Multi-suckling System Research Articles

Effects of timing of grouping and split-weaning on growth performance and behaviour of piglets in a multi-suckling system

Variation in body weight (BW) of piglets at weaning is a drawback for successful implementation of multi-suckling (MS) systems. The current study investigated the combination of two intervention strategies, i.e. the timing of grouping and split-weaning, aiming to improve the BW gain of low birthweight piglets in an MS system and thereby reduce the BW variation at weaning on day 48 postpartum (p.p.). Eight batches of 5 sows with their litters were divided into 4 control (CTRL) and 4 treatment (TREAT) batches. In each litter, the second lowest (LBW) and highest (HBW) birthweight piglets from both sexes were selected as focal piglets. CTRL piglets were grouped on day 8 p.p. and no split-weaning was applied; TREAT piglets were grouped on day 13 p.p. and the three heaviest non-focal piglets per litter were split-weaned on day 35 p.p. Behaviour and feed intake were measured in focal piglets, and BW and mortality were measured in all piglets. Results showed that: (1) Throughout lactation there were no differences in BW or BW gain between CTRL and TREAT, nor were birthweight × treatment interactions found. (2) After grouping, there were no obvious differences between CTRL and TREAT in feeding and suckling behaviours on day 18, damage scores on snout, ear or tail and skin lesions on day 27, nor were birthweight × treatment interactions found. (3) After split-weaning, in week 6, piglets in TREAT tended to consume less feed than CTRL (P = 0.072). Low birthweight piglets in TREAT consumed numerically less feed and spent numerically less time contacting feed during the day than CTRL piglets. In week 6, there was a significant birthweight × treatment interaction in dry matter milk intake (P = 0.030), caused by a higher milk intake of TREAT-LBW piglets compared with CTRL-LBW piglets. In week 6, TREAT piglets tended to be present more at front and middle teats (P = 0.052) and tended to have lower snout damage scores (P = 0.084) than CTRL piglets. (4) Piglet crushing of all piglets in TREAT tended to be higher during the period when TREAT piglets were not yet grouped i.e. during days 9–14 than CTRL (P = 0.087). To conclude, split-weaning of the heavy piglets increased milk intake particularly of low birthweight piglets but this did not lead to a reduction in BW variation at weaning, as the increased milk intake was largely compensated for by a simultaneous decrease in feed intake.

Effects of Birthweight of Piglets in a Multi-Suckling System on Mortality, Growth Rate, Catch-Up Growth, Feed Intake and Behaviour.

Multi-suckling systems aim to improve animal welfare, but in these systems, a large variation is seen in piglet growth rate. Birthweight (BiW) plays an important role in explaining the variation in body weight (BW) gain of piglets. This study aims to investigate the relationships between BiW and piglet traits up to day 44 postpartum (p.p.). A total of 55 sows were used. The growth rate and mortality were assessed for all piglets. Feed and milk intake, behaviours, and skin lesions were assessed in four focal piglets per litter. Focal piglets were divided into four groups based on their BiW class (high BiW (HBiW) vs. low BiW (LBiW)) and growth rate class (fast vs. slow). Results showed that increased mortality was observed in piglets with a BiW below 1.1 kg. Birthweight was positively related with the number of sucklings (β = 2.8 no./kg of BiW per 7.5 h), corresponding to milk intake (β = 102 g/kg of BiW per day), and to a lesser extent, to the intake of sow feed (β = 44 g/kg of BiW per day) in week 6. Birthweight was positively related with the number of skin lesions (β = 4.3 no./kg of BiW) in week 4. We found no indications that fast-growing LBiW piglets differed from fast-growing HBiW piglets, however, fast-growing piglets of both HBiW and LBiW tended to eat more feed (485 ± 18 vs. 420 ± 17 g/day, p = 0.068), were present less often at teats of alien sows (1.1 ± 0.2 vs. 1.8 ± 0.3, p = 0.010), and had more skin lesions (9.0 ± 0.6 vs. 7.4 ± 0.4, p = 0.047), compared to slow growing piglets. Our study, thus, provides little insight into the traits that affect catchup growth in a multi-suckling environment but increases insight into the differences between fast-growing and slow-growing piglets, regardless of their birthweight class.

