The effects of live yeast Saccharomyces cerevisiae (strain CNCM I-4407, 10(10) cfu/g; Actisaf; Lesaffre Feed Additives, Marcq-en-Baroeul, France) on the severity of diarrhea, immune response, and growth performance in weaned piglets orally challenged with enterotoxigenic Escherichia coli (ETEC) strain O149:K88 were investigated. Live yeast was fed to sows and their piglets in the late gestation, suckling, and postweaning periods. Sows were fed a basal diet without (Control; n = 2) or with (Supplemented; n = 2) 1 g/kg of live yeast from d 94 of gestation and during lactation until weaning of the piglets (d 28). Suckling piglets of the supplemented sows were orally treated with 1 g of live yeast in porridge carrier 3 times a week until weaning. Weaned piglets were fed a basal starter diet without (Control; n = 19) or with (Supplemented; n = 15) 5 g of live yeast/kg feed for 2 wk. Significantly lower daily diarrhea scores (P < 0.05), duration of diarrhea (P < 0.01), and shedding of pathogenic ETEC bacteria (P < 0.05) in feces was detected in the supplemented piglets. Administration of live yeast significantly increased (P < 0.05) IgA levels in the serum of piglets. Evidence indicates that decreased infection-related stress and severity of diarrhea in yeast-fed weaned piglets positively affected their growth capacity in the postweaning period (P < 0.05). The results suggest that dietary supplementation with live yeast S. cerevisiae to sows and piglets in the late gestation, suckling, and postweaning periods can be useful in the reduction of the duration and severity of postweaning diarrhea caused by ETEC.

The effects of live yeast (strain CNCM I-4407; Actisaf Sc 47; Phileo Lesaffre Animal Care, Marcq-en-Baroeul, France) administration on nutrient digestibility and fecal microflora in dogs were investigated. The study included 24 young beagle dogs. They were allocated in control and live yeast (LY) groups (6 males and 6 females in each). During the Adaptation (d 1 to 28) and Trial (d 29 to 70) periods, the dogs received a standard dry pelleted diet. In the Trial period, the LY dogs were given capsuled Actisaf Sc 47 at 1 g/kg live weight with at 2.9 × 10 cfu/g. The control dogs received empty capsules. Live weight and feed consumption were recorded. Blood samples for complete blood count (CBC) and serum biochemistry (urea, creatinine, alkaline phosphatase, and alanine aminotransferase) and fecal samples for pH, microbiology, DM, lactic acid, and ammonia and digestibility evaluation were collected during the Trial period from each dog. The LY dogs had a higher ( < 0.05) weight gain during the Trial period than the control ones. Feed consumption was not adversely affected by LY. The CBC values and urea, creatinine, alkaline phosphatase, and alanine aminotransferase were not adversely affected by LY. Live yeast did not significantly influence pH of fresh feces. Fecal lactic acid and ammonia concentrations were not affected. The LY dogs showed lower ( < 0.05) Escherichia coli and fecal enterococci counts in feces than the control ones. Lactic acid bacteria, Clostridium perfringens, and total coliforms did not show any significant differences between the treatments. The LY dogs showed a higher ( < 0.05) apparent digestibility of NDF. Digestibilities of DM, ash, crude fiber, CP, and fat were not influenced.

