating period. Further research is needed to find suitable housing designs to enhance productivity and animal welfare.

Review of Temporary Crating of Farrowing and Lactating Sows

Temporary crating (TC) provides lactating sows with the opportunity to move more freely after crate opening a few days after parturition. The aim of this paper was to evaluate whether TC gives overall welfare improvement when compared to permanent crating or free farrowing. This review shows that when pens with TC allow the sows to turn during the majority of time in the farrowing unit, it is the pen design and period of confinement in a crate within it that influence the extent to which different functional and motivated behaviors can be fulfilled. This review also indicates that there are at least short-term benefits to sows when confinement is reduced, as shown by reported increases in motivated behaviors such as exploration and interactions with piglets when not permanently crated. It remains unclear whether there are any longer-term beneficial effects (until or beyond weaning) due to the paucity of studies. Furthermore, it is uncertain whether the observed short-term benefits translate to other welfare indicators. Research findings indicate no reduction in the frequency of stereotypies or body lesions and do not provide a clear answer regarding sow stress response when released from confinement. Compared to free farrowing, TC appears beneficial for reducing piglet mortality. The impact of the time of onset of TC on the farrowing process and piglet mortality have been inconsistent. While confinement before farrowing prevents nest building behavior, consequences of this for sow physiology have been ambiguous. Confining the sow briefly after farrowing may be the best compromise, allowing the sow to perform motivated nest-building behavior, but the risks of crushing during the unconfined farrowing period may increase. Subsequent crate reopening seems to increase piglet mortality but only if done earlier than 3–5 days after farrowing. The review also provides methodological considerations, a proposal for consistent and accurate terminology when describing systems and highlights gaps of knowledge. In conclusion, TC is a step forward to better pig welfare compared to the farrowing crate, as it allows some freedom of movement for sows without impairing piglet welfare. However, more comprehensive research is needed to draw sound conclusions as to whether TC is a viable transition from permanent crating to free farrowing.

Short confinement of sows after farrowing, but not pen type affects live-born piglet mortality

Over the last decades, permanent crating of farrowing and lactating sows has led to serious public concerns with regard to sow welfare. As one alternative, it has been suggested to restrict crating to the period when suckling piglets are at the highest risk to die. Therefore, the aim of this study was to investigate live-born piglet mortality with regard to different confinement periods (CFP) as well as farrowing pen types. On three research farms (A, B and C), four confinement periods were compared: In CFP 0 (control), sows were not confined at all, sows in CFP 3 were crated after the end of farrowing for three days. In CFP 4, sows were confined one day before the due date of farrowing until three days after parturition and sows in CFP 6 were crated one day before expected farrowing until five days after parturition. Furthermore, five different pen types designed for temporary crating (PT; 5.5-7.3 m²) were compared. In total, production data from 638 litters were analysed. For each piglet found dead (n = 1 580), the cause of death was determined by the farm personnel and verified by necropsy (all three farms) and additional video analysis (farms A and B only). Data were analysed using logistic mixed models with CFP 0 and pen type Fluegel as reference categories (CFP 0 was control and this pen type was present on all three farms and the largest number of litters was born in this pen type). Live-born piglet mortality was lower in temporarily crated sows than in sows without confinement (CFP 0; P < 0.015). Pairwise posthoc tests did not reveal differences between CFP 3, CFP 4 and CFP 6 (odds ratios 0.75, 0.59 and 0.69), nor between pen types. Additional factors associated with increasing live-born piglet mortality were larger litter size, higher sow parity as well as the administration of hormones around farrowing. Factors influencing mortality due to crushing were similar to those for total live-born mortality with the exception of CFP 3 not differing significantly from CFP 0. It can be concluded, that confinement of the sow for three days after farrowing is an effective measure to reduce live-born piglet mortality in the pen types tested. An extension of the confinement period to five days after parturition does not result in a further reduction of live-born mortality rate.

How Housing Conditions Determine the Welfare of Pigs

Humans who care for pigs prefer an environment that not only allows the pigs to express their natural behaviors but also limits the development of aggression and stereotypes. Most of the behavioral and health problems encountered by pigs in barren, conventional conditions are solved by alternative housing systems. However, it is not known whether these systems are advantageous in terms of the performance of pigs. In this work, we review the effects of housing systems on pigs' behaviors and performance, which are among the major indicators of the welfare of these animals. Research results point out that outdoor systems are more ideal for sows and fatteners than buildings. Nonetheless, outdoor housing is associated with two major effects in both groups: increased activity due to environmental exploration and higher space allowance, and increased incidence of injuries compared to indoor systems. Sows are more active when housed in groups, but they experience an increased frequency of injuries. According to the literature, group-housed sows give birth to healthy piglets with good daily weight gains. The difference in the fattening and slaughter performance of pigs raised indoors vs. outdoors remains unclear, and the results reported so far are inconsistent. Outdoor systems seem to be associated with a higher incidence of osteochondrosis and lesions of elbow and hock joints, whereas indoor systems cause a greater degree of body soiling in pigs. Based on the reviewed literature, it may be concluded that outdoor housing helps to solve behavioral issues in pigs but leads to other problems in pig production.