Variation in piglet body weight gain and feed intake during a 9-week lactation in a multi-suckling system

A multi-suckling (MS) system for sows and piglets has been developed aiming to improve animal welfare. In this system, large variation in BW gain exists between piglets up to weaning at 9 weeks of age. We aimed to study the causes of variation in BW gain and DM intake of solid feed (DFI) (piglet + sow feed) of piglets during lactation in the MS system. A total of 15 sows and 60 focal piglets across three batches were studied. Individual intake of piglet and sow feed was measured by the dual marker method, and multiple variables were recorded. Multiple linear regression analysis with forward selection was conducted on BW gain and DFI after correcting for piglet sex and batch, using multiple explanatory variables including genetic background, birthweight (BiW), DM feed intake, behaviours and number of skin lesions. These factors jointly explained less than 45 % and 21 % of the variation in BW gain and DFI, respectively. In weeks 2–4, variation in BW gain was mainly explained by BiW (12.0 %) and play and nosing behaviours (7.6 %). In weeks 4–6 and 6–8, it was largely explained by DM intake of piglet feed with 15.1 % and 25.9 %, respectively. Individual variation in DFI in weeks 2–4 was explained by the presence at front and middle teats during suckling bouts (2.9 %), in weeks 4–6 by BiW (9.6 %), and in weeks 6–8 by the number of skin lesions (5.1 %). The unexplained variation in BW gain and DFI warrants further investigation.

A multi-suckling system combined with an enriched housing environment during the growing period promotes resilience to various challenges in pigs

Little is known about the impact of social and environmental enrichment on improving livestock resilience, i.e. the ability to quickly recover from perturbations. We evaluated the effect of an alternative housing system (AHS) on resilience of pigs, as compared to conventional housing (CONV). The AHS consisted of multi-litter housing during lactation, delayed weaning, extra space allowance and environmental enrichment at all times. We assessed recovery to a 2 h-transport challenge, an LPS injection, 2 h-heat stress and a biopsy wound in 96 pigs. Additionally, indicators of long-term “wear and tear” on the body were determined. AHS pigs had better physiological recoveries with quicker returns to baseline in the transport and LPS challenges, showed lower cortisol accumulation in hairs and lower variance in weight gain over the experimental period compared to conventionally-housed (CONV) pigs. They also had higher levels of natural antibodies binding KLH than CONV pigs. Their response to heat stress revealed a different strategy compared to CONV pigs. Taken together, AHS pigs appear to be more resilient and experience less chronic stress. Enhancing welfare by provision of social and environmental enrichment that better meets the behavioural needs of pigs seems to be a promising approach to improve their resilience.

Effects of a Multi-Suckling System Combined With Enriched Housing Post-Weaning on Response and Cognitive Resilience to Isolation.

Improving welfare is still a critical issue in pig husbandry. Upgrades of the housing environment seem to be a promising solution to optimise resilience as a whole, and therefore improve animal welfare. The objective of this study was to evaluate the effect of an alternative housing system to enhance cognitive resilience and also to promote the pigs' welfare. A total of 96 piglets from two contrasted housing systems [alternative housing system (AHS) vs. conventional system (CONV)] was used. The major upgrades of the alternative system were multi-litter housing during lactation, delayed weaning, extra space allowance, and environmental enrichment from birth onwards. To estimate welfare, weight, and feed intake (as a general indicator of performances), the tear staining area (as a chronic stress indicator), behavioural postures, heart rate traits, and saliva cortisol concentration were measured over a 21 h-isolation. To assess cognitive resilience, the pigs were subjected to a maze with a social reward both before and after the isolation challenge and indicators of cognitive abilities were followed. The AHS pigs showed lower cortisol levels and tear staining area before the challenge, demonstrating overall better welfare due to the alternative housing conditions. During the challenge, AHS pigs had a lower heart rate, higher heart rate variability, and higher vagal activity than the CONV pigs, which might indicate a reduced sensitivity to the stressor. AHS pigs appeared to have a better long-term memory tested in a maze. Providing social and environmental enrichments, that fit the satisfaction of the essential needs of the pigs better, appears to be beneficial for pig welfare as a whole. Its effects on cognitive resilience still need to be proven.