The study evaluated dietary supplementation with live yeast (LY) Saccharomyces cerevisiae (CNCM I‐4407, 1010 CFU/g, Actisaf; Phileo Lesaffre Animal Care, France) on rumen fermentation and serum metabolic profile in lactating dairy cows. Fifty Holstein cows received a total mixed ration with (Live Yeast Diet, LYD, n = 25) or without (Control Diet, CD, n = 25) 5 × 1010 CFU/cow/day of LY from 3 to 19 weeks of lactation. Rumen fermentation and serum metabolic profile were measured in eight cows per treatment at 3, 7, 11, 15, 19 weeks post‐partum. LYD showed an increased daily milk yield (+4%) over CD (p < 0.05). Mean rumen pH at 4 hr after morning meal was higher in LYD (6.59) than CD (6.32) (p < 0.01). Total volatile fatty acids (VFA) and acetate molar proportion were higher in LYD (114.24 mM; 25.04%) than CD (106.47 mM; 24.73%) (p < 0.05). Propionate and butyrate molar proportions, acetate to propionate ratio, ammonia levels did not differ between LYD and CD. Ruminal lactate was lower in LYD than CD (9.3 vs. 16.4 mM) (p < 0.001), with a 53% decrease in LYD. During peak lactation, LYD had lower serum NEFA (p < 0.05, 0.40 vs. 0.48 mM) and BHBA (p < 0.01, 0.47 vs. 0.58 mM) than CD, lower liver enzyme activities (AST 1.39 vs. 1.54 ukat/L) (p < 0.05). Serum glucose was higher in LYD at peak lactation (3.22 vs. 3.12 mM, and 3.32 vs. 3.16 mM respectively) (p < 0.05). The results confirmed a reducing effect of LY on lactate accumulation in rumen fluid, associated with an increase in rumen pH. Lower serum levels of lipomobilization markers, liver enzyme activities and higher glucose levels may suggest that live yeast slightly mitigated negative energy balance and had a certain liver protective effect.

An experiment was carried out on four dry Holstein cows fitted with rumen cannulas that were divided into two groups. The crossover design experiment was divided into 4 periods of 3 weeks. Each period consisted of a 17-day preliminary period followed by a 4-day experimental period. Cows were fed twice daily the total mixed ration based on maize silage and concentrate. Control cows (Control) received the basal diets while experimental animals (Yeast) received the basal diet supplemented with 3.0 g of live yeast (BIOSAF Sc 47, Lesaffre, France) at each feeding. During each experimental period ruminal pH and redox potential (Eh) were monitored continuously using a developed wireless probe. Further, in each experimental period five samples of ruminal fluid were taken at 6:30, 8:30, 10:30, 13:30 and 16:30 h to determine the content of volatile fatty acids, lactic acids and ammonia. On the last day of each period, blood samples were taken for determination of blood parameters and acid-base balance. Average daily dry matter intake throughout the experiment was 8.2 kg/day and was not affected by the treatment. The average ruminal pH in Control was 6.16 that was significantly lower than in Yeast, being 6.26 (P < 0.001). The diurnal pattern of ruminal pH showed a similar trend in both groups. Mean Eh in Control (-210 mV) differed significantly from Yeast (-223 mV, P < 0.001). The mean value of rH (Clark's Exponent) calculated for Control (5.33) was higher than that calculated for Yeast (5.09, P < 0.001). Total VFA concentrations were on average 40.8mM in Control and 57.2mM in Yeast (P > 0.05). Lactate and ammonia concentrations at individual sampling times and overall mean did not differ significantly between treatments (P > 0.05). Blood pH and CO 2 were not affected by the treatment.

The aim of this study was to validate selected precision livestock farming (PLF) methods of nutrition and feeding management of high-yielding Holstein dairy cows. In a feeding trial with 36 dairy cows, the effect of replacing 0.1 kg of sodium bicarbonate in the control total mixed ration (TMR-C) with 1 kg of wheat straw in the experimental total mixed ration (TMR-S) on the physiological status of cows and the amount of milk produced (milk yield, MY) was investigated. Feed intake time (FT), as measured using tensometric feed troughs (TFT), was significantly longer with TMR-S (188 min) than with TMR-C (157 min). Differences between TMR-C and TMR-S were not significant for FT or rumination time (RT), as measured by a sensor in the collar (VSC). There was only a weak correlation between the two technologies (TFT vs. VSC) for FT (r = 0.27). Differences between TMR-C and TMR-S were not significant for values measured in rumen fluid (pH, acid and ammonia levels) nor for values measured by sensors in the milking parlour (MY, fat and protein percentage of milk). Milk analysis in the laboratory showed that the cows fed TMR-C had higher urea (26.6 vs. 22.7 mg/100 ml) and free fatty acid (0.87 vs. 0.33 mmol/100 g) levels in milk. Moderate correlations were between TMR intake and MY (r = 0.55); between MY and milk fat (r = -0.46); between milk fat and milk protein (r = 0.63); and between milk fat and milk protein measured by sensors and in the laboratory (r = 0.47 and r = 0.42, respectively). In view of the above results, further research and data validation for each technology are needed.