Intermittent suckling with or without co-mingling of non-littermate piglets before weaning improves piglet performance in the immediate post-weaning period when compared with conventional weaning

Background: In this experiment, intermittent suckling (IS) with or without the co-mingling (CoM) of piglets was studied as a method to stimulate solid feed intake and reduce post-weaning stress. Methods: Three weaning regimes using 30 multiparous sows were compared: (1) conventional weaning (CW) (n = 10 litters), where piglets had continuous access to the sow until weaning (d 0, farrowing = d −25 relative to weaning); (2) intermittent suckling (IS) (n = 10 litters), where piglets were separated from the sow for 8 h/d starting at d −7 (relative to weaning); and (3) intermittent suckling with co-mingling (ISCo) (n = 10 litters) where IS started at d −7 and two litters were housed together during separation and then returned to their original sow. Ad libitum creep feed was available from d −17. At weaning pigs were housed in pens of 11 pigs, 27 pens in total. The ISCo treatment was divided in half to examine effects of different mixing strategies after weaning. Half of the ISCo litters were kept in familiar groups (ISCoF, familiar, n = 4) and the other half were mixed within treatment resulting in groups of unfamiliar pigs (ISCoNF, not familiar, n = 5), the same as IS (n = 9) and CW (n = 9) treatments. Results: The ISCo piglets ate more creep feed in the week before weaning (P < 0.01), but also showed more aggressive and manipulative behaviour on first day of CoM compared with CW piglets (P < 0.05). IS with or without CoM increased exploratory and play behaviour on the first day of treatment intervention (P < 0.001) and increased sleeping behaviour on the last day of treatment intervention compared with CW (P < 0.001). Mixing strategy at weaning had an effect on performance data with the highest growth and feed intake seen in ISCoF pigs 2 to 8 d after weaning (P <0.001). IS and ISCoNF pigs also grew faster and ate more than CW pigs 2 to 8 d after weaning (P < 0.001). Post-weaning injury scores suggested reduced aggression in ISCo as evidenced by reduced redness (skin irritation) (P < 0.05), and a tendency for ISCo to have less scratches than CW (P < 0.1). The IS pigs slept the most and displayed less manipulative behaviours on the day of weaning and plasma haptoglobin levels remained low in IS pigs after weaning (P ≤ 0.01). Conclusions: Both intermittent suckling techniques improved production indices in the immediate post-weaning period. However, the addition of co-mingling before weaning in combination with grouping familiar pigs together after weaning improved performance in an additive manner

Improving welfare and production in the peri-weaning period: Effects of co-mingling and intermittent suckling on the stress response, performance, behaviour, and gastrointestinal tract carbohydrate absorption in young pigs

We investigated the effect of different pre-weaning interventions on performance, aspects of behaviour, and selected neuroendocrine, inflammatory and immune indices in 593 weanling pigs (59 litters, weaning age 22 ± 1.7). Measurements were taken at various time points two weeks before and after weaning. Sugar absorption tests (20% mannitol and 20% galactose solutions) were used to assess gastrointestinal tract (GIT) absorptive capacity. One week before weaning, litters were either co-mingled (CoM) for 8 h daily with another litter or not co-mingled (NoCoM). Half of the litters were also subjected to intermittent suckling (IS) involving separation from their sow for 8 h daily and the other half remained with their sow (NoIS). Hence, four treatments were produced in a 2×2 factorial design; (1) CoM IS (n = 16 litters), (2) CoM NoIS (n = 14 litters), (3) NoCoM IS (n = 16 litters), (4) NoCoM NoIS (n = 13 litters). Measurements are compared within each of the main effects (CoM or IS) unless otherwise stated. Acute weaning stress was evidenced by increases in cortisol, haptoglobin and N: L ratios when data were combined (P < 0.001). However, there were tendencies (P < 0.1) for lower cortisol in IS pigs and higher N: L ratios in CoM pigs at weaning. While CoM did not affect performance before weaning, growth (P < 0.05), feed intake (P < 0.05) and body weight (P < 0.05) were reduced in CoM pigs 7-14 days after weaning. One week of IS before weaning improved feed intake before weaning (P < 0.01), resulting in better growth (P = 0.01) and a tendency (P < 0.1) for a higher feed intake 2-7 days after weaning. Co-mingled piglets had more scratches 4 days before weaning (P < 0.001), but tended to have fewer scratches 2 days after weaning (P < 0.1). Pigs exposed to either IS or CoM displayed more sleeping behaviour the day after weaning (P < 0.01 and P < 0.001). A higher mannitol absorption was evident in CoM NoIS pigs 3 days after weaning (P < 0.01), and galactose absorption was reduced in IS pigs 3 days before weaning (P < 0.05) and tended to be reduced 3 days after weaning (P < 0.1), likely reflecting a GIT adaptive response. Overall, despite improvements in mannitol absorption and behaviour, there was no beneficial effect of CoM on performance after weaning. Alternatively, IS improved behaviour and performance during the first week after weaning

Intermittent suckling in combination with an older weaning age improves growth, feed intake and aspects of gastrointestinal tract carbohydrate absorption in pigs after weaning