Behavioral Observation Procedures and Tests to Characterize the Suitability of Sows for Loose-Housed Farrowing Systems

Simple Summary

In this study, different behavior tests were developed and applied to characterize the behavior of sows against humans and piglets in systems with short-term fixation only. In loose-housed sows, it is of extreme importance that the sows neither attack the stockpersons nor crush their piglets through carelessness. Selecting the sows for the respective traits might show positive effects in a successful realization of these husbandry systems. For example, the Dummy Arm Test simulated catching the piglets. In the Towel Test, the general reaction to unknown stress situations was tested by throwing a towel towards the sow during a resting phase. Another test simulated the emptying of the trough to simulate interaction with humans during a routine procedure. The study showed that the majority of the sows reacted calmly. Nesting and lying behavior were also analyzed, as was the behavior of sows when their litters returned after a short separation. This study showed that the behavioral observation procedures and designed tests are suitable to characterize sows’ behavior towards humans and piglets with regard to traits that are particularly important in systems without fixation.

Abstract

The objective of the study was to evaluate behavioral observation procedures and tests to characterize sows’ behavior for their suitability for free farrowing systems. Nest building activity (NB), lying-down behavior (LDB), and position after lying down (PLD) were assessed. Four tests were designed to characterize the reaction of sows to a novel object and an unexpected situation (Towel Test, TT), behavior towards humans (Dummy Arm Test, DAT; Trough Cleaning Test, TCT), and behavior towards piglets (Reunion Test, RT). The study was performed on a nucleus farm in 37 batches including 771 purebred landrace sows housed in farrowing pens with short-term fixation. The assessment of NB started 2 days before the expected date of the farrowing. In 56.2% of the observations, the sows showed increased chewing activity on gunnysacks. The LDB and PLD were assessed on days 3 and 19 post partum (p.p.). In 49.1% of the observations, sows showed careful lying-down behavior. In 50.1% of cases, sows preferred the stomach-teats-position when lying down. With the DAT on day 4 p.p., in 89.3% of observations, no or only slight reactions of the sow were documented. The TT and TCT were performed on days 3 and 10 p.p. Strong defensive reactions of animals towards humans were recorded in 4.5% of the observations in the TT, and in 4.0% of the observations in the TCT. In the RT on day 3 p.p., in 61.8%, a joyful response of the sows to the reunion with their piglets was observed. This study showed that the behavioral observation procedures and designed tests are suitable to characterize sows’ behavior towards humans and piglets with regard to traits that are particularly important in systems without fixation.

Early socialisation in group lactation system reduces post-weaning aggression in piglets

BACKGROUND

Pre-weaning group housing for sows and their litters is expected to enhance animal welfare. However, knowledge of potential benefits of pre-weaning socialisation for piglets after weaning is still lacking.

METHODS

Weaner pigs were mixed in groups of 10, using littermates (LM) from pre-weaning group housing (Gr) and from farrowing pens with crates (Co). Groups were formed as follows: Gr/Gr (5 LM from Gr + 5 LM from Gr), Gr/Co (5 LM from Gr + 5 LM from Co), Co/Co (5 LM from Co + 5 LM from Co).

RESULTS

During 24 h after mixing, piglets in Co/Co fought more than in Gr/Co and Gr/Gr. Piglets in Co/Co had more unclear fighting results than in Gr/Co and Gr/Gr. Four days after mixing, piglets in Co/Co were more injured than in Gr/Co and Gr/Gr.

CONCLUSION

Early socialised piglets may have better social skills when meeting familiar and unfamiliar conspecifics after weaning.

Positive Human Contact and Housing Systems Impact the Responses of Piglets to Various Stressors

Simple Summary

Early life experiences such as contact with humans, maternal care and the physical environment can play a substantial role in shaping behavioural and physiological responses to stress. This experiment studied the effects of lactation housing systems and human interaction on stress in young pigs. We hypothesised that piglets handled in a positive manner and reared in loose farrowing and lactation pens with increased opportunity for interaction with their dam, greater space and more complexity in their physical environment have improved stress resilience than piglets reared in traditional farrowing crates with routine contact from stockpeople. In both housing systems, providing regular opportunities for positive human interaction reduced piglets’ fear of humans and routine husbandry procedures imposed by humans, and reduced the number of injuries obtained after weaning. However, contrary to the expected findings, piglets from loose farrowing and lactation pens were more reactive to capture by a stockperson, more fearful of novel and human stimuli, had more injuries during the lactation period and were more likely to perform behaviours which may be indicative of reduced coping after weaning. Whether these effects are specific to the loose farrowing and lactation system studied in this experiment or are reflective of other loose systems requires further research.

