Effect of dietary tall oil fatty acids and hydrolysed yeast in SNP2-positive and SNP2-negative piglets challenged with F4 enterotoxigenic Escherichia coli.

Reduction of post-weaning diarrhoea caused by ETEC is a principal objective in pig farming in terms of welfare benefits. This study determined the effects of genetic susceptibility and dietary strategies targeting inflammation and fimbriae adherence on F4-ETEC shedding and diarrhoea in weaned piglets in an experimental challenge model. A DNA marker test targeting single nucleotide polymorphism 2 (SNP2) identified piglets as heterozygous (SNP2+, susceptible) or homozygous (SNP2-, resistant) to developing F4ac-ETEC diarrhoea. A total of 50 piglets, 25 SNP2+ and 25 SNP2-, were weaned at 30 days of age and equally distributed to different treatments (n = 10): Positive control (PC): piglets fed with a negative control diet and provided with colistin via drinking water; Negative control (NC): piglets fed with a negative control diet; Tall oil fatty acids (TOFA): piglets fed with a negative control diet + 1.0 g TOFA/kg feed; Yeast hydrolysate (YH): piglets fed with a negative control diet + 1.5 g YH/kg feed derived from Saccharomyces cerevisiae; and Combination (COM): piglets fed with a negative control diet + 1.0 g TOFA and 1.5 g YH/kg feed. On day 10 post-weaning, all piglets were infected with F4-ETEC by oral administration. Piglets fed with PC, TOFA, YH or COM had a lower faecal shedding of F4-ETEC than NC piglets (P < 0.001), which was also shorter in duration for PC and TOFA piglets than for NC piglets (P < 0.001). Piglets in PC, TOFA, YH and COM had a shorter diarrhoea duration versus NC when classified as SNP2+ (P = 0.02). Furthermore, PC, TOFA and YH piglets grew more than NC and COM piglets in the initial post-inoculation period (P < 0.001). In addition, the level of faecal F4-ETEC shedding and the percentage of pigs that developed F4-ETEC diarrhoea (72 vs. 32%, P < 0.01) following infection were higher, and the duration of F4-ETEC diarrhoea longer (2.6 vs. 0.6 days, P < 0.001), in SNP2+ piglets than in SNP2- piglets, and led to reduced growth performance (P = 0.03). In conclusion, piglets fed with TOFA, YH or their combination, irrespective of their SNP2 status, are more resilient to F4-ETEC infection. Moreover, SNP2+ piglets show a higher level of F4-ETEC shedding and diarrhoea prevalence than SNP2- piglets, confirming an association between SNP2 and F4ac-ETEC susceptibility.

Using Nutritional Strategies to Shape the Gastro-Intestinal Tracts of Suckling and Weaned Piglets.

This is a comprehensive review on the use of nutritional strategies to shape the functioning of the gastro-intestinal tract in suckling and weaned piglets. The progressive development of a piglet's gut and the associated microbiota and immune system offers a unique window of opportunity for supporting gut health through dietary modulation. This is particularly relevant for large litters, for which sow colostrum and milk are insufficient. The authors have therefore proposed the use of supplemental milk and creep feed with a dual purpose. In addition to providing nutrients to piglets, supplemental milk can also serve as a gut modulator in early life by incorporating functional ingredients with potential long-term benefits. To prepare piglets for weaning, it is important to stimulate the intake of solid feed before weaning, in addition to stimulating the number of piglets eating. The use of functional ingredients in creep feed and a transition diet around the time of weaning helps to habituate piglets to solid feed in general, while also preparing the gut for the digestion and fermentation of specific ingredients. In the first days after weaning (i.e., the acute phase), it is important to maintain high levels of feed intake and focus on nutritional strategies that support good gastric (barrier) function and that avoid overloading the impaired digestion and fermentation capacity of the piglets. In the subsequent maturation phase, the ratio of lysine to energy can be increased gradually in order to stimulate piglet growth. This is because the digestive and fermentation capacity of the piglets is more mature at this stage, thus allowing the inclusion of more fermentable fibres. Taken together, the nutritional strategies addressed in this review provide a structured approach to preparing piglets for success during weaning and the period that follows. The implementation of this approach and the insights to be developed through future research can help to achieve some of the most important goals in pig production: reducing piglet mortality, morbidity and antimicrobial use.

