The performance of piglets in nurseries may vary depending on body weight, age at weaning, management, and pathogenic load in the pig facilities. The early events in a pig’s life are very important and may have long lasting consequences, since growth lag involves a significant cost to the system due to reduced market weights and increased barn occupancy. The present review evidences that there are several strategies that can be used to improve the performance and welfare of pigs at weaning. A complex set of early management and dietary strategies have been explored in sows and suckling piglets for achieving optimum and efficient growth of piglets after weaning. The management strategies studied to improve development and animal welfare include: (1) improving sow housing during gestation, (2) reducing pain during farrowing, (3) facilitating an early and sufficient colostrum intake, (4) promoting an early social interaction between litters, and (5) providing complementary feed during lactation. Dietary strategies for sows and suckling piglets aim to: (1) enhance fetal growth (arginine, folate, betaine, vitamin B₁₂, carnitine, chromium, and zinc), (2) increase colostrum and milk production (DL-methionine, DL-2-hydroxy-4-methylthiobutanoic acid, arginine, L-carnitine, tryptophan, valine, vitamin E, and phytogenic actives), (3) modulate sows’ oxidative and inflammation status (polyunsaturated fatty acids, vitamin E, selenium, phytogenic actives, and spray dried plasma), (4) allow early microbial colonization (probiotics), or (5) supply conditionally essential nutrients (nucleotides, glutamate, glutamine, threonine, and tryptophan).

Feed additives have been suggested to improve animal growth performance through modulating the gut microbiota. The hypothesis of this study was that the combination of two organic acids would exert synergistic effects on the growth performance and gut microbiota of weaning pigs. To test this hypothesis, we followed 398 weaning pigs from two university experiment stations (University of Illinois at Urbana-Champaign (UIUC) and University of Arkansas (UA)) to determine the effects of increasing levels (0%, 0.035%, 0.070%, and 0.105%) of sodium butyrate combined with 0.5% benzoic acid on the growth performance of nursery pigs. At the UA, an additional negative control diet was included and the gut microbiota analysis was carried out. At both universities, increasing levels of sodium butyrate in a diet containing 0.5% benzoic acid improved growth performance, which reached a plateau in the pigs fed 0.035% (SBA0.035) or 0.070% (SBA0.070) butyrate. Gut microbiota analysis revealed that pigs fed the SBA0.035 diet had more diverse microbiota and contained more potentially beneficial bacteria such as Oscillospira, Blautia, and Turicibacter and reduced levels of Veillonella and Sarcina. Results of the present study indicated that the inclusion of sodium butyrate at moderate levels in a diet containing 0.5% benzoic acid improved growth performance of weaning pigs and established potential health benefits on gut microbiota.

The early exposure of the fetus to certain volatiles may result in a further preference for these compounds later in life and could positively affect the acceptance of feed containing a similar flavor and the zootechnical responses. The study consisted of 2 trials to determine if including Fluidarom 1003 (a commercially flavored feed additive containing >25% anethol and cinnamaldehyde and >10% eugenol; Norel S.A., Madrid, Spain, Spain) in sow and postweaning piglet diets 1) provokes the presence or absence of 3 major volatile compounds (anethol, cinnamaldehyde, and eugenol) in amniotic fluid and milk, affecting piglet performance (BW, ADG, ADFI, and feed conversion ratio) after weaning, and 2) modifies creep feed consumption and feed preference in a 2-choice test. The major compounds, anethol, cinnamaldehyde, and eugenol, were detected in amniotic fluid; however, only traces were observed in milk. The inclusion of flavor in the sow diets improved piglet consumption and growth after weaning (P = 0.001). Furthermore, the positive reward associated with the flavor included in the sow diet was stronger when piglets were offered a nonflavored creep feed (P < 0.05). Therefore, early exposure of pigs’ fetuses to maternal dietary clues at the end of gestation might allow for conditioning pigs after weaning. Copyright © 2016. American Society of Animal Science .

An experiment was conducted to determine the effects of two sources of copper (Cu) from copper sulfate (CuSO₄) and dicopper oxide (Cu₂O, CoRouge) at three levels of inclusion (15, 75, and 150 mg/kg) on growth performance and gut microbiota of broilers. A total of 840 one-d-old male chickens (Ross 308) were weighed and randomly allocated to seven dietary treatments: negative control (NC, a basal diet without Cu addition), and the NC supplemented with 15, 75, or 150 mg Cu/kg from CuSO₄ or Cu₂O (12 replicate pens/treatment, 10 chicks per pen). Broilers were challenged by reusing an old litter with high concentrations in Clostridium perfringens to promote necrotic enteritis. Broiler performance was registered at d 21, 35, and 42. Excreta samples were collected at d 14, 28, and 42 for antimicrobial resistance (AMR) analyses. At d 43, one broiler per pen was euthanized to obtain ileal content for microbial characterization. Body weight d 35 and daily gain d 42 improved (P < 0.05) in Cu₂O as Cu dose inclusion increased from 15 mg/kg to 150 mg/kg. Supplementation of 150 mg/kg of Cu from Cu₂O decreased the abundance (P < 0.01) of some families such as Streptococcaceae and Corynebacteriaceae and increased the abundance (P < 0.05) of some commensal bacteria like Clostridiaceae and Peptostreptococcaceae. Phenotypic AMR was not different among treatments on d 14 and 28. Isolated Enterococcus spp. from broilers fed the NC diet on d 42 showed higher (P < 0.05) resistance to enrofloxacin, gentamicin, and chloramphenicol compared with Cu treatments. By contrast, the isolated Escherichia coli from broilers fed 150 mg/kg of Cu, either from CuSO₄ or Cu₂O, showed higher (P < 0.05) resistance to streptomycin and chloramphenicol compared to the NC. This study suggests that supplementing 150 mg/kg of Cu from Cu₂O establishes changes in the gut microbiota by regulating the bacterial population in the ileum, which may explain the positive impact on broilers' growth performance.

