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This study evaluated the effects of novel silage inoculants containing lactic acid bacteria (LAB) and fibrolytic enzymes on ensiling, aerobic stability (AS), and the performance of growing beef cattle. Whole-plant corn forage was either uninoculated (CON) or inoculated with a mixture of LAB containing (cfu g−1 fresh forage) 1.5 × 105L. hilgardii (CNCM I-4785), 1.5 × 105L. buchneri (NCIMB 40788) and 1.0 × 105P. pentosaceus (NCIMB 12455) for a total of 4.0 × 105 cfu g−1 fresh forage LAB (IB), or a combination of IB plus fibrolytic enzymes (xylanase + β-glucanase) (IC). All treatments were ensiled in mini-silos, whereas CON and IC were also ensiled in silo bags for the growth performance study. Total bacteria (TB) counts were lower (P = 0.02) for IC than CON after 14 d of ensiling, whereas TB counts of IC and IB were greater (P ≤ 0.01) than CON after 60 d of ensiling in mini-silos. The LAB in IC and IB ensiled in mini-silos were greater than CON on d 60 (P ≤ 0.01) and 90 (P ≤ 0.001) of ensiling and after 3 d (P ≤ 0.01) of aerobic exposure (AE). Silage pH of IC ensiled in silo bags was lower than CON on d 3 (P < 0.01), 7 (P < 0.001), and 14 (P = 0.02) of AE. Yeast counts were lower for IC than CON in terminal silage (P < 0.001), and after 3 (P < 0.001) and 7 d (P < 0.01) of AE. Acetate (AC) concentrations were higher (P ≤ 0.02) for IC than CON throughout AE, whereas lactate (LA) concentrations of IC were greater than CON on d 3 (P < 0.001), 7 (P < 0.01), and 14 (P < 0.001) of AE. Greater AC concentration and lower yeast counts resulted in greater (P < 0.001) stability for IC ensiled in silo bags than CON after 14 d of AE. Growth performance of steers was similar (P > 0.05) as the nutrient composition of silage was similar across diets. Improved AS of IC could potentially have a greater impact on DMI, production efficiency, and growth performance in large-scale commercial feedlot operations where silage at the silo face may be exposed to air for longer periods of time.

The aim of this study was to assess the effect that feeding

A total of 150 21-day-old weaned piglets [(Yorkshire × Landrace) × Duroc] were randomly assigned to 3 groups based on average initial body weight (6.96 ± 0.21 kg) to evaluate the effects of dietary supplementation of probiotic, paraprobiotic, and hydrolyzed yeast mixture (PPY) on growth performance, nutrient digestibility, fecal bacteria counts, fecal calprotectin contents, and diarrhea rate in a 42-day experiment (phase 1: days 1-14; phase 2: days 15-42). There were 10 replicate pens per treatment with 5 pigs per pen (three gilts and two barrows). The experimental diets were a basal diet, without additive (CON), a basal diet supplemented with pharmacological levels of zinc oxide (ZnO; TRT1), and an experimental treatment including PPY (TRT2). Pigs in TRT1 were provided with a basal diet + 3000 mg/kg (as fed) ZnO during phase 1, and a basal diet during phase 2. Pigs in TRT2 were provided with a basal diet + 200 mg/kg (as fed) probiotic for a final concentration of 2 × 109 colony forming units (CFU)/kg diet + 800 mg/kg (as fed) paraprobiotic + 10 g/kg (as fed) hydrolyzed yeast mixture during phase 1, and a basal diet +100 mg/kg (as fed) probiotic + 400 mg/kg (as fed) paraprobiotic mixture during phase 2. Pigs in TRT1 and TRT2 tended to be heavier at day 14 and were significantly heavier at day 42 than CON pigs. Growth rate during days 1-14, 15-42, and 1-42 was similarly affected by treatment while feed efficiency was unaffected by treatment in the first 14 days but was significantly higher for TRT 1 pigs between 15-42 and 1-42 days with TRT2 being intermediate. Apparent nitrogen and energy digestibility were both significantly higher for pigs on TRT1 and TRT2 compared with the CON. There were no significant differences in any parameters measured between TRT1 and TRT2. Therefore, we demonstrated that PPY supplementation had comparable effects as ZnO on nutrient digestibility and the performance of weaned piglets.

Two separate experiments were conducted to compare the nutrient digestion and growth performance of beef cattle fed diets containing up to 77% of two conserved alfalfa hays. The two alfalfa hays were baled either at the optimum moisture (8.6%) or at a higher-than optimum moisture (21.4%) with application of a mixture of Pediococcus pentosaceus and chitinase at baling. Digestibility of dry matter, neutral detergent fibre, acid detergent fibre, rumen parameters, and growth performance were similar (P ≥ 0.16) for cattle fed either diet. A combination of P. pentosaceus and chitinase has the potential to preserve high-moisture alfalfa hay.

Perturbations in early life gut microbiota can have long-term impacts on host health. In this study, we investigated antimicrobial-induced temporal changes in diversity, stability, and compositions of gut microbiota in neonatal veal calves, with the objective of identifying microbial markers that predict diarrhea. A total of 220 samples from 63 calves in first 8 weeks of life were used in this study. The results suggest that increase in diversity and stability of gut microbiota over time was a feature of “healthy” (non-diarrheic) calves during early life. Therapeutic antimicrobials delayed the temporal development of diversity and taxa–function robustness (a measure of microbial stability). In addition, predicted genes associated with beta lactam and cationic antimicrobial peptide resistance were more abundant in gut microbiota of calves treated with therapeutic antimicrobials. Random forest machine learning algorithm revealed that Trueperella, Streptococcus, Dorea, uncultured Lachnospiraceae, Ruminococcus 2, and Erysipelatoclostridium may be key microbial markers that can differentiate “healthy” and “unhealthy” (diarrheic) gut microbiota, as they predicted early life diarrhea with an accuracy of 84.3%. Our findings suggest that diarrhea in veal calves may be predicted by the shift in early life gut microbiota, which may provide an opportunity for early intervention (e.g., prebiotics or probiotics) to improve calf health with reduced usage of antimicrobials.