Effects of pre-weaning housing in a multi-suckling system on performance and carbohydrate absorption of relatively light and heavy piglets around weaning

The low feed intake and stress associated with abrupt weaning in conventional pig farming often result in poor post-weaning performance, which is related to impaired intestinal function. We investigated effects of housing conditions before weaning on performance around weaning of relatively light and heavy piglets. Before weaning, piglets were housed either with five sows and their litters in a multi-suckling (MS) system or in pens with individually housed sows in farrowing crates (FC). After weaning at 4 weeks of age (day 0), 16 groups of four piglets (two light and two heavy litter-mates) were housed under equal conditions in enriched pens. Mannitol (day −5 and day 5) and galactose (day 5) were orally administered as markers for gastrointestinal carbohydrate absorption, and after 20 min a blood sample was taken (sugar absorption test). In addition, BW, feed intake and faecal consistency as an indicator for diarrhoea, were assessed frequently during 2 weeks post-weaning. Pre-weaning housing, weight class and their interaction did not affect post-weaning faecal consistency scores. Weight gain over 2 weeks did not differ between pre-weaning housing treatments, but MS piglets gained more (0.67±0.12 kg) than FC piglets (0.39±0.16 kg) between days 2 and 5 post-weaning, P=0.02), particularly in the ‘heavy’ weight class (interaction, P=0.04), whereas feed intake was similar for both treatments. This indicates a better utilisation of the ingested feed of the MS piglets compared with the FC piglets in the early post-weaning period. Pre-weaning mannitol concentrations were unaffected by pre-weaning housing, weight class and their interaction. On day 5 post-weaning, however, MS piglets had a lower plasma concentration of mannitol (320 v. 592 nmol/ml, SEM=132, P=0.04) and galactose (91 v. 157 nmol/ml, SEM=20, P=0.04) than FC piglets, regardless of weight class. In conclusion, MS and FC piglets differed in aspects of post-weaning gastrointestinal carbohydrate absorption and in weight gain between days 2 and 5 after weaning, but pre-weaning housing did not affect feed intake, weight gain and measures of faecal consistency over the first 2 weeks after weaning.

Post-weaning social and cognitive performance of piglets raised pre-weaning either in a complex multi-suckling group housing system or in a conventional system with a crated sow

We studied the social and cognitive performance of piglets raised pre-weaning either in a conventional system with a sow in a farrowing crate (FC) or in a multi-suckling (MS) system in which 5 sows and their piglets could interact in a more physically enriched and spacious environment. After weaning at 4 weeks of age, 8 groups of 4 litter-mates per pre-weaning housing treatment were studied under equal and enriched post-weaning housing conditions. From each pen, one pair consisting of a dominant and a submissive pig was selected, based on a feed competition test (FCT) 2 weeks post-weaning. This pair was used in an informed forager test (IFT) which measured aspects of spatial learning and foraging strategies in a competitive context. During individual training, submissive (informed) pigs learned to remember a bait location in a testing arena with 8 buckets (the same bucket was baited in a search visit and a subsequent relocation visit), whereas dominant (non-informed) pigs always found the bait in a random bucket (search visits only). After learning their task, the informed pigs’ individual search visit was followed by a pairwise relocation visit in which they were accompanied by the non-informed pig. Effects of pre-weaning housing treatment were not distinctly present regarding the occurrence of aggression in the FCT and the learning performance during individual training in the IFT. During paired visits, informed and non-informed pigs changed their behaviour in response to being tested pairwise instead of individually, but MS and FC pigs showed few distinct behavioural differences.