Abstract

This experiment studied the effects of lactation housing systems and human interaction on piglets’ responses to routine stressors. Forty litters of piglets were reared in either a standard farrowing crate (FC) or a loose farrowing and lactation pen (LP; PigSAFE pen) and received either routine contact with humans (C) or regular opportunities for positive human contact (+HC; 3 min of patting, stroking and scratching 5 times/week). Behavioural and physiological responses to routine husbandry procedures, weaning, novelty and humans were studied in addition to effects on piglet growth, injuries and survival. Compared to C piglets, +HC piglets vocalised for shorter durations (p = 0.018) during husbandry procedures and showed a lower intensity of escape behaviour during iron injection (p = 0.042) and oral vaccination (p = 0.026) at 3 d of age, capture at 2 wk of age (p < 0.001), and intramuscular vaccination (p = 0.005) at 3 wk of age. +HC piglets at 2 wk of age were faster than C piglets to approach (p = 0.048) and interact (p = 0.042) with a stationary unfamiliar human. Compared to LP piglets, FC piglets showed a lower intensity of escape behaviour during capture and iron administration by a stockperson at 3 d of age (p = 0.043). FC piglets at 2 wk of age were faster than LP piglets to approach (p = 0.005) and interact (p = 0.027) with a novel object and approach (p = 0.009) and interact (p = 0.008) with an unfamiliar human. FC piglets had fewer injuries than LP piglets at 2 wk of age (p = 0.004). +HC pigs had fewer injuries than C pigs after weaning (p = 0.003). After weaning there were more pigs from LP than FC observed to be upright (both stationary, p = 0.002 and walking, p = 0.024), vocalizing (p = 0.004), nosing another pig (p = 0.035) and nosing the pen floor (p = 0.038). There were no significant effects on neutrophil:lymphocyte ratios or plasma cortisol concentrations 1.5 h after weaning. However, 25 h after weaning +HC pigs had higher haptoglobin concentrations than C pigs (p = 0.002), and C/LP pigs had higher cortisol concentrations than +HC/LP and C/FC pigs (p = 0.012). There were no significant effects on piglet growth, the number of piglets born alive or the number stillborn, however there were more piglets weaned from FC than LP (p = 0.035). The results from this experiment raise questions that require further research on the ability of pigs reared in loose pens to cope with stressors such as exposure to humans, novelty, husbandry procedures and weaning. This experiment also provides evidence that regular positive human interaction reduces pigs’ fear of humans and husbandry procedures imposed by stockpeople. More research is required to determine if any of these effects are sustained long-term.

Behavioral activities of white-lipped peccary (Tayassu pecari, Link, 1795) in a semi-intensive farming system in Brazil

ABSTRACT This study aimed to describe the main behaviors of white-lipped peccaries (Tayassu pecari) expressed in a semi-intensive production system in Brazil. The behavioral activities of two groups of peccaries allocated in two paddocks were assessed, totaling 17 adult animals and eventual pups in different developmental stages. The animals were visually observed using the ad libitum sampling and scan sample methods during the adaptation and experimental phases, respectively. The animals were evaluated in the morning, afternoon, and at night. The behavioral activities observed by ad libitum sampling comprised feeding, pool contact, moving, staying inside the handling area, resting, mud bathing, mutual rubbing, rubbing, aggression, sexual behavior, copulation, foraging, breastfeeding, sleeping, territorial marking, interactions, birthing, gnawing, and other behaviors. All behaviors observed by the ad libitum sampling method were confirmed in the experimental period by scan sample, except for territorial marking and birthing. The effects of time of day were statistically significant (p <0.05) for eating, pool contact, movement, staying inside the handling area, resting, mud bathing and sleeping. These results contribute to the understanding of instinctive animal habits and to the development of nutritional, environmental and health management protocols that meet the requirements of peccaries.

Effects of Farrowing Stall Layout and Number of Heat Lamps on Sow and Piglet Production Performance

Simple Summary

In the commercial swine industry, farrowing stalls are commonly used as a strategy to reduce piglet pre-weaning mortalities caused by sow over-lay. Farrowing stall dimensions have generally remained the same over the past 50 years in the United States, even though the sizes of both the sows and litters have increased considerably. This extensive field study investigated if sow and piglet productivity would be affected when housed in stalls of traditional layout, additional area for the piglets, or additional area for the sow. All three layouts were also tested with use of one or two supplementary heat lamps in the creep area. Results show that stall layout and number of heat lamps had no statistical impact on production outcomes. However, seasonal differences, sow parity, and number of litter mates did have significant effects. Providing larger stalls or an additional heat lamp costs more for the producer but did not yield production improvements.