Objective The objective of this study was to evaluate the efficacy of Saccharomyces cerevisiae boulardii CNCM I-1079 (SCB; Lallemand Animal Nutrition, Milwaukee, WI) in improving growth and fecal consistency in young dairy calves. Materials and Methods Male Holstein calves that arrived at a commercial rearing facility were randomly assigned to 1 of 3 treatment groups: control (no active dry yeast supplement); 5.0 g per head per day of ProTernative Milk containing 10 × 109 cfu of SCB (SCB5); or 10.0 g per head per day of ProTernative Milk containing 20 × 109 cfu of SCB (SCB10). These treatments were administered in the daily allotment of milk replacer. Fecal scores, bovine respiratory disease scores, and treatments administered were recorded on a daily basis. Body weight was measured at arrival and d 42 and 56 following arrival. Results and Discussion A total of 240 male Holstein calves were enrolled in the trial, with 80 calves in each respective treatment group. No differences among the groups were found with respect to mortality, fecal scores, or bovine respiratory disease scores. A growth advantage was found, especially in the postweaning period, with the SCB10 group having a 0.17 kg/d increase in ADG from d 42 to 56 after arrival when compared with the control. No difference in growth, however, was observed in the group fed SCB5. Implications and Applications This study demonstrates that supplementation of SCB before weaning is associated with a growth advantage, despite almost 30 and 7% of the calves experiencing diarrhea and pneumonia, respectively.

This study aimed to evaluate the effect of probiotic (Saccharomyces cerevisiae boulardii CNCM I-1079) supplementation during feedlot adaptation period on performance of Nellore bulls. One-hundred ninety-eight Nellore bulls were used in a completely randomized block design, divided in 22 pens (9 animals/pen). Treatments were: CON – adaptation diet and finishing diet comprised of basal diet (with 28 ppm of monensin); and SCB – same diets as for the previous treatment with monensin plus probiotic (Saccharomyces cerevisiae boulardii CNCM I-1079, ProTernative® 20; Lallemand Animal Nutrition at a dose of 1.0 x 10e10 cfu/animal/d) supplementation. Supplementation was offered for the first 42 days (21 days in the step-up phase and 21 days in the finishing diet with 900 g concentrate/kg DM), then both treatments were fed the same basal diet for another 76d, reaching 118 days in total. Pen was considered the experimental unit and data were analyzed using the MIXED procedure of SAS with Tukey test at 5% significance level. Final carcass weight was 1.69% greater for animals fed SCB (283.8 vs. 288.7 kg, P = 0.04). Total carcass weight gain (111.0 vs. 114.8 kg) and daily carcass weight gain (0.924 vs. 0.956 kg) tended (P = 0.06) to increase by 3.46% in SCB-fed animals compared to the CON ones. Gain yield (P = 0.39), biological efficiency (P = 0.35) and carcass yield (P = 0.71) did not differ between treatments. Probiotic supplementation with live yeast during the first 42 days in feedlot helped Nellore bulls optimize early on growth performance with an interesting carry-over effect on carcass gain through the total feedlot time.

Mature and stable intestinal microbiota in chickens is essential for health and production. Slow development of microbiota in young chickens prolongs the precarious period before reaching mature configuration. Whether probiotics can play a role in the early maturation of intestinal microbiota is unknown. To address this, day-old chicks were assigned into six groups: NC (basal diet), PC (virginiamycin), low (BPL) and high-dose (BPH) of Bacillus pumilus, and low (BSL) and high-dose (BSH) of Bacillus subtilis. Cecal contents at days 7, 14, 28 and 42 were used to analyze the treatment and time effects on the diversity and composition of microbiota. Overall, the alpha diversity was significantly decreased in the NC group between days 7 and 14, while this decline was prevented in the Bacillus subtilis probiotic (BSL and BSH) and even reversed in the BPH group. The beta-diversity showed significant responses of microbial communities to probiotics in first two weeks of life. Analyses of the abundance of microbiota reflected that members of the family Ruminococcaceae (Ruminnococcus, Oscillospira, Faecalibacterium, Butyricicoccus, and Subdoligranulum), which were dominant in mature microbiota, were significantly higher in abundance at day 14 in the probiotic groups. Conversely, the abundance of genera within the family Lachnospiraceae (Ruminococcus, Blautia, and Coprococcus) was dominant in early dynamic microbiota but was significantly lower in the probiotic groups at day 14. The Lactobacillus and Bifidobacterium abundance was higher, while the Enterobacteriaceae abundance was lower in the probiotic groups. In summary, the probiotics efficiently helped the cecal microbiota reach mature configuration earlier in life. These results could be used for the future manipulation of microbiota from the perspective of improving poultry performance.

A study was conducted to evaluate the effects of a live yeast supplement in the preweaning and finishing diets of Holstein bull calves on growth performance, carcass quality attributes and physiochemical traits. Holstein bulls (n = 39) at 5 days of age were randomly allocated to one of two treatment groups with 20 receiving no yeast supplement and 19 calves receiving the yeast supplement. The inclusion level of the yeast supplement in the pre-weaning diet was 54 mg/calf/day added to the milk replacer. During the post-weaning phase, the calves in the yeast treatment group received a pelleted feed with the yeast supplement already incorporated at 150g/tonne. The bull calves were slaughtered at 156 ± 15 days and the m. longissimus thoracis et lumborum was sampled for meat quality measurements. The live yeast supplement had no significant effect (P > 0.05) on average daily gain and final body weight of Holstein bull calves. Furthermore, carcass attributes and meat physiochemical traits were not influenced (P > 0.05) by diet. It was concluded that addition of yeast to preweaning and finishing diets of dairy bull calves has no effect on meat production and quality

High morbidity and mortality rates of calves dramatically impact the sustainability of the dairy industry. Probiotics are investigated for their potential to alleviate health challenges. The objective of the study was to determine the effect of live yeast Saccharomyces cerevisiae var. boulardii CNCM I-1079 (SB) supplementation in pre-weaning calves. Thirty Holstein calves were enrolled at d6 of age and were offered daily 8 L of milk replacer with ad-libitum access to water and pelleted starter. Calves were balanced in term of parity of the dam and birth weight and randomly assigned to two experimental groups, designated as supplemented and Control. Supplemented calves received 2x109 cfu/d of SB added in the milk replacer. Every abnormal health condition, such as gut and respiratory disorders, as well as therapeutic treatments were recorded daily for each animal. A linear mixed model was performed to assess the impact of the supplementation on the different variables measured. Two fecal samples were collected at d10 and d60 of the trial to analyze bacteria diversity and taxonomic composition by amplicon sequencing. The overall health was improved in SB calves with fewer diarrhea cases detected compared with Controls (0.7 vs 2.2/calf, respectively, P = 0.001) and fewer SB calves experiencing respiratory disease (6.3 vs 50% respectively, P = 0.090). Along with those observations, a lower number of SB calves received a therapeutic treatment (18.8 vs 62.5% respectively, P = 0.029). Consequently, SB calves weighed 3 kg more compared with the Controls at the end of the experiment (P = 0.087). SB calves significantly presented a greater relative abundance of Akkermansia, a genus involved in immune system maturation, and a greater proportion of Lactobacillales and Negativicutes (lactate users) indicating likely better adaptation of their fecal microbiota to the milk diet than in Controls.

