Long-term dietary fatty acid intake is believed to induce changes in the human gut microbiome which might be associated with human health or obesity status; however, considerable debate remains regarding the most favorable ratios of fatty acids to optimize these processes. The objective of this sub-study of a double-blinded randomized crossover clinical study, the canola oil multi-center intervention trial, was to investigate effects of five different novel oil blends fed for 30 days each on the intestinal microbiota in 25 volunteers with risk of metabolic syndrome. The 60 g treatments included three MUFA-rich diets: (1) conventional canola oil (Canola); (2) DHA-enriched high oleic canola oil (CanolaDHA); (3) high oleic canola oil (CanolaOleic); and two PUFA-rich diets: (4) a blend of corn/safflower oil (25:75) (CornSaff); and (5) a blend of flax/safflower oil (60:40) (FlaxSaff). Stool samples were collected at the end of each period. DNA was extracted and amplified for 16S rRNA gene pyrosequencing. A total of 17 phyla and 187 genera were identified. While five novel oil treatments failed to alter bacterial phyla composition, obese participants resulted in a higher proportion of Firmicutes to Bacteroidetes than overweight or normal weight groups (P = 0.01). Similarly at the genus level, overall bacterial distribution was highly associated with subjects’ body mass index (BMI). Treatment effects were observed between MUFA- and PUFA-rich diets, with the three MUFA diets elevating Parabacteroides, Prevotella, Turicibacter, and Enterobacteriaceae’s populations, while the two PUFA-rich diets favored the higher abundance of Isobaculum. High MUFA content feedings also resulted in an increase of Parabacteroides and a decrease of Isobaculum in obese, but not overweight subjects. Data suggest that BMI is a predominant factor in characterization of human gut microbiota profile, and that MUFA-rich and PUFA-rich diets impact the composition of gut microbiota at lower taxonomical levels mainly in obese subjects.

Interactive effects between in-feed antibiotics (PC; 0.04% chlortetracycline + 0.004% Denagard) and a Saccharomyces cerevisiae fermentation product (XPC) were investigated. Five pens of 3 pigs/pen were randomly allotted to one of six diets consisting of control (NC; no additives), XPC alone (0.2%), PC alone, or PC plus one of three levels of XPC (0.1, 0.2, or 0.4%). On day 7, all pigs were bled for baseline serum and then orally inoculated with a 6-mL dose of 2 x 10(9) cfu/mL of ciprofloxacin-resistant Escherichia coli K88(+) (ETEC). Severity of diarrhea, using fecal score (FS), was assessed on days 8, 9, and 10. On day 10, pigs were bled and 1 pig/pen was killed to obtain gastrointestinal (GIT) samples. Remaining pigs were monitored for another 4 d and then killed to obtain GIT samples. Pigs fed PC and XPC in combination of PC had a lower (P = 0.02) FS than NC. The PC pigs had lower (P = 0.02) serum interleukin-6 and XPC pigs had higher (P < 0.01) serum tumor necrosis factor-α than NC pigs. Ileal mucosal ETEC count was lower on day 10 (P = 0.04) and day 14 (P < 0.01) when additives were fed in combination. Microbiome analysis of day 10 digesta using pyrosequencing showed that pigs fed the PC with XPC had enriched (P = 0.01) Streptococcaceae family than PC fed alone. On day 10, pigs fed PC alone and in combination with XPC at a lower dose had shallower (P = 0.01) crypt depth than those fed higher doses of XPC, XPC alone, or NC. Pigs fed XPC had a thicker colon wall on day 10 (P < 0.01) compared to those fed non-XPC diets. Ileal and colonic digesta NH(3) concentration was lower (P < 0.05) for pigs fed additives-containing diets on days 10 and 14. Feeding PC or XPC reduced diarrhea and the number of ETEC attached to the ileal mucosa; however, responses suggest independent and interactive effects that might be associated with the nature of these additives.

Khazanehei, H., Li, S., Khafipour, E. and Plaizier, J. C. 2015. Effects of dry period management on milk production, dry matter intake, and energy balance of dairy cows. Can. J. Anim. Sci. 95: 433–444. Effects of dry-period management on milk production, feed intake, and energy balance were determined in 11 second-parity (PAR 2) and 15 third or later parity (PAR 3+) cows. Cows were paired based on expected calving date, and randomly assigned to treatments including a conventional 60-d dry period with a 39-d far-off and a 21-d close-up diet (CONV), and a short 40-d dry period with only a close-up diet (SHORT). Treatment did not affect dry matter intake (DMI) and energy balance across the 6 wk before calving and the 4 wk after calving. Across the first 16 wk of lactation, cows on the short treatment had lower milk yield compared to cows on the CONU treatment that was mostly due to the lower production in PAR 3+ cows. Also, PAR 3+ cows on the SHORT treatment had lower milk protein yields and higher somatic cell counts than the other cows. In general, PAR 2 cows on the SHORT treatment had similar DMI, fat corrected milk yields, and protein and fat yields and percentages compared to cows in both parity groups on the CONV treatment. This suggests that the SHORT treatment may be suitable for PAR 2 cows, but not for older cows.

