The use of medicinal zinc oxide (ZnO) in post-weaning diets must be phased out in the European Union by 2022, resulting in urgent needs for alternative strategies to prevent diarrhea in pigs. The objective of this study was to test the effect of four different dietary protein strategies with different amino acid profiles on diarrhea frequency and pig performance as alternative diet plans when medicinal ZnO waswill be excluded from the diet. A total of 6 800 Duroc x (Danish Landrace x Yorkshire) pigs, weaned around 28 days of age, were randomly assigned by sex and size to six dietary treatments. The treatments were; standard CP levels (191, 184, 184 g/kg CP) and allocated 2 500 ppm ZnO in phase 1 (PC = positive control), standard CP levels (191, 184, 184 g/kg CP) and no added ZnO in phase 1 (NC = negative control), CP levels of 166, 184, 184 g/kg (LSS = low-standard-standard), CP levels of 166, 162, 192 g/kg (LLH = low-low-high), CP levels of 140, 193, 192 g/kg (VHH = very low-high-high), and lastly 140, 174, 192 g/kg CP levels (VMH = very low-medium-high). The pigs entered the trial at ~7 kg BW and exited at ~30 kg BW. As expected, the PC treatment resulted in 42% fewer diarrhea pen treatments in the total trial period compared to the NC group (P < 0.05), whereas both PC and LLH had fewer diarrhea treatment days per pig compared to NC pigs (P < 0.05). Additionally, at the point of treatment, the NC pens had 33% fecal floor samples positive for pathogens, compared to 80% samples positive for pathogens in the PC pens. This suggests that ZnO has a particular positive effect on non-infectious diarrhea without bacterial involvement. A reduction in dietary CP levels in phase 1 led to a reduced average daily gain (ADG) in LLH and VMH pigs and a poorer feed conversion ratio (FCR) in VHH pigs during the overall study period compared to the NC pigs (P < 0.05). Conclusively, a diet with low CP levels from weaning to about 15 kg BW had a reducing effect on diarrhea, but decreased ADG without affecting the FCR.

Background: Antibiotic (AB) consumption in production animals has a high awareness among politicians and consumers due to the risk of selection for AB resistance among potentially zoonotic bacteria. However, AB treatment of animals is at times necessary to treat diseases and ensure the wellbeing of the animals we take into our care. Raised without antibiotics (RWA) is a concept where pigs are individually ear-tagged for tracking, and if pigs are AB treated, they lose their RWA status. At slaughter, the farmer receives an additional price for non-AB treated pigs. The objective of this study was to identify risk factors for AB treatment and to investigate growth performance of pigs in two Danish RWA herds.Results: A total of 518 pigs in herd A and 436 pigs in herd B, were individually ear-tagged and subjected to weekly investigations of AB treatment status from birth to 12 weeks of age. Bodyweight was recorded at birth, 2, 4 and 12 weeks of age. The results showed, that at 12 weeks of age, 82 of 518 liveborn pigs were AB treated in herd A and 31 of 436 liveborn pigs were AB treated in herd B. Individual pigs that required AB treatment had a reduced average daily gain from day 0 to 28 in both herds (herd A,P < 0.001; herd B,P = 0.062) and from day 0 to 84 in herd A (P < 0.001). Additionally, significant risk factors for AB treatment were identified as a low bodyweight in herd A, whereas barrows and litters with less than 19 piglets were the main risk factors in herd B.Conclusion: The results suggests that in order to reduce AB treatments particular attention should be addressed to smaller pigs and barrows in RWA herds. In these two Danish RWA herds from this study it was possible for 64 and 68% pigs to reach 12 weeks of life without any AB treatments.

Soy protein concentrate improves nutrient utilization and growth performance compared to soybean meal, and diets with a low crude protein (CP) level decreases diarrhoea. The objectives were to (1) test a low CP diet based on different soy products, and (2) to test a very-low CP diet (15.1%) with amino acids (AA) on diarrhoea and productivity. A total of 5,635 weaned pigs (~28 days), were assigned to five dietary treatments; PC (positive control): Standard CP levels (192, 189, 191 g/kg CP) with 2500 ppm ZnO; NC (negative control): Same as PC without ZnO; SP (Soy protein concentrate): Low CP levels (176, 174, 191 g/kg CP); SB (Soybean meal): Low CP levels (177, 176, 191 g/kg CP); and XLA (X-low CP + AA): Very low CP levels (154, 151, 191 g/kg CP) with AA. The PC and XLA diets reduced diarrhoea by 41 and 61%, respectively, compared to the NC group, while no difference between SB and SP were observed. The XLA diet reduced feed intake and daily gain compared with PC and NC, where SP, SB, and XLA had a poorer feed conversion compared with PC. Conclusively, the SP and SB low-protein diets did not reduce diarrhoea or growth performance, whereas the XLA diet decreased both diarrhoea and performance.