Objectives were to determine whether live yeast (LY) supplementation would affect daily dry matter feed intake, body weight (BW), immune, and febrile responses to a viral-bacterial (VB) respiratory challenge. Crossbred heifers (N = 38, BW = 230 ± 16.4 kg) were allocated into a 2 × 2 factorial treatment arrangement: Factor 1 = roughage-based diet with or without LY (Saccharomyces cerevisiae boulardii CNCM I-1079, 62.5 g/hd/d), Factor 2 = VB, intranasal administration of bovine herpesvirus-1 (BHV-1, 2 ×10(8), PFU) on day 0 and endobronchial inoculation with Mannheimia haemolytica (5.4 × 10(10), CFU) on day 3, or intranasal saline administration followed by inoculation with phosphate buffer solution (PBS). Heifers were fed their respective diets for 27 d prior to VB challenge on day 0. Heifers were housed by treatment and group-fed using electronic feedbunks. Thermo-boluses (Medria; Châteaubourg, FR) measured rumen temperature (RUT) at 5-min intervals and rectal temperature and whole blood samples were collected on days 0, 3 to 8, 10, 13, and 15. Data were analyzed using repeated measures in the mixed procedure of SAS with fixed effects of day, diet, inoculation, and their interactions. Animals fed LY exhibited a 16% increase (P = 0.02) in neutrophils relative to CON. Diet × inoculation × day interactions were detected for monocytes and haptoglobin. The VB-LY had the greatest (P < 0.05) concentration of monocytes on day 4, followed by VB-CON which was greater (P < 0.05) than PBS treatments. Haptoglobin concentration was greatest (P < 0.02) for VB-CON on day 5, followed by VB-LY which was greater (P < 0.05) than PBS. Heifers supplemented with LY had less (P < 0.05) haptoglobin production than CON. The VB challenge produced nasal lesions that increased (P < 0.01) with day, reaching a zenith on day 6 with 70% of the nares covered with plaques, and increased (P < 0.05) neutrophils on days 3 to 5. The VB challenge increased RUT (P < 0.05) days 2 to 7 and rectal temperature (P < 0.05) on days 0 and 3 to 6. The increased rectal temperature on day 0 was likely due to increased ambient temperature at time of challenge, as VB heifers were processed after the PBS heifers to avoid contamination. The VB challenge was effective at stimulating immune responses, and RUT was effective for measuring febrile responses. These results indicate that prior LY supplementation altered the leukogram in response to VB challenge, suggestive of increased innate immune response.

BACKGROUND The effect of live yeast Saccharomyces cerevisiae strain CNCM I-1077 (SC) on the ruminal degradability of different forages commonly found in dairy diets in South America was evaluated. We also assessed if SC supplementation interacts with forage group to affect ruminal fiber degradability. Four non-lactating rumen-cannulated Holstein cows were randomly assigned to two treatment sequences: Control-SC-Control or SC-Control-SC, in a switchback design, with three 30-day periods. Cows in the SC treatment were supplied with 1 × 1010 colony-forming units of yeast daily via rumen cannula. In situ degradability of dry matter (DM) and neutral detergent fiber (aNDF) was measured in 15 forages collected in South America. Forages were assigned to one of three groups: corn silages; tropical grasses (sugarcane silages and tropical grass silages); and temperate grasses and alfalfa (oat silages, ryegrass silages, alfalfa silage, and alfalfa hay). RESULTS Cows supplemented with SC had higher (P = 0.05) counts of yeasts and lower (P = 0.03) concentration of lactate in rumen fluid. There was no interaction between forage group and yeast supplementation (P > 0.10) on in situ degradability. The SC increased DM (by 4.6%) and aNDF degradation (by 10.3%) at 24 h of incubation (P

This study aimed to evaluate the effect of probiotic (Saccharomyces cerevisiae boulardii CNCM I-1079) supplementation during feedlot adaptation period on performance of Nellore bulls. One-hundred ninety-eight Nellore bulls were used in a completely randomized block design, divided in 22 pens (9 animals/pen). Treatments were: CON – adaptation diet and finishing diet comprised of basal diet (with 28 ppm of monensin); and SCB – same diets as for the previous treatment with monensin plus probiotic (Saccharomyces cerevisiae boulardii CNCM I-1079, ProTernative® 20; Lallemand Animal Nutrition at a dose of 1.0 x 10e10 cfu/animal/d) supplementation. Supplementation was offered for the first 42 days (21 days in the step-up phase and 21 days in the finishing diet with 900 g concentrate/kg DM), then both treatments were fed the same basal diet for another 76d, reaching 118 days in total. Pen was considered the experimental unit. Growth data were analyzed using the MIXED procedure of SAS with Tukey test at 5% significance level, and a linear regression analysis was performed for the dry matter intake (DMI) data. During the first 42 days, average DMI did not differ; however, bulls fed SCB plateaued the curve of at 9.17 kg DMI/d earlier (39 days, R2 = 0.97) than those fed CON (43 days; R2 = 0.96) diets. Final body weight (509.5 vs. 518.0 kg, P = 0.02), total body weight gain (163.7 vs. 170.3 kg, P = 0.01) and average body weight daily gain (1.366 vs. 1.420 kg, P = 0.01) were greater for SCB-fed bulls. Feed efficiency of SCB-supplemented bulls was 8.05% greater than CON (P = 0.04). Probiotic supplementation with live yeast Saccharomyces cerevisiae boulardii CNCM I-1079 during the first 42 days in feedlot contributes to reaching the plateau of DMI curve earlier and improving overall performance of Nellore bulls during the total period.