The beneficial effect of elevated concentrations of copper (Cu) on growth performance of pigs has been already demonstrated; however, their mechanism of action is not fully discovered. The objective of the present experiment was to investigate the effects of including Cu from copper sulfate (CuSO₄) or monovalent copper oxide (Cu₂O) in the diet of growing pigs on oxidative stress, inflammation, gene abundance, and microbial modulation. We used 120 pigs with initial body weight (BW) of 11.5 ± 0.98 kg in 2 blocks of 60 pigs, 3 dietary treatments, 5 pigs per pen, and 4 replicate pens per treatment within each block for a total of 8 pens per treatment. Dietary treatments included the negative control (NC) diet containing 20 mg Cu/kg and 2 diets in which 250 mg Cu/kg from CuSO₄ or Cu₂O was added to the NC. On day 28, serum samples were collected from one pig per pen and this pig was then euthanized to obtain liver samples for the analysis of oxidative stress markers (Cu/Zn superoxide dismutase, glutathione peroxidase, and malondialdehyde, MDA). Serum samples were analyzed for cytokines. Jejunum tissue and colon content were collected and used for transcriptomic analyses and microbial characterization, respectively. Results indicated that there were greater (P < 0.05) MDA levels in the liver of pigs fed the diet with 250 mg/kg CuSO₄ than in pigs fed the other diets. The serum concentration of tumor necrosis factor-alpha was greater (P < 0.05) in pigs fed diets containing CuSO₄ compared with pigs fed the NC diet or the diet with 250 mg Cu/kg from Cu₂O. Pigs fed diets containing CuSO₄ or Cu₂O had a greater (P < 0.05) abundance of genes related to the intestinal barrier function and nutrient transport, but a lower (P < 0.05) abundance of pro-inflammatory genes compared with pigs fed the NC diet. Supplementing diets with CuSO₄ or Cu₂O also increased (P < 0.05) the abundance of Lachnospiraceae and Peptostreptococcaceae families and reduced (P < 0.05) the abundance of the Rikenellaceae family, Campylobacter, and Streptococcus genera in the colon of pigs. In conclusion, adding 250 mg/kg of Cu from CuSO₄ or Cu₂O regulates genes abundance in charge of the immune system and growth, and promotes changes in the intestinal microbiota; however, Cu₂O induces less systemic oxidation and inflammation compared with CuSO₄. Copper is a nonrenewable mineral resource that is essential for all biological organisms. After banning the antibiotics, copper has received considerable attention due to its antimicrobial properties that improve performance in animals when fed over the minimum requirement. The present study evaluated two sources of Cu (copper sulfate and monovalent copper oxide) compared with a nonsupplemented diet and the likely mechanism of action which leads to improved pig performance. Pigs fed high concentrations of copper sulfate showed increased liver oxidation and inflammatory indicators in the blood. Elevated concentrations of Cu improved intestinal epithelial barrier function, modulation of inflammatory responses, increased beneficial microbes, and reduced pathogens in the gut. Therefore, supplementation of high levels of Cu appears to be effective in promoting pig growth, but therapeutic doses of Cu sulfate increase the inflammatory response.

Two experiments were conducted to test the hypothesis that a corn-expressed phytase increases growth performance, bone measurements, and nutrient digestibility by young growing pigs, if added to diets that are deficient in Ca and P. In Exp. 1, 60 pigs (initial BW: 10.78 ± 0.67 kg) were randomly allotted to 6 dietary treatments that included a positive control diet (PC; 0.70% total Ca and 0.60% total P) and a negative control diet (NC; 0.50% total Ca and 0.42% total P). Four additional diets were formulated by supplementing the NC diet with 250, 500, 1,000, or 1,500 phytase units (FTU)/kg. Diets were fed for 28 d and the individual BW of pigs on days 1 and 28 were recorded. Fecal samples were collected from days 25 to 27 to calculate apparent total tract digestibility (ATTD) of Ca and P. On the last day of the experiment, all pigs were euthanized, and the left femur was removed and analyzed for ash, Ca, and P. Results indicated that growth performance, ATTD of Ca and P, and bone ash measurements were reduced (P < 0.05) in NC fed pigs compared with PC fed pigs. However, growth performance, ATTD of Ca and P, and bone ash measurements were improved (linear and quadratic, P < 0.05) by including increasing concentrations of phytase to the NC diet. In Exp. 2, experimental procedures were similar to those used in Exp. 1. Forty-eight pigs (initial BW: 11.15 ± 0.85 kg) were randomly allotted to 6 dietary treatments in a 28-d experiment. Treatments included a PC diet, an NC diet, and 4 diets in which 500 or 1,000 FTU/kg of either the corn-expressed phytase or a commercial microbial phytase were added to the NC diet. Pigs fed the NC diet had reduced (P < 0.01) final BW, ADG, G:F, and bone ash concentrations compared with pigs fed the PC diet. When 500 FTU/kg phytase was fed, no differences were observed in growth performance or bone ash measurements between phytase sources, and there were no differences in growth performance among pigs fed 1,000 FTU/kg of either phytase source or the PC diet. However, regardless of concentration or source of phytase, pigs fed the PC diet had greater (P < 0.001) amount of bone ash, bone Ca, and bone P compared with pigs fed phytase diets. In conclusion, the corn-expressed phytase is effective in improving growth performance, Ca and P digestibility, and bone measurements in pigs fed diets that are deficient in Ca and P.