Abstract

Most farrowing facilities in the United States use stalls and heat lamps to improve sow and piglet productivity. This study investigated these factors by comparing production outcomes for three different farrowing stall layouts (traditional, expanded creep area, expanded sow area) and use of one or two heat lamps. Data were collected on 427 sows and their litters over one year. Results showed no statistical differences due to experimental treatment for any of the production metrics recorded, excluding percent stillborn. Parity one sows had fewer piglets born alive (p < 0.001), lower percent mortality (p = 0.001) and over-lay (p = 0.003), and a greater number of piglets weaned (p < 0.001) with lower average daily weight gain (ADG) (p < 0.001) and more uniform litters (p = 0.001) as compared to higher parity sows. Farrowing turn, associated with group/seasonal changes, had a significant impact on most of the production metrics measured. Number of piglets born influenced the percent stillborn (p < 0.001). Adjusted litter size had a significant impact on percent mortality (p < 0.001), percent over-lay (p < 0.001), and number of piglets weaned (p < 0.001). As the number of piglets weaned per litter increased, both piglet ADG and litter uniformity decreased (p < 0.001). This information can be used to guide producers in farrowing facility design.

Caffeine supplementation at birth, but not 8 to 12 h post-birth, increased 24 h pre-weaning mortality in piglets

Pre-weaning mortality represents a major economic loss and welfare concern for the global pork industry. Caffeine administration prior to, or after, parturition positively affects metabolic parameters associated with survival in newborn animals. However, its effects on piglet viability and survival when administered within the first 24 h of life have not been evaluated. This study determined the effect of caffeine treatment during the 24 h postpartum period on piglet viability, growth and survival. Piglets received 30 or 0 mg of caffeine orally at birth or 8 to 12 h following birth and again at 24 h. Vitality, meconium staining and blood lactate were assessed at birth. Time to first reach the udder and suckle was recorded. Body weight and rectal temperature were measured at 10 min, 24 and 72 h after birth. A blood sample for analysis of serum immunoglobulin G was collected at 24 h, and BW and survival were monitored to 20 days of age. Caffeine had no effect on body temperature, blood glucose, serum immunoglobulin G concentration or weight (P > 0.05). However, when caffeine was administered at birth, it significantly increased 24 h mortality in piglets (P < 0.05). Piglet mortality between birth and weaning also tended to be higher for piglets receiving caffeine at birth (P = 0.063). These data demonstrate that caffeine administration to piglets at birth, but not 8 to 12 h after birth, impaired piglet survival. Further research into caffeine dosage and timing postpartum is required to establish its efficacy.

Comparison of three different farrowing systems: skin lesions and behaviour of sows with special regard to nursing behaviour in a group housing system for lactating sows

While group housing (GH) is mandatory in the European Union for the greater part of pregnancy, single housing in farrowing crates (FCs) during lactation that restrict sows in most of their natural behaviour patterns is still practised on a large scale. Research is urgently needed to develop alternative farrowing systems that improve sows' welfare. Therefore, sows in three different farrowing systems - pens with FC, loose housing (LH) pens and GH for six sows - were compared regarding the level of skin injuries and their active and resting behaviour. A skin injury score was assessed for 15 body parts of 102 sows in six batches on 3 days (days 1, 14 and 34). In total, the active and resting behaviour of 77 sows in six batches was examined on 3 days (days 18, 25 and 32) between 0700 h and 1900 h by means of a scan sampling method. The suckling behaviour and the level of cross-suckling were analysed in GH by means of direct observation in four batches during three 4-h sampling periods (days 17, 24 and 31). No significant differences were found in total skin injuries when the sows entered the systems (day 1), but GH sows showed significantly higher total skin injuries compared to FC and LH sows in the middle (day 14) and at the end (day 34) of the lactation period. A significant difference between FC and LH sows was never seen. Differences were found for the proportion of different body postures between the three systems. The odds for lying in lateral recumbency versus standing and sitting versus standing were significantly higher for FC and LH sows compared to GH sows. Additionally, sows were significantly more likely to be standing as opposed to lying in lateral recumbency as the lactation period progressed. Cross-suckling was a frequent behaviour in GH, seen in 35.0% of all successful suckling bouts. However, only an average of 0.56 piglets per successful suckling bout was observed cross-suckling, suggesting only a few piglets were engaged in cross-suckling. In conclusion, the skin injury score was only moderately increased in GH compared to FC and LH and comparable to pregnant group-housed sows, both free farrowing systems seemed to be an environmental enrichment for lactating sows and good management cannot prevent the occurrence of cross-suckling in a GH system, but can probably reduce it.