The objective of this experiment was to determine if statistical process control (SPC) procedures coupled with remote continuous data collection could accurately differentiate between animals experimentally inoculated with a viral–bacterial (VB) challenge or phosphate buffer solution (PBS). Crossbred heifers (N = 38; BW = 230 ± 16.4 kg) were randomly assigned to treatments by initial weight, average daily gain (ADG), bovine herpes virus 1, and Mannheimia haemolytica serum titers. Feeding behavior, dry matter intake (DMI), animal activity, and rumen temperature were continuously monitored remotely prior to and following VB challenge. VB-challenged heifers exhibited decreased (P < 0.01) ADG and DMI, as well as increased (P < 0.01) neutrophils and rumen temperature consistent with a bovine respiratory disease (BRD) infection. However, none of the heifers displayed overt clinical signs of disease. Shewhart and cumulative summation (CUSUM) charts were evaluated, with sensitivity and specificity computed on the VB-challenged heifers (n = 19) and PBS-challenged heifers (n = 19), respectively, and the accuracy was determined as the average of sensitivity and specificity. To address the diurnal nature of rumen temperature responses, summary statistics (mean, minimum, and maximum) were computed for daily quartiles (6-h intervals), and these quartile temperature models were evaluated separately. In the Shewhart analysis, DMI was the most accurate (95%) at deciphering between PBS- and VB-challenged heifers, followed by rumen temperature (94%) collected in the 2nd and 3rd quartiles. Rest was most the accurate accelerometer-based traits (89%), and meal duration (87%) and bunk visit (BV) frequency (82%) were the most accurate feeding behavior traits. Rumen temperature collected in the 3rd quartile signaled the earliest (2.5 d) of all the variables monitored with the Shewhart, followed by BV frequency (2.8 d), meal duration (2.8 d), DMI (3.0 d), and rest (4.0 d). Rumen temperature and DMI remained the most accurate variables in the CUSUM at 80% and 79%, respectively. Meal duration (58%), BV frequency (71%), and rest (74%) were less accurate when monitored with the CUSUM analysis. Furthermore, signal day was greater for DMI, rumen temperature, and meal duration (4.4, 5.0, and 3.7 d, respectively) in the CUSUM compared to Shewhart analysis. These results indicate that Shewhart and CUSUM charts can effectively identify deviations in feeding behavior, activity, and rumen temperature patterns for the purpose of detecting sub-clinical BRD in beef cattle.

The transmission of passive immunity from the sow to the neonate piglets through colostrum is crucial for their future development. The aim of this experiment was to demonstrate that feeding the live yeast Saccharomyces cerevisiae boulardii CNCM I-1079 (SCB) increases the immunoglobulin G (IgG) concentration in colostrum. In total, 620 colostrum samples were taken from mixed-parity sows (1-9) in 11 farms in Colombia. There were 2 treatments: control (CON; standard feed in gestation and lactation), and SCB (CON + 1 × 109 colony forming units (CFU)/kg, fed from 3 weeks before the expected farrowing date). The samples were taken within the first 4 hours after the birth of the first piglet, from both sides of the teats of the sow, and immediately analyzed with a MA871 refractometer to obtain a °Brix value. Furthermore, each value was attributed to 1 of the 4 following categories regarding IgG concentration: Very good, Adequate, Limited, and Poor. Data were analyzed with SPSS Statistics 26.0 (IBM) and submitted to an analysis of variance with farm as random effect, parity rank and treatment as fixed effects, and their interactions. However, no interaction was found between any of the variables studied. Colostrum from sows in the SCB treatment displayed a higher °Brix value (P < 0.001) than the 1 from sows in the CON treatment. Additionally, the percentage of sows fitting the categories Very good and Adequate was greater in the SCB treatment than in the CON, and the one fitting the categories Limited and Poor was greater in the CON treatment than in the SCB. It is concluded that supplementing sows with Saccharomyces cerevisiae boulardii CNCM I-1079 from 3 weeks before farrowing increases IgG concentration in colostrum, helping the neonate piglets to acquire the passive immunity necessary to improve later performance.

International audience; The early development of immunity and microbiota in the gut of newborn calves can have life-long consequences. Gut microbiota and the intestinal barrier interplay after birth, establishing a homeostatic state whereby mucosal cells cohabit with microorganisms to develop a healthy gut. We hypothesized that postnatal codevelopment of gut immunity and microbiota could be influenced by early-life supplementation with live yeast. Starting from birth, calves either received a daily supplementation of Saccharomyces cerevisiae boulardii CNCM I-1079 (SCB, 10 x 10(9) cfu/d, n = 10) in the morning meal for 7 d or no supplementation (n = 10). Each animal received 2 adequate colostrum replacer meals at 2 and 12 h of life (expected total IgG fed = 300 g) before being fed milk replacer twice a day. Passive transfer of immunity (total protein, IgG, and IgA) through colostrum was evaluated and endogenous production of IgA was investigated by measuring IgA-producing plasma cells, IgA relative gene expression (PIGR and CD79A), and secretory IgA concentration in the gut. The concentration of targeted microbial groups was evaluated with quantitative PCR in the gut digesta collected at d 7 of life. Early SCB supplementation did not impair immunoglobulin absorption and all calves had successful passive transfer of immunity (serum IgG concentration >15 mg/mL at d 1 and d 7 of age). Although the expression of IgA relative gene expression (PIGR and CD79A) was not different, SCB calves had higher secretory IgA concentrations in the ileum (1.98 +/- 0.12 mg/g of dry matter; DM) and colon (1.45 +/- 0.12 mg/g of DM) digesta compared with control animals (1.18 and 0.59 +/- 0.12 mg/g of DM, respectively). In addition, the number of IgA-producing plasma cells were greater in both ileum (2.55 +/- 0.40 cells/mm(2)) and colon (3.03 +/- 0.40 cells/mm(2)) tissues for SCB calves compared with control (respectively 1.00 +/- 0.40 and 0.60 +/- 0.42 cells/mm(2)). Endogenous IgA production in the gut of SCB calves was enhanced, which could make them less prone to pathogen intrusion. In addition, SCB calves had higher Lactobacillus and tended to have higher Faecalibacterium prausnitzii in the jejunum compared with control calves, which suggests that SCB supplementation during early-life gut colonization may have a positive effect in newborn calves. Direct SCB supplementation or the cross-talk between SCB and bacteria may be responsible for stimulating IgA production and may play a key role in shaping early colonization in the gut of newborn calves.