Selection for increased litter sizes have decreased the average birth weight of piglets and up to 30% of newborn piglets in Danish herds show signs of intrauterine growth restriction (IUGR). It has been reported that around 48% of liveborn piglets dying between birth and weaning have empty stomachs, and that IUGR piglets do not ingest the recommended amount of colostrum to survive. The aim of this study was to investigate how much colostrum could be administrated depending on whether they were IUGR compared to normal piglets. Seventy-two piglets within 24 h of farrowing were classified as either IUGR or normal based on their head morphology. Stomach weight, length and capacity were measured along with bodyweight (BW). The results displayed a decreased BW, empty stomach weight and capacity in IUGR piglets, as well as a decreased relative stomach capacity in IUGR compared with normal piglets. In conclusion, birth weight is not the only factor influencing stomach capacity, and IUGR piglets have a smaller stomach capacity compared with normal piglets. It is estimated that IUGR piglets have the capacity to be given a bolus of 25 mL per kg/BW, whereas a normal piglet have a higher capacity (30 mL per kg/BW).

The use of medicinal zinc oxide (ZnO) to prevent diarrhoea post-weaning will be banned in the EU from 2022. Therefore, new alternatives are needed to avoid an increase in diarrhoea and higher antibiotic use. A low dietary CP level has shown to lower the frequency of diarrhoea in pigs, due to lower microbial protein fermentation in the colon as well as improved conditions in the small intestine after weaning. The objective of this study was to examine the effect of decreased CP levels post-weaning as an alternative to medicinal ZnO on gut morphology and histopathology. Five hundred and sixty pigs were randomly assigned into one of six groups receiving a two-phase diet from 5.5 to 15 kg: positive control group (PC) with medicinal ZnO and standard levels of protein (19.1-18.4% CP), negative control group (NC) without medicinal ZnO and standard levels of protein (19.1-18.4% CP). The remaining four low protein groups were a low-standard (LS) CP level (16.6-18.4% CP), a low-low (LL) CP level (16.6-16.2% CP), a very low-high (VLH) CP level (14-19.3% CP) and a very low-medium (VLM) CP level (14-17.4% CP). Individual BW was recorded at day 0, 10 and 24 post-weaning, and all antibiotic treatments were recorded. Tissue samples from the small intestine (mid-jejunum) for morphological and histopathologic analysis, organ weights, blood and urine samples were collected at day 10 and 24 post-weaning from a total of 90 sacrificed weaners. The results demonstrated no differences in intestinal morphology between groups, but the histopathology showed a damaged brush border score in VLM and VLH pigs . In addition, a lower blood urea nitrogen in VLM pigs at 24 days was found. The LL and VLM pigs had a significantly decreased average daily gain in the overall trial period compared to PC and NC pigs. Conclusively, intestinal brush border was damaged by the very low protein diet at 24 days post-weaning, but intestinal morphology was unaffected by dietary strategy.

A well-balanced gut microbiome is associated with improved health outcomes, but to date, the GM of IUGR piglets have only been sparsely investigated. Here, we investigated GM composition, color of colon content, and blood parameters of 20 IUGR and 20 normal 24-day-old piglets. No significant differences were detected in colon microbiota composition between IUGR and the normal piglets with respect to alpha and beta diversity measures. The colon content of these piglets displayed three colors: brown, black, and yellow. Interestingly, the color of the colon content varied with microbial community composition, with significant differences in the relative abundance of taxa belonging to Fusobacteria and Treponema. Fusobacteria were most abundant in yellow fecal samples, with a mean relative abundance around 5.6%, whereas this was 0.51% within brown and 0.02% for the black fecal samples. Fusobacteria positively correlated with total blood protein, albumin, and triglycerides. Contrarily, Treponema was at 0.9% the most abundant in black fecal samples, while present at 0.1% of relative abundance in brown fecal samples and 0.01% in yellow samples, correlating positively with blood iron content. This study indicates that colon/fecal content color can be used as indicator for specific GM and metabolite signatures.