Microbiological air quality in free-farrowing housing systems for sows

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Farrowing systems without confinement do not impair microbiological air quality.

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Single loose-housing system proved to be hygienically advantageous.

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Ventilation and hygiene routines can be kept when changing to free-farrowing systems.

This study investigates air hygienic characteristics of housing systems without fixation for lactating sows, with a focus on microbiological air quality. For animal welfare considerations, free-farrowing systems have been developed to replace those with farrowing crates (FC) and are currently available on the market. A group housing system (GH) for six lactating sows, a single loose-housing system (LH), and a conventional system with FC were tested. By maintaining similar management conditions, microbiological air quality was examined in eight batches with 148 farrowings in total with samplings at the beginning, in the middle, and at the end of the occupancy period of 33 days. No significant differences between the systems were observed in the concentration of total airborne bacteria (TAB), haemolytic streptococci (HS), molds, or yeasts. However, the concentrations of TAB and HS increased significantly over time. Additionally, significant correlations were detected for LH and FC between TAB and HS, and between TAB and carbon dioxide; significant correlations between TAB and inside temperature and total animal weight were revealed only in GH. Significant correlations between TAB and both the dust and inside humidity parameters were found only in FC. Given these results, it was shown that the free-farrowing systems used here do not necessarily lead to poorer microbiological air quality.

The Effect of Sows' and Piglets' Behaviour on Piglet Crushing Patterns in Two Different Farrowing Pen Systems

Simple Summary

Farrowing crates—narrow cages where sows are kept during lactation—impede the sow in the expression of natural behaviours and, therefore, cause animal welfare concerns. However, piglet losses due to crushing by the sow are effectively reduced by farrowing crates. Hence, there is an urgent need to find a practical compromise between sows’ and piglets’ welfare. The aim of this study was to test two farrowing pens without fixation of the sow in comparison to pens with a farrowing crate. Piglet mortality, piglet crushing and sow and piglet behaviour in the first 72 h after birth were analysed. Piglet mortality was higher due to increased levels of piglet crushing in the free-farrowing pens. However, the majority of crushing occurred in the first three days after birth. The recorded active and resting behaviour of sows in the first 72 h after birth hardly highlighted differences between the three systems, i.e., sows in free-farrowing pens hardly used the offered possibilities for activity in the first 72 h after birth. In conclusion, our results suggest that a temporary fixation for a few days after birth could be sufficient to significantly reduce piglet crushing and could represent a practical solution for future farrowing systems.

Abstract

Pens with farrowing crate (FC) and two differently designed free-farrowing pens (LH-pens: 7.3 m², plastic flooring; GH-pens: 5 m², cast-iron and concrete flooring) were compared regarding piglet losses and postpartum sow behaviour (all treatments) and reasons for piglet crushing and postpartum litter behaviour (LH and GH). One-hundred-and-three crushing events were analysed in eight batches concerning sows’ posture changes that crushed piglets and age of crushed piglets. Posture change frequency, amounts of single posture changes and total time spent in different body postures were evaluated for 41 sows (14 FC-sows, 13 LH-sows and 14 GH-sows) in six batches. Litter behaviour (location, active/inactive scoring, resting behaviour next to the sow) was analysed during sows’ posture changes and piglet crushing. Piglet mortality was higher in LH (25.6%) and GH (19.9%) compared to FC (12.3%) due to higher levels of piglet crushing. Most crushing occurred during the three days postpartum in LH (92.7%) and GH (83.9%). However, crushing patterns differed between LH (rolling: 68.2%; sit-to-lie: 18.2%; stand-to-lie: 11.4%) and GH (rolling: 38.2%; sit-to-lie: 30.9%; stand-to-lie: 16.4%) and varying piglet behaviour may be the cause for this. The postpartum period was characterized by inactivity of the sow and behavioural differences were rarely seen between systems.

Sow stress levels and behavior and piglet performances in farrowing crates and farrowing pens with temporary crating