This study evaluated the effects of inoculation of whole crop corn silage with a mixture of heterofermentative lactic acid bacteria (LAB) composed of Lactobacillus hilgardii and Lactobacillus buchneri on ensiling, aerobic stability, ruminal fermentation, total tract nutrient digestibility, and growth performance of beef cattle. Uninoculated control corn silage (CON) and silage inoculated with 3.0 × 105 cfu g-1 of LAB containing 1.5 × 105 cfu g-1 of L. hilgardii CNCM I-4785 and 1.5 × 105 cfu g-1 of L. buchneri NCIMB 40788 (INOC) were ensiled in silo bags. The pH did not differ (P > 0.05) between the two silages during ensiling but was greater (P < 0.001) for CON than INOC after 14 d of aerobic exposure (AE). Neutral detergent insoluble crude protein (NDICP) content (% of DM and % of CP basis) of terminal INOC silage was greater (P ≤ 0.05) than that of CON. In terminal silage, concentrations of total VFA and acetate were greater (P < 0.001), while water-soluble carbohydrates were lower (P < 0.001) for INOC than CON. Yeast and mold counts were lower for INOC than CON (P ≤ 0.001) in both terminal and aerobically exposed silages. The stability of INOC was greater (P < 0.001) than that of CON after 14 d of AE. Ruminal fermentation parameters and DMI did not differ (P > 0.05) between heifers fed the two silages, while there was a tendency (P ≤ 0.07) for lower CP and starch digestibility for heifers fed INOC than CON. Total nitrogen (N) intake and N retention were lower (P ≤ 0.04) for heifers fed INOC than CON. Dry matter intake as a percentage of BW was lower (P < 0.04) and there was a tendency for improved feed efficieny (G:F; P = 0.07) in steers fed INOC vs. CON silage. The NEm and NEg contents were greater for INOC than CON diets. Results indicate that inoculation with a mixture of L. hilgardii and L. buchneri improved the aerobic stability of corn silage. Improvements in G:F of growing steers fed INOC silage even though the total tract digestibility of CP and starch tended to be lower for heifers fed INOC are likely because the difference in BW and growth requirements of these animals impacted the growth performance and nutrient utilization and a greater proportion of NDICP in INOC than CON. Fil: Nair, Jayakrishnan. Lethbridge Research Centre; Canadá Fil: Huaxin, Niu. Inner Mongolia University for Nationals; China Fil: Andrada, Lidia Estefania. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina Fil: Yang, Hee-Eun. Lethbridge Research Centre; Canadá Fil: Chevaux, Eric. Lallemand SAS; Francia Fil: Drouin, Pascal. Lallemand Specialties Inc; Estados Unidos Fil: McAllister, Tim A.. Lethbridge Research Centre; Canadá Fil: Wang, Yuxi. Lethbridge Research Centre; Canadá

The objective of this experiment was to determine if statistical process control (SPC) procedures coupled with the remote continuous collection of feeding behavior patterns, accelerometer-based behaviors, and rumen temperature can accurately differentiate between animals experimentally inoculated with Mannheimia haemolytica (MH) or PBS. Thirty-six crossbred steers (BW = 352 ± 23 kg) seronegative for MH were randomly assigned to bronchoselective endoscopic inoculation with MH (n = 18) or PBS (n = 18). Electronic feed bunks were used to measure DMI and feeding behavior traits, accelerometer-based neck collars measured feeding- and activity-behavior traits, and ruminal thermo-boluses measured rumen temperature. Data were collected for 28 d prior to and following inoculation. Steers inoculated with MH exhibited elevated (P < 0.02) levels of neutrophils and rumen temperature indicating that MH challenge effectively stimulated immunologic responses. However, only nine of the MH steers exhibited increased serum haptoglobin concentrations indicative of an acute-phase protein response and one displayed clinical signs of disease. Shewhart charts (SPC procedure) were used for two analyses, and sensitivity was computed using all MH-challenged steers (n = 18), and a subset that included only MH-challenged haptoglobin-responsive steers (n = 9). Specificity was calculated using all PBS steers in both analyses. In the haptoglobin-responsive only analysis, DMI and bunk visit (BV) duration had the greatest accuracy (89%), with accuracies for head-down (HD) duration, BV frequency, time to bunk, and eating rate being less (83%, 69%, 53%, and 61%, respectively). To address the diurnal nature of rumen temperature, data were averaged over 6-h intervals, and quarterly temperature models were evaluated separately. Accuracy for the fourth quarter rumen temperature was higher (78%) than the other quarterly temperature periods (first = 56%, second = 50%, and third = 67%). In general, the accelerometer-based behavior traits were highly specific ranging from 82% for ingestion to 100% for rest, rumination, and standing. However, the sensitivity of these traits was low (0% to 50%), such that the accuracies were moderate compared with feeding behavior and rumen temperature response variables. These results indicate that Shewhart procedures can effectively identify deviations in feeding behavior and rumen temperature patterns to enable subclinical detection of BRD in beef cattle.

Objectives of this experiment were to examine the effects of live yeast (LY) supplementation on immunological, physiological, and behavioral responses in steers experimentally challenged with Mannheimia haemolytica (MH). Thirty-six crossbred Angus steers (BW = 352 ± 23 kg) seronegative for MH were allocated within a 2 × 2 factorial arrangement: Factor 1 = roughage-based diet with LY (Saccharomyces cerevisiae boulardii CNCM I-1079, 25 g·per steer daily) or negative control (CON). Factor 2 = bronchoselective endoscopic inoculation with MH or phosphate buffer solution (PBS). Steers were fed their respective diets for 28 d prior to MH challenge on day 0. Reticulo-rumen temperature (RUT; ThermoBolus, Medria) was measured continuously at 5-min intervals and rectal temperature on days -4, 0, 1, 2, 3, 5, 7, 10, and 14 relative to MH inoculation. Compared with PBS-treated steers, the steers inoculated with MH had increased (P 41 °C) 9 to 11 h post-MH challenge, whereas rectal temperature was increased (P < 0.04) in MH-inoculated steers on day 1 post-MH challenge. Supplementation with LY increased (P < 0.05) rectal temperature on days 0, 7, and 10, relative to CON steers. There were inoculation x day interactions (P < 0.01) for lymphocyte, neutrophil, leukocyte, and haptoglobin concentrations. Steers challenged with MH had increased (P < 0.05) neutrophil concentration from days 1 to 3, leukocyte concentration on days 1 and 2 and haptoglobin concentration on days 1 to 5 post-MH challenge compared with PBS-treated steers. Steers supplemented with LY exhibited increased (P < 0.02) cortisol throughout the study compared with the CON treatment. Following inoculation, MH-challenged steers exhibited reduced (P < 0.05) DMI, eating rate, frequency, and duration of bunk visit (BV) events compared with PBS-treated steers. Results from this study demonstrate that the experimental challenge model effectively stimulated acute-immune responses and behavioral changes that are synonymous with naturally occurring bovine respiratory disease (BRD). However, supplementation with LY minimally altered the impact of the MH challenge on physiological and behavioral responses in this study. Continuously measured RUT was more sensitive at detecting febrile responses to MH challenge than rectal temperature. These results serve to guide future research on behavioral and physiological alterations exhibited during a BRD infection.