. 2015. Effects of dry period management and parity on rumen fermentation, blood metabolites, and liver triacylglyceride in dairy cows. Can. J. Anim. Sci. 95: 445Á453. The effects of dry period management on rumen fermentation, blood metabolites and liver triacylglyceride (TAG) were determined in 11 second-parity (PAR 2) and 15 third-parity and older (PAR 3') cows. Cows were paired and randomly assigned to two treatments: (1) DM) in a randomized block design. Concentrations of total volatile fatty acids, ammonia, and lactate in rumen fluid, and also concentrations of lactate, beta hydroxybutyric acid (BHBA), urea and insulin in plasma were not affected by treatment. Across the 3 wk after calving, cows on the SHORT treatment had higher blood non-esterified fatty acid (NEFA) and glucose, and at 1 wk after calving, these cows had a higher liver TAG than cows on the CONV treatment. Also, during this time, PAR 3' cows had higher serum NEFA compared with PAR 2 cows. Results suggest that the SHORT treatment resulted in more lipolysis, TAG accumulation in the liver and glucose sparing in early lactation compared with the CONV treatment, and that this effect was greater in PAR 3' cows than in PAR 2 cows.Key words: Dry period, dairy cows, blood metabolites, rumen fermentation, liver Khazanehei, H., Li, S., Khafipour, E. et Plaizier, J. C. 2015. Les effets de la gestion de la pe´riode de tarissement et de la pariteś ur la fermentation dans le rumen, les me´tabolites sanguins et le triacylglyce´ride du foie chez les vaches laitie`res. Can. J. Anim. Sci. 95: 445Á453. Les effets de la gestion de la pe´riode de tarissement sur la fermentation dans le rumen, les me´tabolites sanguins et le triacylglyce´ride (TAG) du foie ont e´te´de´termine´s chez 11 vaches de deuxie`me parite´(PAR 2) et 15 vaches de troisie`me parite´et plus (PAR 3'). Les vaches ont e´te´jumele´es puis assigne´es de fac¸on ale´atoire a`deux traitements: (1) une pe´riode de tarissement courte de 40 jours (SHORT Á « short 40-d dry period ») avec une die`te de pre´paration au veˆlage Les re´sultats sugge`rent que le traitement SHORT se solde par une augmentation de la lipolyse, une accumulation de TAG dans le foie et l'e´pargne du glucose dans les stades pre´coces de lactation par rapport au traitement CONV et cet effet e´tait plus grand chez les vaches PAR 3' que les vaches PAR 2.Mots clé s: Pe´riode de tarissement, vaches laitie`res, me´tabolites du sang, fermentation dans le rumen, foieThe transition period is a challenging phase for dairy cows in regard to metabolic and physiologic adaptations that cows undergo during this time. The high energy demand during early lactation commonly results in a negative energy balance, lipolysis, ketogenesis and fat accumulation in the liver, and, therefore, in reduced metabolic health (Weber et al. 2013). Dry period management affects metabolic health in early lactation (Janovick et al. 2011; van Knegsel et al. 2013). A short dry period between 28 and 35 d with only one diet may reduce the stresses of switching diets and i...

The effects of USFA treatments on gut microbiome profile were studied in 25 subjects (13 obese, 9 overweight, 3 normal) in a double‐blinded randomized crossover study consisting of five 30 d periods. Treatments included 60 g of canola oil (63% MUFA, 20% LA, 10% ALA), high oleic canola oil (72% MUFA, 15% LA, 2% ALA), high oleic canola/DHA oil (64% MUFA, 13% LA, 6% DHA), corn/safflower oil (18% MUFA, 69% LA) and flax/safflower oil (18% MUFA, 38% LA, 32% ALA). Stool samples were collected at the end of each period. DNA was extracted and amplified for pyrosequencing. Sequences were edited and taxonomically classified using mothur software and Silva database. Categorical data were analyzed using GLIMMIX of SAS and PLS‐DA of SIMCA. A total of 17 phyla and 195 genera were identified. The USFA treatments did not affect microbiome at the phylum level. However, obese participants had a higher proportion of Firmicutes to Bacteroidetes than overweight or normal groups (P<0.05). At the genus level, three MUFA diets increased Clostridiales, Parabacteroides, Prevotella, and Turicibacter's population. Anaerostipes, Coprobacillus, and Faecalibacterium population were greater in high oleic canola oil compared to that in high oleic canola/DHA oil. Data suggest that obesity was associated with the decline in Bacteroidetes while USFA consumption only affected the microbiome at the genus level.Grant Funding Source: ARDI