Effects of supplementing direct-fed microbials on health and growth of pre-weaning Gyr × Holstein dairy calves.

This study aimed to evaluate the effects of direct-fed microbials (DFM) on health and growth responses of pre-weaning Bos indicus × B. taurus (Gyr × Holstein) crossbred calves. Ninety newborn heifer calves [initial body weight (BW) 35 ± 4.0 kg] were used. At birth, calves were ranked by initial BW and parity of the dam and assigned to: 1) whole milk without DFM supplementation (CON; n = 30), 2) whole milk with the addition of 1.0 g/calf per day of a Bacillus-based DFM (BAC; n = 30), or 3) whole milk with the addition of 1.0 g/calf per day of BAC and 1.2 g/calf per day of Enterococcus faecium 669 (MIX; n = 30). Milk was fed individually during the study (77 d) and the BAC and MIX treatments were offered daily throughout the 77-d pre-weaning period. All calves were offered a starter supplement and corn silage starting on d 1 and 60 of age, respectively. Milk and starter supplement intake were evaluated daily, and BW was recorded on d 0 and at weaning (d 77). Diarrhea and pneumonia were assessed daily, and fecal samples were collected on d 0, 7, 14, 21, and at weaning (d 77) for assessment of the presence of bacterial and protozoal pathogens via qPCR. All data were analyzed using SAS (v. 9.4) with calf as the experimental unit and using single-df orthogonal contrasts (BAC + MIX vs. CON; BAC vs. MIX). Daily feeding of DFM, regardless of type, improved weaning BW. Odds ratio for occurrence of pneumonia was lower for DFM-supplemented calves, but occurrence of both did not differ between BAC and MIX calves. No Salmonella spp. or E. coli F41 were detected in any of the calves. The proportion of calves positive for E. coli F17 was greater for DFM calves on d 7 (92 and 96% vs. 81% for BAC, MIX, and CON, respectively), 21 (13 and 26% vs. 7% for BAC, MIX, and CON, respectively), and at weaning (48 and 35% vs. 22% for BAC, MIX, and CON, respectively). For C. difficile, more DFM calves were positive on d 7 (65 and 30% vs. 35% for BAC, MIX, and CON, respectively) and 14 (20 and 28% vs. 7% for BAC, MIX, and CON, respectively), but also greater for BAC vs. MIX on d 7. More CON calves were positive for C. perfringens on d 14 (14% vs. 3 and 8% for CON, BAC, and MIX, respectively) compared with DFM-fed calves. Incidence of calves positive for C. perfringens was greater in BAC vs. MIX on d 7 (50 vs. 18%), and greater for MIX vs. BAC at weaning (9 vs. 0%). For protozoa occurrence, a lower proportion of DFM calves were positive for Cryptosporidium spp. on d 7 (58 and 48% vs. 76% for BAC, MIX, and CON, respectively), but opposite results were observed on d 21 for Cryptosporidium spp. (3 and 11% vs. 0% for BAC, MIX, and CON, respectively) and Eimeria spp. on d 14 (7 and 8% vs. 0% for BAC, MIX, and CON, respectively) and 21 (50 and 59% vs. 38% for BAC, MIX, and CON, respectively). In summary, DFM feeding alleviated the occurrence of pneumonia, improved growth rates, while also modulating the prevalence of bacteria and protozoa in pre-weaning Gyr × Holstein calves.

Effects of supplementing a Bacillus-based direct-fed microbial on performance, nutrient digestibility, rumen fermentation characteristics, and metabolic responses of lactating dairy cows.