This study tested the hypothesis that intermittent suckling (IS) with or without an older weaning age would improve post-weaning gastrointestinal tract (GIT) carbohydrate absorptive capacity in pigs while reducing post-weaning stress and aspects of the inflammatory response. Three weaning regimes using primiparous sows were compared: (1) conventional weaning (CW28) (n = 22), where piglets were weaned conventionally at day 28; (2) IS28 (n = 21), where IS started at day 21 until weaning at day 28; and (3) IS35 (n = 21), where IS started at day 28 until weaning at day 35. Sugar absorption tests (10% mannitol or 10% galactose) were used to measure GIT absorptive capacity. All measured parameters were compared in relation to weaning across treatments (i.e., different physiological ages were compared). The IS35 pigs grew fastest in the 12 days after weaning (p < 0.01) and had the highest solid feed intake before and after weaning (p < 0.05). Irrespective of treatment, pre-weaning mannitol levels were higher than post-weaning levels (p < 0.01), whereas post-weaning galactose levels were highest in IS35 pigs (p < 0.01). Cytokine data did not show any treatment effects. In conclusion, these data suggest that IS in combination with an older weaning age (day 35) improved post-weaning adaptation as evidenced by improvements in performance measures and galactose absorption. However, IS28 did not improve post-weaning performance

Intermittent suckling influences the performance of pigs before and after weaning

The simultaneous and abrupt changes at weaning cause a growth check characterised by sub-optimal performance, marked changes to the gastrointestinal tract, and increased susceptibility to enteric diseases (Pluske et al., 1997). Intermittent suckling (IS) is a regimen in which the sow is removed from her piglets for a period of time each day before weaning. Previous studies have shown that IS reduces the postweaning growth check by stimulating feed intake in lactation (Kuller et al., 2004), but the impacts of duration and length of separation have not been fully evaluated. The hypothesis tested in this study was that piglets separated from their dam for eight hours per day for seven d in the week before weaning would perform better after weaning compared to piglets in conventional weaning regimens

Gastrointestinal tract (gut) health in the young pig

An optimally functioning gastrointestinal tract (GIT) clearly is of importance to the overall metabolism, physiology, disease status and performance of pigs of all stages of growth and development. Recently, the 'health' of the GIT ('gut health') has attracted much attention despite the lack of a clear definition to the term or its aetiology, although in broad terms, 'gut health' encompasses a number of physiological and functional features including nutrient digestion and absorption, host metabolism and energy generation, a stable and appropriate microbiota/microbiome, defence mechanisms including barrier function and mucosal immune mechanisms, and the interactions between these components. 'Gut health' in the newly-weaned (young) pig is of obvious interest due to changes in GIT structure and function associated with the post-weaning transition, and more recently to the upsurge in interest in different feed additives as dietary alternatives/replacements caused by bans/reductions in certain antimicrobial compounds being available in some parts of the world. In the presence of enteric disease(s) after weaning, a deterioration in 'gut health' may be synonymous to the overall health of the pig, and although some direct relationships can be drawn between pig performance and efficiency and a 'healthy' GIT, sometimes this connection is subtler and less obvious, especially in the absence of overt enteric disease(s). The factors and conditions involved in 'gut health' are multifactorial, complex, often poorly described and sometimes incorrectly interpreted, although it is evident that perturbations of the GIT can cause an imbalance and disturb the generalized homeostasis. In addition to any enteric diseases or conditions that might arise as a result of these disturbances, other influences will also impact such as the responses occurring in the GIT in the period immediately after weaning, any changes that might occur after a change in diet, and (or) disruptions to meal patterns and hence the flow of nutrients. Ultimately, 'gut health' represents the outcome of the GIT in response to its capacity and ability to respond and adapt to the insults and challenges it encounters

Impacts of feeding organic acid-based feed additives on diarrhea, performance, and fecal microbiome characteristics of pigs after weaning challenged with an enterotoxigenic strain of Escherichia col

Post weaning diarrhea (PWD) caused by enterotoxigenic strains of E. coli (ETEC) remains a major problem in the industry, causing decreases in performance and survival of weaned pigs. Traditionally, antimicrobials have been used for its mitigation/control. This study tested the hypothesis that a combination of two organic acid (OA)-based commercial feed additives, Presan FX [an OA, medium-chain fatty acid (MCFA) and phenolic compound-based product] and Fysal MP (free and buffered OA based on formic acid), would reduce PWD and improve post-weaning performance in pigs challenged with an F4-ETEC. This combination was assessed against a Negative control diet without any feed additives and a diet containing amoxicillin. Combined with a reduction in temperature during the infection period, inoculation with F4-ETEC resulted in 81% of pigs developing diarrhea, but with no differences between treatments (P > 0.05). However, between days 14 to 20 of the study and due to colonization by Salmonella serovars, pigs fed the combination of Presan FX and Fysal MP showed less (P = 0.014) diarrhea commensurate with a lower (P = 0.018) proportion of Salmonella numbers relative to total bacterial numbers. This caused less (P = 0.049) therapeutic antibiotic administrations relative to the diet with amoxicillin during this time. The diversity of bacteria within amoxicillin-treated pigs was lower (P = 0.004) than the diversity in control or Presan FX + Fysal MP-treated pigs (P = 0.01). Pair-wise comparisons showed that amoxicillin-treated pigs had altered (P < 0.001) fecal microbial communities relative to both Presan FX + Fysal MP-treated pigs and control pigs. Amoxicillin-treated pigs were characterized by an increased abundance of bacterial families generally linked to inflammation and dysbiosis in the gastrointestinal tract (GIT), whereas Presan FX + Fysal MP-treated pigs had an increased abundance of bacterial families considered beneficial commensals for the GIT. Control pigs were characterized by an increased abundance of Spirochaetaceae associated with healthy piglets, as well as bacterial families associated with reduced feed intake and appetite. The combination of two OA-based feed additives did not reduce the incidence of F4 ETEC-associated diarrhea nor enhance performance. However, the combination markedly reduced diarrhea caused by Salmonella that occurred following the ETEC infection, commensurate with less therapeutic administrations relative to the diet with amoxicillin