Gradual weaning during an extended lactation period improves performance and behavior of pigs raised in a multi-suckling system

We studied effects of two weaning procedures on the development of pigs raised in a multi-suckling (MS) system with five sows and their litters. One MS group was subjected to a gradual weaning treatment during a lactation period of 9 wk, which included forced intermittent-suckling (IS) for 10h/d during the fifth wk of lactation, followed by a 4-wk period in which sows could voluntarily get away from their piglets (IS9 treatment). The other MS group was weaned abruptly at 4 wk of age and was subsequently housed in a nursery (A4 treatment). At 9 wk of age, pigs from both treatments were relocated to a finishing unit, where they were housed in a group of max. 35 pigs per treatment. Five consecutive batches of 10 sows and their litters were studied. Weaning had a more profound impact for the A4 pigs than IS and sow-initiated separation did for the IS9 pigs, demonstrated by a lower weight gain between d 27–33 (0.90±0.08 vs. 1.51±0.06kg/pig, F1,4=25.23, p<0.01), indications of a higher diarrhea occurrence, a distinct peak in belly-nosing behavior and numerically higher levels of aggression and damaging oral manipulation between wk 4–9. For IS9 pigs, weaning seemed to have less impact; feed intake after transition to the finishing unit was similar in both treatments, indicating that IS9 pigs had a more successful transition to a diet of only solid feed, and IS9 pigs showed no growth check, nor behavioral indicators of having difficulty coping with the post-weaning situation. The extended weaning process likely gradually prepared the gastro-intestinal tract to process solid feed, which may explain the better performance of the IS9 pigs. Additionally, benefits of the gradual weaning treatment were reflected in behavioral differences over the entire experiment; between 4–18 wk of age, IS9 pigs overall showed less belly-nosing, less damaging oral manipulation and had fewer lesions related with manipulation and aggression than A4 pigs. This may altogether indicate a less stressed state of the IS9 pigs. To conclude, IS9 pigs coped better with both transitions than A4 pigs did and the gradual weaning treatment had long-term beneficial effects, particularly concerning behavior. Therefore, gradual weaning in a multi-suckling system seems promising for improving piglet performance, behavior and welfare.

Development of piglets raised in a new multi-litter housing system vs. conventional single-litter housing until 9 weeks of age.

This study compared the development until 9 wk of age of piglets raised in either a multi-litter (ML) system or a conventional single-litter (SL) system. The ML system consisted of a multi-suckling system with 5 sows and their litters before weaning, followed by housing in a pen with enrichment in a group of 40 piglets after weaning. In the SL system, piglets were housed with a crated sow before weaning, followed by postweaning housing in groups of 10 littermates in a standard pen. Fifty litters were used in 5 batches and piglets were weaned at 4 wk of age. Preweaning mortality was higher in the ML system than in the SL system (3.22 ± 0.42 vs. 1.52 ± 0.25 piglets per litter, < 0.01), mainly due to crushing before grouping of litters. Litter size at grouping did not differ between systems. ML piglets showed more feed-directed behavior at 2 wk of age (6.80 ± 0.96 vs. 2.35 ± 0.59, < 0.01), suggesting an earlier start of feed exploration, possibly due to social learning from the floor-fed sows and other piglets. Moreover, before weaning, ML piglets showed less damaging oral manipulation (e.g., tail biting) than SL piglets (1.4 ± 0.2 vs. 3.6 ± 0.3 freq/h, < 0.001), which was likely related to the more enriched environment in the ML system. After weaning, ML piglets ate 81% more feed between d 1 and 2 (0.29 ± 0.02 vs. 0.16 ± 0.03 kg/piglet, < 0.01) and had an 82% higher weight gain until d 5 than SL piglets (1.35 ± 0.21 vs. 0.75 ± 0.17 kg, < 0.05) despite a similar weaning weight (ML: 8.4 ± 0.2 kg, SL: 8.3 ± 0.2 kg). Within the first 2 wk after weaning, ML piglets had a lower fecal consistency score (0.27 ± 0.03 vs. 0.39 ± 0.03, < 0.05), indicating a lower occurrence of diarrhea compared with SL piglets. Over the entire 5-wk postweaning phase, ML piglets had a 24% higher weight gain ( < 0.05) and showed more play behavior (4.0 ± 0.3 vs. 2.8 ± 0.3 freq/h, < 0.05) and less damaging oral manipulation (1.8 ± 0.3 vs. 3.5 ± 0.4 freq/h, < 0.01) than SL piglets. These results are probably explained by a combination of the differences in preweaning development, early postweaning performance, and postweaning environment, with a larger and more diverse social group and more physical enrichment in the ML pen. To summarize, provided that preweaning mortality can be reduced, the ML system seems promising for raising robust piglets with better welfare, indicated by a better preweaning behavioral development, improved transition to the postweaning phase, and better postweaning performance.