This experiment was conducted to evaluate the effects of feeding a Bacillus-based direct-fed microbial (DFM) on performance, nutrient digestibility, rumen fermentation, and metabolic response of lactating dairy cows. Sixty-eight lactating (50 ± 6 d in milk) Holstein-Friesian (n = 20) and Swedish Red (n = 48) cows were enrolled to a 15-wk experiment. Cows were blocked by breed, lactation number, and days in milk and, within blocks, assigned to 1 of the 2 treatments: (1) basal partial mixed ration (PMR) without DFM (n = 34; CON) or (2) basal PMR with the addition of 3 g/head per day of a DFM containing Bacillus licheniformis and Bacillus subtilis (n = 34; DFM). The DFM was mixed in a protein pellet, whereas the CON group was fed the same pellet without DFM (1 kg/cow per day). The PMR contained 53% clover grass silage and 47% compound feed plus 3 kg of a concentrate (dry matter basis) offered during milking. Milk yield and production efficiency were recorded daily, whereas milk samples were collected for 24 h every second week of the study for milk composition. During the experimental period, fecal, rumen fluid, and blood samples were collected from each cow for apparent nutrient digestibility, rumen fermentation, and metabolic responses, respectively. All data were analyzed using the MIXED procedure of SAS. No treatment effects were observed on cows final body weight and daily dry matter intake. However, cows fed DFM had a greater milk yield, milk production efficiency, lactose and total solids yield, and also tended to have a greater energy-corrected milk production efficiency and milk protein yield. No significant differences were observed on nutrient digestibility and total volatile fatty acids, but molar proportion of acetate was greater for cows fed DFM. In contrast, molar proportion of propionate was greater and butyrate tended to be greater for CON. Cows fed DFM had greater mean plasma insulin-like growth factor-I (IGF-I), but no differences were observed for plasma glucose and insulin. In summary, supplementing a Bacillus-based DFM benefited productive responses of lactating dairy cows, while also modulating rumen fermentation and serum IGF-I.

Supplementation of direct-fed microbial Enterococcus faecium 669 affects performance of preweaning dairy calves.

Optimization and support of health and performance of preweaning dairy calves is paramount to any dairy operation, and natural solutions, such as probiotics, may help to achieve such a goal. Two experiments were designed to evaluate the effects of direct-fed microbial (DFM) Enterococcus faecium 669 on performance of preweaning dairy calves. In experiment 1, twenty 4-d-old Holstein calves [initial body weight (BW) 41 ± 2.1 kg] were randomly assigned to either (1) no probiotic supplementation (CON; n = 10) or (2) supplementation with probiotic strain E. faecium 669 during the preweaning period (DFM; n = 10) at 2.0 × 1010 cfu/kg of whole milk. Full individual BW was analyzed every 20 d for average daily gain (ADG) and feed efficiency (FE) determination. In experiment 2, thirty 4-d-old Holstein calves (initial BW 40 ± 1.9 kg) were assigned to the same treatments as in experiment 1 (CON and DFM). The DFM supplementation period was divided into period I (from d 0 to 21) and II (from d 22 to 63), with weaning occurring when animals were 67 d of age. During the entire experimental period, DFM was mixed into the whole milk at a rate of 1.5 × 1010 and 2.5 × 109 cfu/kg of whole milk/calf per day for periods I and II, respectively (6-time reduction). Full individual BW was taken every 21 d. As a routine of the experiment, calves were monitored daily, and diarrhea cases were evaluated using a daily 3-point fecal score. For both experiments, all data were analyzed using calf as the experimental unit. In experiment 1, DFM-supplemented calves were heavier on d 40 (+ 4.5 kg) and 60 (+ 6.5 kg) and had a greater ADG (+ 118 g) versus CON. In experiment 2, supplementation with DFM significantly tended to reduce diarrhea occurrence. Treatment × day and treatment × week interactions were observed for BW, ADG, and gain-to-feed ratio. Dairy calves supplemented with DFM were 1.8 and 3.5 kg heavier on d 42 and at weaning, respectively, and had a greater ADG from d 21 to 42 (+ 52 g) and 42 to 63 (+ 77 g) and gain-to-feed ratio from d 42 to 63 (+ 8.6%). In summary, supplementation of E. faecium 669 to dairy calves improved preweaning performance, even when the dose of the DFM was reduced by 6- to 8-times. Additionally, initial promising results were observed on diarrhea occurrence, but further studies are warranted.

Effects of feeding different probiotic types on metabolic, performance, and carcass responses of Bos indicus feedlot cattle offered a high-concentrate diet.