Associations between gastrointestinal-tract function and the stress response after weaning in pigs

Psychosocial stress is a major factor driving gastrointestinal-tract (GIT) pathophysiology and disease susceptibility in both humans and animals. Young weaned pigs typically undergo psychosocial and environmental stressors associated with production practices, including separation from their dam, mixing and crowding stress, transport and changed temperature and air-quality parameters, all of which can have significant deleterious impacts not only on performance but also on GIT structure and function, and, therefore, pig health and welfare. Strategies addressing some of these issues are explored in the current review, as well as discussion pertaining to sexual dimorphism in young pigs linked to stressful experiences, with young female pigs seemingly adversely affected more than their male counterparts. However, mechanisms governing susceptibility to stress-induced GIT functionality and disease remain inadequately understood

Lactational oestrus and reproductive performance following a delayed limited nursing schedule in primiparous sows

With conventional lactation management, sows only conceive after weaning. However, intermittent suckling (IS) enables follicle growth and ovulation during lactation by reducing the suckling-induced inhibition of gonadotrophins. The current study evaluated IS regimes initiated at Day 21 or Day 28 post farrowing compared to conventional weaning on Day 28, in primiparous sows. Sows (Large White and Large White x Landrace) were randomly allocated to Control (C28; n = 44), IS21 (n = 29) and IS28 (n = 34) treatments at Day 20. Sows in IS21 and IS28 were subjected to intermittent suckling from Day 21 or Day 28 post farrowing. During IS, sows were separated from their piglets for 8 h daily, then weaned 7 d later at Day 28 and Day 35 respectively, whereas piglets in the C28 treatment had continuous access to sows until weaning at Day 28. Percentage of IS sows that showed oestrus during lactation was 59% (16/27) in IS21 and 72% (21/29) in IS28 (P > 0.05). Cumulatively over the lactation and 7 d post-weaning period, 93% of IS21, 85% of IS28 and 93% (31/33) of C28 sows showed oestrus (P > 0.05). Pregnancy rate at Day 30 post mating, for sows that were mated during lactation was 93% (15/16) in IS21 and 95% (20/21) in IS28, whereas C28 sows had a 96% (30/31) pregnancy rate (P > 0.05). No difference was found in the time of oestrus relative to weaning (C28) or onset of IS (IS21 and IS28) (P > 0.05). The IS sows that did not ovulate before weaning all showed oestrus within 7 days from weaning, and the weaning to oestrus interval was similar to control sows (P > 0.05). However, for all IS sows (across IS treatments) that showed lactational ovulation, LH secretion pattern at onset of IS was different (P 0.05). The present study showed that in modern primiparous sows, lactational oestrus can be induced and pregnancy can be maintained at a similar rate and producing comparable subsequent litter sizes to conventionally weaned sows when IS commenced at four weeks post farrowing. However, when IS commences at three weeks post farrowing, this may affect the percentage of sows showing oestrus in lactation and may potentially influence subsequent litter size

In Search of Paradigms: Identifying the Theoretical Foundations of the IS Field

The goal of this paper is identify the theoretical foundations of the IS field. Currently there is a lack of consensus about what the core IS theories are, or even if we have any at all. If we do, they certainly don’t appear in IS curricula or textbooks as they do in more mature disciplines. So far, most of the debate on this issue has been conducted at a subjective and prescriptive (normative) level. We attempt to broaden the debate by taking a descriptive (positive) approach, using relatively objective data. We do this by consulting the “geological record”: the pattern of citations in the leading IS journals. We use a combination of quantitative and qualitative techniques to identify the most influential theories in the IS field. The results of our analysis are surprisingly positive, especially in the light of warnings about IS being overly dependent on reference disciplines (a discipline with no theory to call its own) and being obsessed with research methodology (emphasising how to research at the expense of what to research). This suggests that the negative views often expressed about the progress of IS may be unjustified and that its development has followed the normal evolutionary pattern of any research field. Being aware of our theoretical foundations will help clarify our disciplinary identity and guide teaching and scholarship