The objective of this study was to evaluate the effects of Levucell SC (LY; Saccharomyces cerevisiae CNCM I-1077) supplementation on performance, feed efficiency, ruminal temperature, feeding behavior, and carcass quality traits in yearling steers. Forty-eight crossbred steers were randomly allocated into two treatments: (1) Control and (2) LY with two pen replicates per treatment (12 steers per pen). Steers were housed in pens equipped with GrowSafe and fitted with reticulo-rumen boluses. All steers were maintained on their respective dietary treatments until harvest to assess carcass traits. There were no differences amongst treatments in DMI, ADG, morbidity or mortality rates, ruminal temperature or F:G. Live-yeast supplemented steers had 17% greater (P = 0.05) backfat thickness than control steers, which resulted in a 13% increase in yield grade, with no differences in all other carcass traits. Live-yeast steers exhibited different feeding behavior patterns than control steers, such that LY steers approached the bunk 25 minutes earlier (P = 0.01) than control steers, had 22% greater (P < 0.05) bunk visit (BV) duration, 41% increased (P < 0.05) head down duration, 18% slower (P < 0.05) BV eating rates, and a tendency for 9% lower BV frequency. Meal criterion was 47% longer (P = 0.01) for LY steers resulting in a reduction (P = 0.07) in meal frequency. Additionally, LY steers consumed 27% longer meals (P < 0.05) that tended to be larger in size (P = 0.09). Although DMI was not different throughout the trial, LY displayed 10% decreased (P < 0.05) meal-eating rates due to longer meal lengths. Overall, LY steers approached the feed bunk sooner following feed delivery, ate fewer, but larger meals at a slower rate, and spent more time eating compared to control steers. Live-yeast supplementation clearly altered feeding behavior patterns, suggesting more favorable fermentation and the capability to mitigate metabolic stress in steers fed high-grain diets by altering meal patterns.

Aim of this study was to evaluate effects on growth, slaughter performance, behavior, and rumen environment parameters of dietary supplementation with a live yeast strain of Saccharomyces cerevisiae in a high-concentrate finishing diet fed to young Charolais bulls. A total 171 bulls (initial body weight (BW) = 442 ± 22.8 kg) were stratified by BW and assigned to one of two experimental groups: Control (85 bulls) and Yeast (86 bulls). Each group was allotted to 6 contiguous pens. All bulls were fed the same finishing diet ad libitum as a total mixed ration (TMR) at 0900 h. The live yeast strain of Saccharomyces cerevisiae CNCM I-1077 was added to the Yeast bull premix to target a daily dose of 5 g/bull. Bull final BW (743 ± 18.7 kg) and average daily gain (1.64 ± 0.12 kg) did not differ between groups. However, yeast increased dry matter (DM) intake (11.0 versus 10.4 kg/d; P = 0.04) and tended to reduce (P = 0.08) the number of days required for finishing. The effect of yeast on DM intake was particularly relevant in the first weeks of fattening, possibly as a sign of better adaptation by bulls to the high-energy concentration of the finishing diet. Carcass weights and dressing did not differ between treatments, but the likelihood of producing a carcass graded as excellent by conformation score was 2.15 times higher for Yeast than Control bulls (Chi-Square = 14.7 and 95% confidence interval = 1.42–3.27; P

The objective of this study was to investigate the effect of one specific strain of yeast, Saccharomyces cerevisiae boulardii CNCM I-1079 (SCB), on the growth performance, health, and fecal bacterial profile of veal calves. A total of 84 animals were enrolled in an experiment at a commercial veal farm for a total of 7 wk. Calves were fed twice a day with a milk replacer meal during the entire experiment and were randomly assigned to receive daily either SCB supplementation (10 × 109 cfu/d) or a placebo (CON). Individual feed intake and body weight were monitored on a daily and weekly basis, respectively. Fecal samples were collected at arrival to the veal facility (wk 0) and additional samples were taken on d 14 (wk 2) and d 49 (wk 7). These samples were subjected to 16S rRNA gene amplicon sequencing using Illumina MiSeq (Illumina Inc., San Diego, CA) to examine the bacterial profiles and real-time quantitative PCR to quantify Saccharomyces cerevisiae and specific bacterial groups. The significant increase of S. cerevisiae in the feces of SCB calves at wk 2 and 7 compared with wk 0 (respectively 1.7 × 107, 1.2 × 107, and 2.2 × 105 copy number of S. cerevisiae/g of feces) indicates a good survival of that yeast strain along the gastrointestinal tract. Supplementation of SCB did not improve overall growth performance with regard to average daily gain (ADG), final body weight, and feed intake. Nevertheless, a total of 69.1% of nonsupplemented calves had diarrhea and 28.6% experienced severe diarrhea, whereas 50.0% of the calves supplemented with SCB had diarrhea and 9.5% experienced severe diarrhea. With respect to antibiotic use, 89.7% of the diarrheic calves recorded in the CON group were treated, whereas only 66.7% of the SCB diarrheic calves received an antibiotic. In addition, diarrheic calves supplemented with SCB maintained an ADG similar to nondiarrheic animals, whereas the CON diarrheic calves had a significantly lower ADG in comparison with nondiarrheic CON calves. Fecalibacterium was the most predominant bacterial genus in fecal samples of nondiarrheic and diarrheic calves supplemented with SCB, whereas fecal microbiota was predominated by Collinsella in diarrheic calves from the CON group. Live yeast supplementation in milk replacer led to a decrease of diarrhea in milk-fed veal calves and the fecal microbiota of diarrheic calves maintained a healthy community similar to nondiarrheic animals, with Fecalibacterium being the predominant genus.