Two experiments were designed to evaluate the effects of different probiotic combinations on rumen fermentation characteristics, performance, and carcass characteristics of feedlot Bos indicus beef bulls offered a high-concentrate diet. In experiment 1, 30 rumen-fistulated Nellore steers were blocked by initial body weight (BW = 350 ± 35.0 kg) and within blocks (n = 10), animals were randomly assigned to receive: 1) high-concentrate diet without probiotic supplementation (n = 10; CONT), 2) CONT plus 1 g per head of a probiotic mixture containing three strains of Enterococcus faecium and one strain of Saccharomyces cerevisiae (3.5 × 109 CFU/g; n = 10; EFSC), and 3) CONT plus 2 g per head of a probiotic mixture containing Bacillus licheniformis and Bacillus subtilis (3.2 × 109 CFU/g; n = 10; BLBS). The experimental period lasted 35 d, being 28 d of adaptation and 7 d of sampling. From day 34 to day 35 of the experimental period, ruminal fluid and fecal samples were collected every 3 h, starting immediately before feeding (0 h) for rumen fermentation characteristics and apparent nutrient digestibility analysis, respectively. In experiment 2, 240 Nellore bulls were ranked by initial shrunk BW (375 ± 35.1 kg), assigned to pens (n = 4 bulls per pen), and pens randomly assigned to receive the same treatments as in experiment 1 (n = 20 pens per treatment). Regardless of treatment, all bulls received the same step-up and finishing diets throughout the experimental period, which lasted 115 d. In both experiments, data were analyzed as orthogonal contrasts to partition-specific treatment effects: 1) probiotic effect: CONT vs. PROB and 2) probiotic type: EFSC vs. BLBS (SAS Software Inc.). In experiment 1, no contrast effects were observed on nutrient intake, overall nutrient digestibility, and rumen fermentation analyses (P ≥ 0.13). Nonetheless, supplementation of probiotics, regardless of type (P = 0.59), reduced mean acetate:propionate ratio and rumen ammonia-N concentration vs. CONT (P ≤ 0.05). In experiment 2, no significant effects were observed for final BW and dry matter intake (P ≥ 0.12), but average daily gain and feed efficiency tended to improve (P ≤ 0.10) when probiotics were offered to the animals. Probiotic supplementation or type of probiotic did not affect carcass traits (P ≥ 0.22). In summary, supplementation of probiotics containing a mixture of E. faecium and S. cerevisiae or a mixture of B. licheniformis and B. subtilis reduced rumen acetate:propionate ratio and rumen ammonia-N levels and tended to improve the performance of feedlot cattle offered a high-concentrate diet.

Two experiments were designed to evaluate the effects of different probiotic combinations on rumen fermentation characteristics, performance, and carcass characteristics of feedlot Bos indicus beef bulls offered a high-concentrate diet. The two probiotics consisted of a mixture containing three strains of Enterococcus faecium and one strain of Saccharomyces cerevisiae or a mixture of Bacillus licheniformis and Bacillus subtilis. Supplementation of probiotics, regardless of type, reduced acetate:propionate ratio, and mean rumen ammonia-N concentration and tended to improve the performance of feedlot cattle offered a high-concentrate diet, demonstrating the potential of this technology to be used as a feed additive for beef cattle.

Effects of a Bacillus-based direct-fed microbial on in vitro nutrient digestibility of forage and high-starch concentrate substrates.

Two experiments evaluated the effects of a Bacillus-based direct-fed microbial (DFM) on in vitro dry matter (DM) and neutral detergent fiber (NDF; experiment 1) and starch (experiment 2) digestibility of a variety of ruminant feedstuffs. In experiment 1, 10 forage sources were evaluated: ryegrass, alfalfa hay, leucaena, corn silage, spinifex, buffel grass, flinders grass, Mitchell grass, Rhodes grass hay, and Queensland bluegrass. Experimental treatments were control (forages with no probiotic inoculation; CON) and forage sources inoculated with a mixture containing Bacillus licheniformis and Bacillus subtilis (3.2 × 109 CFU per g; DFM). In vitro DM and NDF digestibility were evaluated at 24- and 48-h post-treatment inoculation. Treatment × hour interactions were noted for IVDMD (in vitro dry matter digestibility) and IVNDFD (in vitro neutral detergent fibre digestibility) (P ≤ 0.05). More specifically, DFM inoculation increased (P ≤ 0.03) IVDMD at 24 h in four forages and increased 48-h IVDMD (P ≤ 0.02) in alfalfa hay, ryegrass, leucaena, and Mitchell grass hay, but opposite results were observed for Queensland bluegrass (P < 0.01). A 24- and 48-h IVNDFD increased following DFM inoculation (P ≤ 0.02) in five forage sources, but reduced for Queensland bluegrass (P < 0.01). When the forages were classified according to their quality, main treatment effects were detected for IVDMD (P ≤ 0.02) and IVNDFD (P < 0.01). In experiment 2, five common cereal grains were evaluated-high-density barley (82 g/100 mL), low-density barley (69 g/100 mL), corn, sorghum, and wheat-under the same treatments as in experiment 1. In vitro starch digestibility (IVSD) was evaluated at 6- and 12-h following treatment inoculation. Treatment × hour interactions were observed for starch digestibility in three out of five concentrate sources (P ≤ 0.001). Inoculation of DFM yielded greater 24-h starch digestibility for high-, low-density barley, and wheat (P ≤ 0.02), but also greater at 48 h in wheat (P < 0.0001). Moreover, mean starch digestibility improved for corn and sorghum inoculated with DFM (P < 0.01). Using a Bacillus-based DFM (B. licheniformis and B. subtilis) improved the mean in vitro DM and NDF digestibility of different forage sources of varying qualities (based on crude protein content). Similarly, IVSD was also greater following DFM inoculation, highlighting the potential of this probiotic to improve nutrient digestibility and utilization in the beef and dairy cattle herd.