Farrowing pens with temporary crating have been developed as a compromise between conventional farrowing crates and pens to better accommodate the welfare of both sow and piglets during lactation. However, not much is known about the behavioral and physiological consequences of early removal of confinement on the sow and piglets during lactation. The aim of this study was to assess the effects on sow and piglet performance of temporary crating until 3-d postpartum at 2 times points, immediately after confinement removal and 25 d into lactation. Sows were crated from 5-d prepartum either to weaning (permanently crated-PC group; N =14) or to D3 (83.0 ± 1.3 h) postpartum (Temporarily crated - TC group N = 13). Sow postural changes, activity, cortisol and IgA concentrations, and piglet body weight gain and behavior were assessed on D4 and on D25 postpartum, whereas piglet mortality was assessed throughout lactation. Data were analyzed using PROC GLM and PROC GENMOD of SAS. On D4 postfarrowing, TC sows were more active (10.9% vs. 7.1%; SEM: 0.8; P = 0.002), rolled more frequently (21.3% vs. 14.4%; SEM: 1.6; P = 0.008), and had lower IgA concentrations (139.7 vs. 75.2 µg/mL; SEM: 20.3; P = 0.040) than PC sows. No effects of housing were found (P > 0.05) on standing-to-lying movement or cortisol concentrations. No differences for any variables were found (P > 0.05) on D25. Mortality, body weights, and activity levels at the udder or in the pen of pigs born to PC sows did not differ (P > 0.05) from those of piglets born to TC sows on D4 nor on D25. This study indicates that removal of confinement on the 4th-d postpartum may have had small short-term positive effects on sow behavior and stress levels (as measured by IgA), and that it did not impair piglets' behavior and performance during lactation. Therefore, this work suggests that temporary crating limited to the first 3-d postpartum might be a feasible alternative to improve welfare under intensive production conditions.

How does intrauterine crowding affect locomotor performance in newborn pigs? A study of force generating capacity and muscle composition of the hind limb

Intrauterine crowding (IUC) considerably influences postnatal traits in a polytocous species such as the pig. Previously, our group described how IUC affects locomotion during the piglet’s first days of life (until 96 h after birth). We noted a reduced motor performance in piglets with a low birth weight and low vitality (L piglets), compared to piglets with a normal birth weight and normal vitality (N piglets), indicating L piglets are unable to produce enough force. Our current study investigates whether this observed force deficit in L piglets is caused by a reduced force generating capacity in the muscles and/or a lower percentage of type II (fast-contracting) fibers. Volume and fiber length of the main extensor muscles of the hind limb were used to estimate the physiological cross-sectional area (PSCA) and hence calculate the maximal isometric force generating capacity (F_iso-max) of the hind limb. To check for developmental differences between the muscles of L and N piglets, F_iso-max was normalized to body weight (BW), thus yielding a dimensionless variable F’_iso-max. To check for differences in muscle composition, m. vastus lateralis was stained immunohistochemically in order to determine the percentage of type II fibers through image analysis. Our results indicate that L piglets have a reduced absolute force generating capacity due to a lesser muscle mass, compared to N piglets. However, when normalized to BW L piglets actually show a larger force generating capacity, suggesting their muscles are more voluminous, given their body mass, than those of N piglets. However, no differences between L and N piglets were detected with regard to muscle composition of the m. vastus lateralis. Based on our data, we can say that neither normalized force generating capacity, nor muscle composition (of the m. vastus lateralis) can explain the observed force deficit in L piglets and as such the effect of IUC on locomotor performance.

Factors affecting piglet mortality during the first 24 h after the onset of parturition in large litters: effects of farrowing housing on behaviour of postpartum sows

The present study aimed to identify the factors that affect immediate (within 24 h after farrowing onset) postnatal piglet mortality in litters with hyperprolific sows, and investigate their associations with behaviour of postpartum sows in two different farrowing housing systems. A total of 30 sows were housed in: (1) CRATE (n=15): the farrowing crate closed (0.80×2.20 m) within a pen (2.50×1.70 m), and (2) OPEN (n=15): the farrowing crate open (0.80×2.20×1.80 m) within a pen (2.50×2.40 m) with a provision of 20 ls of hay in a rack. A total of 518 live born piglets, produced from the 30 sows, were used for data analyses during the first 24 h after the onset of parturition (T24). Behavioural observations of the sows were assessed via video analyses during T24. Total and crushed piglet mortality rates were higher in OPEN compared with CRATE (P&lt;0.01, for both). During T24, the OPEN sows tended to show higher frequency of postural changes (P=0.07) and duration of standing (P=0.10), and showed higher frequencies of bar-biting (P&lt;0.05) and piglet trapping (P&lt;0.01), when compared with the CRATE sows. During T24, the mortality rates caused by crushing were correlated with the piglet trapping event (r=0.93, P&lt;0.0001), postural changes (r=0.37, P&lt;0.01), duration of standing (r=0.32, P&lt;0.01) and frequency of bar-biting behaviour (r=0.51, P&lt;0.01) of the sows (n=30). In conclusion, immediate postnatal piglet mortality, mainly due to crushing, may be associated with potential increases in frequency of postural changes, duration of standing and incidence of piglet trapping in postpartum sows in the open crate system with large litters.