Effects of Creep Feed Provision on Behavior and Performance of Piglets Around Weaning.

Creep feed provision may ease weaning, hence we determined the impact of providing fibrous creep feed before weaning and adding this feed to the post-weaning diet on piglet behavior and performance. Pre-weaning, litters with on average 12 piglets were given creep feed (CF, n = 12 litters) or not (NF, n = 10 litters). Post-weaning, piglets (n = 8 pens with 4 piglets/treatment) were given a weaner diet (CON) or weaner diet supplemented with creep feed (CS). Behaviors were scored in the home pen at d11, 16, 22 and 27 after birth and at wk 1 and 2 post-weaning. Feed intake, growth and fecal consistency were measured up to d14 post-weaning. A blood sample was taken at d2, 15 and 29 after birth and d2, 5 and 14 post-weaning. CF-piglets consumed on average 397 ± 71 g creep feed before weaning. CF-piglets grew faster in the last week before weaning than NF-piglets (249 ± 7 vs. 236 ± 11 g/d, F (1, 18) = 5.81, P = 0.03). However, CF- and NF-piglets did not differ in weaning weight, within-litter coefficient of variation in weaning weight, behaviors in the farrowing and weaner pen, and haptoglobin concentrations. Creep feed supplementation enhanced feed exploration at wk 2 post-weaning (0.29 ± 0.08 vs. 0.11 ± 0.03%, F (1, 27) = 5.27, P = 0.03), but did not affect other post-weaning behaviors. Pre-weaning creep feed provision and post-weaning creep feed supplementation did not affect overall feed intake, growth, feed efficiency and fecal consistency for the first 14 days post-weaning, neither body weight at d14 post-weaning. Nevertheless, CF-piglets had a lower within-pen coefficient of variation in body weight at d14 post-weaning than NF-piglets (13.6 ± 1.9 vs. 15.1 ± 1.5%, F (1, 26) = 6.89, P = 0.01). In conclusion, pre-weaning creep feed provision and post-weaning creep feed supplementation had no clear effects on piglet behavior and performance.

Effects of Early and Current Environmental Enrichment on Behavior and Growth in Pigs.

Enriched environments are known to beneficially affect the behavior of pigs, as compared with barren pens. The influence of enrichment may, however, depend on pigs' early life housing experiences. The aim of this study was to investigate the long-term effects of early and later life environmental enrichment on behavior and growth in pigs with different coping styles. Pigs were housed in either barren pens or in larger pens enriched with rooting substrates from birth, and half of them experienced a housing switch, i.e., a loss or gain of enrichment, at 7 weeks of age, creating four treatment groups. Home pen behavior and body weight were recorded until 19 weeks of age. Pigs were classified as reactive or proactive based on a backtest at 2 weeks of age. Enrichment increased time spent exploring, chewing, and play and decreased oral manipulation of penmates and pen-directed exploring and chewing. Behavior of pigs that switched from barren to enriched pens or vice versa reflected not only their actual environment, but also their early life housing. As early and later life enrichment affected most behaviors in opposite directions, effects of enrichment, or lack thereof, after the switch were more pronounced in pigs that had experienced a different early life condition. For instance, pigs experiencing an upgrade from barren to enriched pens seemed to "catch-up" by showing more exploration and play. Conversely, pigs exposed to a downgrade displayed more oral manipulation of penmates than ones kept barren throughout, which particularly held for pigs with a reactive coping style. Effects of early life and current housing on several other behaviors depended on coping style too. Pigs housed in enriched conditions appeared better able to cope with weaning than barren housed pigs, as they gained more weight and had higher feed intake post-weaning. Barren housed pigs had a lower body weight than enriched pigs just before the switch, after which growth was mainly determined by actual housing, with enriched kept pigs having a higher feed intake and body weight. Thus, not only current housing conditions, but also a (mis)match with the early life environment may affect behavior and growth of pigs.