A review of sow and piglet behaviour and performance in group housing systems for lactating sows

Commercial use of group housing systems for lactating sows is limited, but the recent transition to group housing during gestation in the EU may result in a renewed interest in such systems. Therefore, this review aims to identify key factors that may contribute to the success or failure of group housing of lactating sows in comparison with individual housing by describing the variety in group housing systems and discussing animal behaviour and performance compared with individual housing. Group housing systems can be divided in multi-suckling (MS) systems, in which sows are grouped with their litters, and get-away (GA) systems, which include a separate communal area accessible to sows only. These systems differ in many aspects regarding management and layout but, compared with individual housing, generally provide more environmental complexity, more freedom of movement for the sows and more freedom to express behaviours related to, for example, maternal care and social interactions. Group housing poses several risks, such as disrupted nursing and an increased level of crushing during the MS phase, and in the GA systems there is a risk for early cessation of nursing. On the other hand, pre-weaning mingling of litters clearly benefits piglet social development and may improve adaptation to the post-weaning situation. In addition, group-housed sows may show lactational ovulation, which provides opportunities for insemination during an extended lactation period, which benefits the piglets. Gradual transitions in social and physical environment around gestation, farrowing, grouping and weaning seem to be key success factors for group housing systems during lactation. In addition, selection of suitable sows and quality of stockmanship seem important.

Alternative farrowing accommodation: welfare and economic aspects of existing farrowing and lactation systems for pigs

There is growing societal pressure, expressed through government legislation and consumers’ purchasing choices, to abolish livestock systems considered detrimental to farm animal welfare. Such systems include farrowing crates, which are behaviourally and physically restrictive for sows. Therefore, identifying less restrictive farrowing systems for commercial implementation has become an important focus of pig research. Despite numerous attempts to develop indoor alternatives to crates, there is as yet no universal acceptance of such systems at the commercial level. The primary concern is piglet survival, because often favourable figures are reported at the experimental level, but not replicated in commercial evaluation. Alternative farrowing systems should equal or surpass survival levels in conventional systems and perform consistently across a range of farm circumstances for widespread commercial implementation. In addition, it is important that alternatives consider ease of management, operator safety and economic sustainability. Utilising a large database of literature, 12 existing alternative indoor systems were identified and compared against each other, conventional crates and outdoor systems. An assessment of how well alternative systems satisfy the design criteria for meeting animals’ biological needs was carried out by developing a welfare design index (WDI). The physical and financial performance of these systems was also evaluated and summarised. The derived WDI yielded values of 0.95 for conventional crates, with higher scores for commercial outdoor systems of 1.10 and indoor group farrowing or multi-suckling systems (e.g. Thorstensson = 2.20). However, the high total piglet mortality (23.7% ± s.e. 2.26) in indoor group systems compared with conventional crates (18.3% ± s.e. 0.63) and outdoor systems (17.0% ± s.e. 2.05), together with the added capital cost (92% more than conventional crates, 249% more than commercial outdoor huts), mainly as a result of extra building space provided per animal, question their feasibility to deliver from an economic perspective. Designed pen systems offered the best compromise, scoring 1.64 from the WDI, with a total piglet mortality of 16.6% (±s.e. 0.88) and capital costs and labour input more comparable to farrowing crates (17.5% more than crates). The critical review of different systems was hampered by the lack of comprehensive data and detailed system descriptions. When attempting to assess welfare and economic attributes of systems, there are certain caveats that require discussion, in particular weighting of the contribution of different design attributes to pig welfare, the relative importance of the sow and her piglets and the many potential confounding factors that arise. Also, when judging any system, it must be emphasised that the maternal characteristics of sows and the quality of stockpersonship will be integral to its success.