Towards Farm Animal Welfare and Sustainability

Simple Summary

The protection and enhancement of farm animal welfare has become an increasingly important component of livestock systems and animal-based food supply chains in many of the more economically developed countries around the world. With the growth of debates around environmental sustainability and food security at the international and global scale, this paper explores the ways in which farm animal welfare, as a public concern, as a science, and as a policy and regulatory area can articulate with these other debates in a comprehensive and holistic manner.

Abstract

As farm animal welfare becomes an increasingly important component of contemporary global livestock production, animal welfare science and animal welfare policy-making need to find new ways of entering global debates over food security and sustainability. In this paper, we explore the means by which both animal welfare science and policy should articulate with these emerging global debates. Having first established the important gains in animal welfare policy and the maturity of animal welfare science, we identify and explore the potential impact of these current debates and argue that they have the potential for profound change in our understanding of, and our response to, the welfare of animals. We conclude the paper with a number of possible recommendations for how a scientifically informed, sustainable animal welfare policy might flourish.

Temporary crate opening procedure affects immediate post-opening piglet mortality and sow behaviour

Producers are interested in utilising farrowing systems with reduced confinement to improve sow welfare. However, concerns of increased mortality may limit commercial uptake. Temporary confinement systems utilise a standard crate which is opened 3 to 7 days postpartum, providing protection for neonatal piglets at their most vulnerable age and later increased freedom of movement for sows. However, there is anecdotal evidence that piglet mortality increases immediately after the temporary crate is opened. The current study aims were to determine if piglet mortality increases post-opening, to trial different opening techniques to reduce post-opening piglet mortality and to identify how the different opening techniques influence sow behaviour. Three opening treatments were implemented across 416 sows: two involved opening crates individually within each farrowing house when each litter reached 7 days of age, in either the morning or afternoon (AM or PM), with a control of the standard method used on the farm to open all crates in each farrowing house simultaneously once the average litter age reached 7 days (ALL). Behavioural observations were performed on five sows from each treatment during the 6 h after crate opening, and during the same 6 h period on the previous and subsequent days. Across all treatments, piglet mortality was significantly higher in the post-opening than pre-opening period (P&lt;0.0005). Between opening treatments, there were significant differences in piglet mortality during the 2 days after crate opening (P&lt;0.05), whilst piglet mortality also tended to differ from crate opening until weaning (P=0.052), being highest in ALL and lowest in PM. Only sows in the PM treatment showed no increase in standing behaviour but did show an increased number of potentially dangerous posture changes after crate opening (P=0.01), which may be partly attributed to the temporal difference in observation periods. Sow behaviour only differed between AM and ALL on the day before crate opening, suggesting the AM treatment disrupted behaviour pre-opening. Sows in AM and PM treatments showed more sitting behaviour than ALL, and therefore may have been more alert. In conclusion, increases in piglet mortality after crate opening can be reduced by opening crates individually, more so in the afternoon. Sow habituation to disturbance before crate opening may have reduced post-opening piglet mortality, perhaps by reducing the difference in pre- and post-opening sow behaviour patterns.

Behaviour and performance of suckling gilts and their piglets in single housing with different fixation times

Abstract. The objective was to evaluate suckling performance and behaviour traits of gilts and piglets in two different single-housing farrowing systems under practical conditions. Performance data of 70 crossbred gilts and their 842 piglets were collected. The behavioural observation included 17 gilts and 211 piglets. Gilts of the control group (full-time crating, FTC) were fixed during farrowing and suckling (Pro Dromi® 1), and in the experimental group (short-time crating, STC) gilts were fixed for 6 days postpartum (p.p.) only (Pro Dromi® 1.5). Six farrowing crates were included in each group, and six replications were carried out. Performance data were collected and gilts' and piglets' behaviour was observed with 10 min scan samples and categorized by standing, walking (only in STC), sitting and lying (side and belly). The management and the housing systems were in accordance with the Tierschutz-Nutztierhaltungsverordnung (TierSchNutztV, 2017). No significant (p  >  0.05) differences between FTC and STC were found in piglets born alive (13.2 and 13.9, respectively), loss of piglets (1.4 and 1.55, respectively) and weaned piglets including cross-fostering (12.0 and 12.4, respectively). Piglet loss due to crushing was 0.6 (FTC) and 0.64 (STC), with no significant difference (p  >  0.05). Overall, 82.5 % of all piglets killed due to crushing were lost from farrowing to day 2 p.p. The daily gain of STC piglets was significantly higher than that of FTC piglets (205 g vs. 199 g, respectively; p  <  0.05) during the suckling period (3 weeks). Concerning gilts' behaviour, significant differences (p  ≤  0.05) were found in sitting duration only (FTC 5.8 % and STC 4.0 %, respectively). FTC piglets spent more time lying, sitting and standing (7.4 % vs. 4.4 %, 0.5 % vs. 0.4 %, 9.6 % vs. 8.4 %, respectively; p  ≤  0.05). The reason could be the higher acceptance of the piglet nest in STC. It was possible to conclude that gilts' welfare was improved by STC compared to FTC, and farrowing crates with loose single housing did not lead to higher piglet loss in the suckling period. An earlier end of the fixation period of the gilt at day 2 or 3 p.p. should be tested.