Pigs Like It Varied; Feeding Behavior and Pre- and Post-weaning Performance of Piglets Exposed to Dietary Diversity and Feed Hidden in Substrate During Lactation.

Timely intake of solid feed is essential to ease the nutritional change from sow's milk to solid feed at weaning and thereby to reduce weaning-related problems. A significant percentage of piglets, however, do not or hardly consume solid feed before weaning. We studied effects of dietary variety and presenting the feed in substrate during lactation on the feeding behavior and performance of piglets up to 2 weeks post-weaning. Feed was provided ad libitum from d4 in two feeders, with four bowls each. In a 2 × 2 arrangement, 40 litters received either creep feed as a monotonous diet (MO) or four feed items simultaneously, i.e., creep feed, celery, cereal honey loops and peanuts, as a diverse diet (DD) and the feed was either provided without (CON) or with substrate (SUB), i.e., sand, in one of the two feeders up to weaning. Dietary diversity highly stimulated feed exploration and eating (≥2.5 times), feed intake and the percentage of (good) eaters from early in lactation, and enhanced piglet growth toward weaning (by 29 g/d), although MO-piglets spent more time eating creep feed from d18. Within MO, SUB-litters consisted of more good eaters than CON-litters. At weaning (d28) four piglets from the same treatment were grouped (n = 40 pens). DD-CON had the highest post-weaning feed intake and gain between d5-15 and the lowest proportion of pigs with higher tail damage scores. However, effects regarding behavior remained inconclusive, as DD-piglets had a lower and higher number of body lesions at 4 h and d15 post-weaning, respectively, spent less time exploring the feed(er) and drinker and environment, and more time nosing pen mates than MO-piglets. SUB-piglets showed a reduction in total post-weaning feed intake, gain (particularly between d0-2) and inactivity, increased levels of manipulation and aggression at week 1 and a higher number of body lesions at 4 h and d15 post-weaning. In conclusion, dietary diversity seems a promising feeding strategy in getting piglets to eat during lactation. Provision of substrate in the feeder subtly stimulated foraging behavior, but negatively impacted post-weaning adaptation, probably because treatments were not reinforced after weaning and piglets thus experienced loss of enrichment.

Feed intake of the sow and playful creep feeding of piglets influence piglet behaviour and performance before and after weaning.

Creep feed intake is variable and may be partly homeostatically and exploratory driven. We studied effects of maternal feed restriction and a 'play-feeder' on piglet behaviour and performance. 37 Litters received creep feed in a conventional (CON) or play-feeder (PL) and their sows were full-fed (FF) or restrictedly-fed (RES). Eaters were determined via rectal swabs. At weaning (d24) four piglets from the same treatment were grouped (n = 36 pens). RES hindered piglet growth by 41 g/d and enhanced time eating, creep feed intake and percentage of eaters at weaning versus FF. RES-PL had the largest proportion of moderate and good eaters. PL stimulated feeder exploration and attracted more piglets to the feeder than CON. Post-weaning, RES increased exploratory behaviours, feed intake between d0-5, and growth between d0-2, and reduced body lesions between d0-2 (within CON), drinking and ear biting. PL increased ingestive behaviours, feed intake and growth between d0-15, and BW at d15 post-weaning by 5%. PL also lowered the prevalence of watery diarrhoea, number of body lesions and piglets with ear (within FF) and tail (within RES) damage at d15 post-weaning. Treatments did not affect FCR. To conclude, RES and particularly PL (broader and for longer) result in less weaning-associated-problems.