Effect of milk deprivation during the lactation period on performance and digestive enzyme activities of the piglets following weaning

Post-weaning performance of piglets from systems where lactation is disrupted (e.g. from multisuckling systems) is superior to conventionally reared piglets. The objective of this study was to establish whether restricted growth prior to weaning caused by disruption of suckling was an important factor in post-weaning performance and also whether there were related changes in gastro-intestinal development. Ten litters of eight piglets were used in a split-plot design. Half of each litter (limited suckling, LS) had suckling disrupted by separation from their dam for 7 h/day from day 14 to 28 after farrowing. The remainder of each litter was allowed to suck normally (normal suckling, NS). The same amount of creep feed was offered to LS piglets as consumed by NS littermates on the previous day. There were no differences in weight between LS and NS piglets at 14 days of age, but restricting access to the sow reduced weaning weight at 28 days of age (7.96 v. 9.00 kg; LS v. NS; P < 0.01; s.e.d. 0.23). Feed intakes were greater for LS than NS piglets over the first 28 days post weaning, particularly in the 1st week after weaning when feed efficiency was also improved (0.91 v. 0.62 kg gain per kg feed; P < 0.01; s.e.d. 0.08). As a result, LS piglets grew more rapidly in the first 28 days post weaning, particularly in the first 7 days after weaning. Subsequent performance to 8 weeks was similar for both groups. Digestive organ weights were not different at 2 and 9 days after weaning; nor were small intestine specific enzyme activities significantly different ( P>0.05). Pancreatic trypsin activity was, however, greater ( P < 0.01) for LS pigs on both days 2 and 9 post weaning. In conclusion the restriction of growth as a result of limited suckling itself is an important factor in determining post-weaning performance and may be related to development of pancreatic trypsin activity.

The influence of parity on lactational oestrus in a multisuckling system for sows

The occurrence of ovulation in the sow after parturition is usually inhibited for the duration of suckling. A system of management in which lactating sows are mated and conceive, therefore routinely commencing a successful pregnancy concurrent with lactation, would obviate the need for early weaning of piglets and promote adoption of economic systems incorporating more extensive lactation housing. Previous studies have shown that first parity sows rarely show ovulation during lactation when group-housed in multisuckling systems with multiparous sows, and suggested that reduced food intake through social competition and/or higher suckling intensity were responsible for this (Hulten, 1997). The object of this experiment was to investigate, in a more controlled way, the factors contributing to this parity effect by removing the possibility of social interactions between primiparous and multiparous sows, and investigating possible dietary influences within parity.

Effect of familiarity with the environment on the behaviour and performance response of sows and piglets to grouping during lactation

To determine whether the disruption in suckling patterns and cross-suckling which are observed in multisuckling systems could be reduced by modifying pen design to permit prior familiarity of animals with the environment, 32 Large White×Landrace sows and litters were allocated between two treatments, each with four replicate groups of four sows and litters. On Day 7 after farrowing, T1 sows and litters were moved from individual farrowing crates to a modified multisuckling pen, where each sow and her piglets were enclosed in an individual pen, whilst T2 sows and litters remained in the farrowing house. Grouping occurred on Day 14; in T1 the gate behind each individual pen was opened to allow the animals voluntary access to a communal area. T2 animals were moved directly from the farrowing house and grouped in an unfamiliar multisuckling pen of the same size with conventional open layout and a single large creep area for the piglets. Overall mortality rate in the two systems was not significantly different, but more piglets tended to be crushed in each treatment in the week following first transfer to the experimental pens ( P<0.10). Frequency of suckling attempts (1.47 vs. 0.95 per hour, S.E.D. 0.05, P<0.01) and proportion of suckling attempts which resulted in milk letdown (0.60 vs. 0.40, S.E.D. 0.07, P=0.06) were lower for T2 than T1 on the day of grouping. The proportion of piglets cross-suckling per litter after grouping was greater in T2 (0.58 vs. 0.22, S.E.D. 3.14, P<0.01). Piglets in T1 spent a greater proportion of time close to their own mother (e.g. 0.45 vs. 0.12, S.E.D. 0.082, P<0.05 on Day 14). Piglet growth rate was significantly reduced in T1 between Day 7 and 14 (211 vs. 260 g/day, S.E.D. 15.3, P<0.01) but only slightly better than T2 after grouping (221 vs. 213 g/day, S.E.D. 7.2, for Days 14–28). After weaning, performance did not differ significantly between piglets from the two systems. Familiarity with the new environment before grouping, and/or greater structural complexity within the pen, therefore reduced the disruption in suckling behaviour after grouping and reduced the incidence of cross-suckling, but did not yield performance benefits.