Calves are born with a naïve immune system at birth and undergo rapid changes in terms of immunity. This study focused on evaluating the effect of S. boulardii CNCMI-1079 (SCB) supplementation from birth on immunoglobulin A (IgA) production in the gut of neonate dairy calves. Holstein bull calves (n = 20) were delivered naturally and immediately removed from the dam, and housed in individual straw-bedded pens with a random assignment to a treated group (supplementation with SCB: 10 × 109 CFU/d in each morning meal) or a control group (no supplementation). All the calves received two first meals of a standardized colostrum at 2 h and 12 h after birth followed by two meals per day of milk replacer (7.5% of birth BW; 260 g/kg CP; 160 g/kg crude fat, at 150g/L). Calves were euthanized at 7 d of age and samples from jejunum, ileum and colon were collected. The concentration of IgA and the gene expressions of polymeric Ig receptor (pIgR) and a receptor of plasma B cells (CD79α) were compared between the two groups and among the locations. The expression of CD79α was up-regulated in the ileum compared to jejunum and colon tissues (P < 0.01), whereas pIgR down-regulated in the ileum compared to jejunum and colon (P < 0.01). The supplementation of SCB increased the IgA concentration in the ileum and colon of treated calves compared to the control calves (respectively 1.98 ± 0.09 vs 1.18 ± 0.15 mg/g DM of ileum content, and 1.45 ± 0.14 vs 0.59 ± 0.06 mg/g DM of colon content, P < 0.001). The results suggest that one of the mechanisms by which SCB exerts an immunoprotective effect in the gut is by stimulation of IgA’s secretion which may play a major role in mucosal protection in neonatal calves.

Objectives of this experiment were to examine the effects of live yeast (LY) supplementation on immunological, physiological, and behavioral responses in steers experimentally challenged with Mannheimia haemolytica (MH). Thirty-six crossbred Angus steers (BW = 352 ± 23 kg) seronegative for MH were allocated within a 2 × 2 factorial arrangement: Factor 1 = roughage-based diet with LY (Saccharomyces cerevisiae boulardii CNCM I-1079, 25 g·per steer daily) or negative control (CON). Factor 2 = bronchoselective endoscopic inoculation with MH or phosphate buffer solution (PBS). Steers were fed their respective diets for 28 d prior to MH challenge on day 0. Reticulo-rumen temperature (RUT; ThermoBolus, Medria) was measured continuously at 5-min intervals and rectal temperature on days −4, 0, 1, 2, 3, 5, 7, 10, and 14 relative to MH inoculation. Compared with PBS-treated steers, the steers inoculated with MH had increased (P < 0.05) RUT from 2 to 24 h, reaching a zenith (>41 °C) 9 to 11 h post-MH challenge, whereas rectal temperature was increased (P < 0.04) in MH-inoculated steers on day 1 post-MH challenge. Supplementation with LY increased (P < 0.05) rectal temperature on days 0, 7, and 10, relative to CON steers. There were inoculation x day interactions (P < 0.01) for lymphocyte, neutrophil, leukocyte, and haptoglobin concentrations. Steers challenged with MH had increased (P < 0.05) neutrophil concentration from days 1 to 3, leukocyte concentration on days 1 and 2 and haptoglobin concentration on days 1 to 5 post-MH challenge compared with PBS-treated steers. Steers supplemented with LY exhibited increased (P < 0.02) cortisol throughout the study compared with the CON treatment. Following inoculation, MH-challenged steers exhibited reduced (P < 0.05) DMI, eating rate, frequency, and duration of bunk visit (BV) events compared with PBS-treated steers. Results from this study demonstrate that the experimental challenge model effectively stimulated acute-immune responses and behavioral changes that are synonymous with naturally occurring bovine respiratory disease (BRD). However, supplementation with LY minimally altered the impact of the MH challenge on physiological and behavioral responses in this study. Continuously measured RUT was more sensitive at detecting febrile responses to MH challenge than rectal temperature. These results serve to guide future research on behavioral and physiological alterations exhibited during a BRD infection.

This study aimed to identify the effect of supplementing Saccharomyces cerevisiae boulardii CNCM I-1079 (SB) in milk replacer on the fecal bacterial composition of veal calves. Veal calves (6 d ± 3 d of age, n = 84) were randomly assigned to two treatments: CON (no SB; n = 42 calves) and SB (n = 42 calves). From the first day of arrival, SB was added into milk replacer (supplying 10 X 10Firmicutes (65.3%), Actinobacteria (11.7%) and Proteobacteria (11.0%). Among them, 5 phyla were detected (defined as the relative abundance being above 0.1% and present in at least half of the samples in each group). A total of 63 bacterial genera were detected, predominately Faecalibacterium (15.0%), Collinsella (10.5%), and Escherichia-Shigella (9.3%). In SB calves compared to controls, the relative abundance of Escherichia-Shigella was lower (P < 0.05), and those of Dorea and Streptococcus tended to be lower (P < 0.1). Sampling time affected the relative abundance of Faecalibacterum, Escherichia-Shigella, Bacteroides, and Dorea (P < 0.05), and tended to affect that of Collinsella and Streptococcus (P < 0.1). Sampling time and supplementation of SB interactively affected the relative abundance of Escherichia-Shigella (P < 0.05) and tended to affect that of Faecalibacterium, Streptococcus, Lachnospiraceae UCG-008, and Dorea (P < 0.1). These results showed that SB could alter the composition of the fecal bacteria in a time-dependent manner, suggesting that SB could be capable of manipulating gut bacteria in pre-weaned veal calves. Key Words

The objective of this study was to investigate the effects of one specific strain of Saccharomyces cerevisiae boulardii CNCMI-1079 (SB) on the health and performance of male dairy calves. Neonatal diarrhea is a common disease in young calves creating significant economic loss and welfare concerns for the Canadian livestock industry. Probiotics may provide a solution to this challenge as they have been shown to stimulate healthy microbiota, prevent the proliferation of enteric pathogens and improve mucosal immunity in young animals. At a commercial veal farm, a total of 84 calves were enrolled in this experiment for a total of 53 days. A control group (n = 42) was fed individually 2 times/d with milk replacer and the treatment group (n = 42) was fed with the addition of SB (10 billion colony-forming units/d) in milk replacer. No differences were observed with regards to average daily gain between the two groups (P = 0.15), however, daily health parameters were impacted. With respect to mortality, six control calves and two calves fed SB died during the experiment. A total of 67% of control calves had diarrhea and 29% experienced severe diarrhea, whereas, 50% of supplemented calves were affected by diarrhea and only 10% experienced severe diarrhea (P < 0.05). In fact, the average number of diarrhea cases (fecal score ≥ 2 for at least 2 days) was 4.3 ± 2.5 in the control group, whereas calves supplemented with SB experienced only 3.0 ± 2.3 diarrhea cases (P < 0.05). With respect to antibiotic use, 81% of the control calves were treated with antibiotics during the experiment, whereas 66% of supplemented calves were treated. This study demonstrates that, despite no improvement in calf growth, the health of the calves was improved with the addition of SB in the milk replacer.