Dobutamine stress echocardiography-induced broken heart syndrome (Takotsubo Syndrome).

We report a case of dobutamine stress echocardiography-induced Takotsubo syndrome in a 76-year-old hypertensive patient with clinical complaints of chest pain in an elective visit to the cardiologist. Dobutamine-stress-echocardiography was requested to rule out chest pain of coronary origin. During the test, at peak exercise, echocardiogram showed apical akinesia and electrocardiogram showed ST-segment elevation in D1, AVL, and V2. The patient was hospitalized and underwent coronary angiography, which showed normal coronary arteries and left ventricular apical ballooning. During follow-up, the patient's condition remained stable, with regression of the manifestations 21 days after the initial presentation.

Síndrome do coração partido (Síndrome de Takotsubo) induzida por ecocardiograma de estresse com dobutamina / Síndrome del corazón roto (síndrome de Tako-Tsubo) inducido por ecocardiograma de esfuerzo con dobutamina / Dobutamine stress echocardiography-induced broken heart syndrome (Takotsubo Syndrome)

Relatamos um caso de síndrome de Takotsubo induzida por ecocardiograma de estresse com dobutamina em uma paciente de 76 anos, hipertensa com queixas clínicas de dor precordial, em consulta cardiológica eletiva. Para exclusão de dor torácica de etiologia coronariana foi solicitado ecocardiograma de estresse com dobutamina. O exame foi realizado e, no pico do esforço máximo, o ecocardiograma mostrou acinesia apical com o eletrocardiograma mostrando supradesnivelamento do segmento ST em D1, AVL e V2. A paciente foi internada e submetida a coronariografia, que mostrou coronárias normais e VE com balonamento apical. A paciente evoluiu estável com reversão do quadro 21 dias após o quadro inicial.

We report a case of dobutamine stress echocardiography-induced Takotsubo syndrome in a 76-year-old hypertensive patient with clinical complaints of chest pain in an elective visit to the cardiologist. Dobutamine-stress-echocardiography was requested to rule out chest pain of coronary origin. During the test, at peak exercise, echocardiogram showed apical akinesia and electrocardiogram showed ST-segment elevation in D1, AVL, and V2. The patient was hospitalized and underwent coronary angiography, which showed normal coronary arteries and left ventricular apical ballooning. During follow-up, the patient's condition remained stable, with regression of the manifestations 21 days after the initial presentation.

Relatamos un caso de síndrome de Tako-Tsubo inducido por ecocardiograma de esfuerzo con dobutamina en una paciente de 76 años, hipertensa con quejas clínicas de dolor precordial, en consulta cardiológica electiva. Para exclusión de dolor torácico de etiología coronaria se solicitó ecocardiograma de esfuerzo con dobutamina. El examen fue realizado, y en el pico de esfuerzo máximo, el ecocardiograma mostró acinesia apical con el electrocardiograma mostrando supradesnivel del segmento ST en D1, AVL y V2. La paciente fue internada y sometida a coronariografía, que mostró coronarias normales y VI con abombamiento apical. La paciente evolucionó estable con reversión del cuadro 21 días después del cuadro inicial.