Cross-suckling and associated behaviour in piglets and sows

In order to reveal factors that cause piglets to become cross-sucklers and to study the behaviour associated with cross-suckling, the nursing and suckling behaviour of sows and piglets was first observed in a farrowing pen 4 to 7 days after farrowing and later in pens for group housed lactating sows (i.e., from day 5 to 14 after moving to the multi-suckling pen which occurred on day 11 after birth). Three groups of six sows and their litters (189 piglets in total) were studied. About 34% of all piglets were seen cross-suckling at least once. However, it appear that in the multi-suckling system there were at least two groups of individuals present; those that suckled alien sows habitually (16% of the piglets cross-suckled more than five times) and those that cross-suckle only occasionally (84% of the piglets cross-suckled between 0 and 4× including). Cross-suckling was found to be associated with low milk yield of the mother in the farrowing pen. The cross-suckling piglets compensated for the low milk yield by cross-suckling a sow with a higher milk yield and by moving to a teat with a higher milk yield. Interestingly, this study showed that sows distinguished between their own and other piglets, as the sows showed more aggression towards both cross-suckling and cross-fostered piglets.

Performance and behaviour of lactating sows and piglets in crate and multisuckling systems: a study involving European White and Manor Meishan genotypes

AbstractTwo experiments were conducted to compare the performance and behaviour of lactating sows and piglets in farrowing pens with crates or multisuckling systems (group housing of sows and piglets in the second half of lactation). All sows were farrowed in commercial accommodation based on farrowing pens with crates. In experiment 1, fifteen purebred Landrace or Large White sows and litters were recorded in crates as a control (C). Three replicates of six sows and litters were recorded in a multisuckling system (M) in which the sows and litters were group-housed from 2 weeks after farrowing until weaning. Experiment 2 involved 30 Manor Meishan sows (0·25 Meishan genes). The sows and litters were arranged into three treatments and two replicates with five sows and litters in each group. Treatments comprised a control farrowing pen with crate system and two multisuckling systems differing in degree of accessibility of the piglet creep area. Multisuckling 1 (Ml) had a solid creep front with an open doorway (0·5 X 0·9 m) for piglet access. In multisuckling 2 (Ml), the lower 30 cm of the solid creep front was removed to facilitate piglet access and allow visual contact with the sows. Piglets were weaned at 31 days in experiment 1 and 29 days in experiment 2. After weaning, piglets were moved to controiled-environment, fully slatted accommodation and monitored for 7 days in experiment 1 and for 12 days in experiment 2. Mortality rate in the two systems was not significantly different. However, some piglets in the M system were crushed after grouping (0·3 and 0·2 piglets per litter in experiments 1 and 2, respectively). Growth rate was reduced in M piglets in the week after grouping (256, 184 (s.e.d. 21·4) g/day, P &lt; 0·01 for C and M respectively in experiment 1 and 243, 150 and 209 (s.e.d. 12·2) g/day, P &lt; 0·01 for C, Ml and Ml respectively in experiment 2) but was higher after weaning (271, 313 (s.e.d. 35·7) g/day, P &gt; 0·05 for C and M respectively in experiment 1 and 148, 280 and 222 (s.e.d. 15·0) g/day, P &lt; 0·01 for C, Ml and Ml respectively in experiment 2). In consequence, piglet live weight at 1 week after weaning did not differ between treatments (9·33, 9·74 (s.e.d. 0·36) kg for C and M respectively in experiment 1 and 9·30, 914 and 9·53 (s.e.d. Oil) kg for C, Ml and Ml respectively in experiment 2). Sucking behaviour of M piglets in both experiments was severely disrupted (P &lt; 0·01) on the day of grouping and the day after grouping. Despite synchronized suckling, M litters had a high incidence of cross suckling (&gt; 50%) throughout lactation. M piglets spent more time than C outside the creep area, even with a more open creep (Ml). The Meishan sows tended to be more docile and fought less at grouping than the white breeds (0·39 and 1-71 fights per sow per h). Immediately after weaning, C piglets spent more time fighting (8·0 and 1·0 (s.e.d. 0·99) % of time, P &lt; 0·01 for C and M respectively in experiment 1 and 4·51, 0·09 and 0·09 (s.e.d. 019) % of time, P &lt; 0·01 for C, Ml and M2 respectively in experiment 2). These studies demonstrate that, in a multisuckling system, piglets achieved similar overall growth rate to C piglets, since both received checks in growth at different times and for different reasons.