Mutilating Procedures, Management Practices, and Housing Conditions That May Affect the Welfare of Farm Animals: Implications for Welfare Research

A number of mutilating procedures, such as dehorning in cattle and goats and beak trimming in laying hens, are common in farm animal husbandry systems in an attempt to prevent or solve problems, such as injuries from horns or feather pecking. These procedures and other practices, such as early maternal separation, overcrowding, and barren housing conditions, raise concerns about animal welfare. Efforts to ensure or improve animal welfare involve adapting the animal to its environment, i.e., by selective breeding (e.g., by selecting "robust" animals) adapting the environment to the animal (e.g., by developing social housing systems in which aggressive encounters are reduced to a minimum), or both. We propose adapting the environment to the animals by improving management practices and housing conditions, and by abandoning mutilating procedures. This approach requires the active involvement of all stakeholders: veterinarians and animal scientists, the industrial farming sector, the food processing and supply chain, and consumers of animal-derived products. Although scientific evidence about the welfare effects of current practices in farming such as mutilating procedures, management practices, and housing conditions is steadily growing, the gain in knowledge needs a boost through more scientific research. Considering the huge number of animals whose welfare is affected, all possible effort must be made to improve their welfare as quickly as possible in order to ban welfare-compromising procedures and practices as soon as possible.

The behaviour and welfare of sows and piglets in farrowing crates or lactation pens

Temporary confinement during parturition and early postpartum may provide an intermediary step preceding loose housing that offers improvement in sow and piglet welfare. Three experiments were conducted to investigate the implications of replacing farrowing crates (FCs) with an alternative housing system from 3 days postpartum until weaning. In each experiment sows farrowed in FCs and were randomly allocated at day 3 of lactation to either a FC or a pen with increased floor space (lactation pen (LP)) until weaning. In experiment 1, piglet growth and sow and piglet skin injuries were recorded for 32 sows and 128 focal piglets in these litters. Behaviour around nursing and piglet behavioural time budgets were also recorded for 24 of these litters (96 focal piglets for time budgets). In experiment 2, measures of skin injury and behavioural time budgets were conducted on 28 sows and 112 focal piglets. The behavioural response of sows to piglet vocalisation (maternal responsiveness test (MRT)) was also assessed. In experiment 3, piglet mortality from day 3 of lactation until weaning was recorded in 672 litters over 12 months. While housing did not affect piglet weight gain in experiment 1, or piglet skin injuries in experiments 1 or 2, sows in both experiments sustained more injuries in LP than FC (experiment 1, 2.9 v. 1.4; experiment 2, 2.5 v. 0.8 lesions/sow; P0.05). Thus, housing sows and litters in LP from day 3 of lactation minimises piglet mortality while improving maternal behaviour in sows and social behaviour in piglets.

The influence of the thermal environment and other early life events on growth rate of piglets during lactation

The effects of early life events on average daily weight gain from birth to day 21 (ADG) of suckling pigs kept at different room temperatures (15°C, 20°C and 25°C) from birth to weaning were investigated. Data were collected from litters born by 61 sows in a loose housing system. The ADG for piglets with low birth weight (estimated for birth weights below the 10% percentile) was estimated to be 20 to 30 g higher per day at room temperature 20°C to 25°C compared with 15°C. In contrast, the ADG during the lactation period decreased for larger piglets (estimated for birth weights above the 10% percentile) by 28 g/day at room temperature 25°C compared with 15°C. Thus, high ambient temperatures (20°C to 25°C) are favourable for the growth in smaller piglets during lactation. Neither latency to first suckle nor birth-induced hypoxia, measured as concentration of umbilical cord lactate, affected the growth rate of the piglets. Lowest rectal temperature during the first 24 h after birth had a long-term negative effect on ADG (P<0.05), so that piglets with a lowest rectal temperature of 32.8°C (10% percentile) had an ADG which was on average 19 g lower per day than piglets with a rectal temperature of 37.3°C (90% percentile). Our results showed that hypothermia at birth, low birth weight and high number of suckling piglets lead to reduced ADG during the suckling period. The results suggest that keeping the room temperature at 20°C during lactation to some extent could compensate for the otherwise negative effects of low birth weight on ADG in piglets without decreasing the ADG of high birth weight piglets. However, to avoid hypothermia in the smallest piglets it may be beneficial to increase the room temperature above 20°C during the farrowing period of loose housed sows.