There is an increasing movement against use of antibiotic growth promoters in animal feed. Prebiotic supplementation is a potential alternative to enhance the host’s natural defense through modulation of gut microbiota. In the present study, the effect of mannan oligosaccharide (MOS) and virginiamycin (VIRG) on cecal microbial ecology and intestinal morphology of broiler chickens raised under suboptimal conditions was evaluated. MOS and VIRG induced different bacterial community structures, as revealed by denaturing gradient gel electrophoresis of 16S rDNA. The antibiotic treatment reduced cecal microbial diversity while the community equitability increased. A higher bacterial diversity was observed in the cecum of MOS-supplemented birds. Quantitative polymerase chain reaction results indicated that MOS changed the cecal microbiota in favor of the Firmicutes population but not the Bacteroidetes population. No difference was observed in total bacterial counts among treatments. MOS promoted the growth of Lactobacillus spp. and Bifidobacterium spp. in the cecum and increased villus height and goblet cell numbers in the ileum and jejunum. These results provide a deeper insight into the microbial ecological changes after supplementation of MOS prebiotic in poultry diets.

Bulls (n = 770, average age = 127 days, SD = 53 days of age) were fitted with an activity monitoring device for three months to study if behavior could be used for early detection of diseases. The device measured the number of steps, lying time, lying bouts, and frequency and time of attendance at the feed bunk. All healthy bulls (n = 699) throughout the trial were used to describe the normal behavior. A match-pair test was used to assign healthy bulls for the comparison vs. sick bulls. The model was developed with 70% of the data, and the remaining 30% was used for the validation. Healthy bulls did 2422 &plusmn, 128 steps/day, had 28 &plusmn, 1 lying bouts/day, spent 889 &plusmn, 12 min/day lying, and attended the feed bunk 8 &plusmn, 0.2 times/d for a total of 95 &plusmn, 8 min/day. From the total of bulls enrolled in the study, 71 (9.2%) were diagnosed sick. Their activities changed at least 10 days before the clinical signs of disease. Bulls at risk of becoming sick were predicted 9 days before clinical signs with a sensitivity and specificity of 79% and 81%, respectively. The validation of the model resulted in a sensitivity, specificity, and accuracy of 92%, 42%, and 82 %, respectively, and a 50% false positive and 12.5% false negative rates. Results suggest that activity-monitoring systems may be useful in the early identification of sick bulls. However, the high false positive rate may require further refinement.

© 2012 Chaucheyras-Durand et al., licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Use of Yeast Probiotics in Ruminants: Effects and Mechanisms of Action on Rumen pH, Fibre Degradation, and Microbiota According to the Diet

International audience; Experiments were carried out to determine the effects of supplementation upon milk production and growing performances of Martinik hair sheep. Ewes weighing 49 kg LW were used in a 2-season experimental study. In the first trial, 3 energy supplement levels were offered to ewes suckling single lambs. The adjusted level (A, 8 ewes) was supplied to ensure that the litter had a daily weight gain (DWG) of 250 g. High (H, 8 ewes) and low (L, 8 ewes) levels were 150% and 75% of level A, respectively. In the second trial, comparative use of the H level was studied with 3 animal requirement levels: ewes suckling single lambs (SI, same ewes as H ewes), twins (TW, 8 ewes) and triplets (TR, 6 ewes), respectively. The experimental design was replicated in a second lambing season. The basal diet was chopped Digitaria decumbens hay (0.6 UFL, 4.6% CP) offered ad libitum. Supplements were composed of maize (65% ), soya bean (3% ), fish meal (8% ) and dehydrated alfalfa (24% ). The milk production (MP) of ewes on the L diet was lower ($P < 0.05$) than that of ewes on the A and H diets: 1142, 1415 and 1518 g$\cdot$d$^{-1}$, respectively. H-fed ewes fattened during the lactating period while A and L ewes respectively maintained and lowered their body condition score (BCS). Differences recorded for lamb DWG were low, but this trait reached a maximum of 248 g$\cdot$d$^{-1}$. MP varied significantly ($P < 0.05$) according to the litter size. Individual DWG was different for single, twin and triplet lambs ($P < 0.001$): 261, 188 and 143 g$\cdot$d$^{-1}$, respectively. In intensive breeding conditions, recommended daily energy allowances taking into account a good BCS of ewes for successive reproduction are 1.47 UFL for single-suckling ewes and 2.17 UFL for twin-suckling ewes, in order to obtain a DWG of the litter of 250 and 400 g$\cdot$d$^{-1}$, respectively.; Alimentation des brebis allaitantes Martinik élevées dans des conditions intensives : effets de différents niveaux de concentrés ou de la taille de portée. L'effet de la complémentation sur les performances des ovins allaitants a été étudié chez les brebis à poils Martinik pesant 49 kg de poids vif. Dans un premier essai, trois niveaux énergétiques ont été comparés chez les brebis allaitant un agneau. Le niveau ajusté (A, 8 brebis) a été apporté pour assurer un gain moyen quotidien (GMQ) théorique de 250 g$\cdot$j$^{-1}$. Les niveaux bas (B, 8 brebis) et haut (H, 8 brebis) représentaient 75 et 150 % de A, respectivement. Dans un deuxième essai, un gradient de besoins a été testé chez les brebis recevant la ration H, à portée simple (S, mêmes brebis que celles de l'essai1), double (D, 8 brebis) et triple (T, 6 brebis). Le schéma expérimental a été répété lors d'une deuxième saison de mise-bas. Les animaux recevaient ad libitum du foin de Digitaria decumbens (0,6 UFL, 4,6 % MAT). Le concentré était composé de maïs (65 % ), de farine de soja (3 % ), de farine de poisson (8 % ) et de luzerne déshydratée (24 % ). La production laitière (PL) des brebis recevant la ration B a été plus faible ($P < 0,05$) que celle des brebis des lots A et H : 1142, 1415 et 1718 g$\cdot$j$^{-1}$, respectivement. Les notes d'état corporel (NEC) ont diminué, stagné et augmenté pour les brebis des lots B, A et H, respectivement. Le GMQ des agneaux simples a été peu différent entre les rations et a atteint au maximum 248 g pour le lot H. La PL des brebis de taille de portée multiple a été supérieure de 30 % à celle des brebis à portée simple. Le GMQ des portées doubles a été voisin de 400 g. Des recommandations sont formulées dans le cas d'un élevage intensif : 1,47 et 2,17 UFL$\cdot$j$^{-1}$ pour des brebis pesant près de 50 kg et allaitant respectivement un et deux agneaux.