Effect of familiarity with the environment on the behaviour and performance response of sows and piglets grouped during lactation

Disruption in suckling patterns and cross-suckling was observed to a high degree following grouping of litters in a multisuckling system, resulting in a reduction in piglets’ performance before weaning (Wattanakul et al, 1995). Relocation of the sows between crates while litters were grouped in a farrowing house also increased the incidence of cross-suckling, whereas grouping the piglets without relocating the sows did not (Wattanakul et al, 1996). Familiarity with the home location before grouping might therefore reduce the incidence of cross-suckling in a multisuckling system. This experiment was designed to investigate the effects of familiarity with a suckling place prior to grouping on suckling behaviour and performance of piglets.

Effect of milk deprivation during the lactation period on performance and digestive enzyme activities of the piglets following weaning

Piglets from a multisuckling system, which experienced disrupted suckling during the lactation period, had a higher feed intake following weaning and experienced less check in growth compared to weaned piglets from a conventional crate system (Wattanakul et al, 1995). To investigate the mechanisms underlying the improved post weaning performance of these piglets, the role of growth restriction resulting from disruption of suckling was assessed, under standardised environment conditions.

A comparison of performance and behaviour of Meishan crossbred sows and piglets in crate and multisuckling systems

The farrowing crate has been designed to prevent crushing of newborn piglets but restricts sow movement throughout lactation with the result of sow problems such as stereotypies and leg weakness. To improve the sows' and piglets' welfare and meet the requirements of commercial production, the combination of individual farrowing crates, to control the piglet mortality in the first stage, with group housed multisuckling systems to restore the social environment of the sow have been investigated (Petchy, Dodsworth and English, 1978; Bryant, Rowlinson and Steen, 1983; Andersson and Andreasson, 1992; Sinclair, 1993). The change of environment can, however, lead to problems of the sows fighting on the day of mixing and possible increase in piglet mortality by crushing (Andersson and Andreasson, 1992, Sinclair, 1993). The use of a multisuckling system with Meishan crossbreds may utilise the benefits of docile temperament, enhance pig welfare and meet the economic requirements of commercial production.

A comparison of performance and behaviour of Meishan crossbred sows and piglets in crate and multisuckling systems

The farrowing crate has been designed to prevent crushing of newborn piglets but restricts sow movement throughout lactation with the result of sow problems such as stereotypies and leg weakness. To improve the sows' and piglets' welfare and meet the requirements of commercial production, the combination of individual farrowing crates, to control the piglet mortality in the first stage, with group housed multisuckling systems to restore the social environment of the sow have been investigated (Petchy, Dodsworth and English, 1978; Bryant, Rowlinson and Steen, 1983; Andersson and Andreasson, 1992; Sinclair, 1993). The change of environment can, however, lead to problems of the sows fighting on the day of mixing and possible increase in piglet mortality by crushing (Andersson and Andreasson, 1992, Sinclair, 1993). The use of a multisuckling system with Meishan crossbreds may utilise the benefits of docile temperament, enhance pig welfare and meet the economic requirements of commercial production.