Evaluation of essential oils and a prebiotic for newborn dairy calves

Effects of Microencapsulated Essential Oils on Growth and Intestinal Health in Weaned Piglets

The study investigated the effects of microencapsulated essential oils (MEO) on the growth performance, diarrhea, and intestinal microenvironment of weaned piglets. The 120 thirty-day-old weaned piglets (Duroc × Landrace × Yorkshire, 8.15 ± 0.07 kg) were randomly divided into four groups and were fed with a basal diet (CON) or CON diet containing 300 (L-MEO), 500 (M-MEO), and 700 (H-MEO) mg/kg MEO, respectively, and data related to performance were measured. The results revealed that MEO supplementation increased the ADG and ADFI in weaned piglets (p < 0.05) compared with CON, and reduced diarrhea rates in nursery pigs (p < 0.05). MEO supplementation significantly increased the duodenum's V:C ratio and the jejunal villi height of weaned piglets (p < 0.05). The addition of MEO significantly increased the T-AOC activity in the jejunum of piglets (p < 0.05), but only L-MEO decreased the MDA concentration (p < 0.01). H-MEO group significantly increases the content of isobutyric acid (p < 0.05) in the piglet colon, but it does not affect the content of other acids. In addition, MEO supplementation improved appetite in the nursery and increased the diversity and abundance of beneficial bacteria in the intestinal microbiome. In conclusion, these findings indicated that MEO supplementation improves growth and intestinal health in weaned piglets.

Milk replacer galacto-oligosaccharide (GOS) inclusion rates for neonatal calves

Galacto-oligosaccharide (GOS) is a prebiotic isolated from whey. This study evaluated the optimal inclusion rate for improving growth and health performance of neonatal calves. Eighty-eight 2-5-d old Holstein bull calves were blocked by initial BW and randomly allocated to 1 of 4 treatments using a RCBD. Treatments comprised a 22:20 (CP: fat) amino acid balanced milk replacer (MR) with GOS added at the rate of 0 g/d (Control or GOS0), 2 g/d (GOS2), 4 g/d (GOS4), and 8 g/d (GOS8). Calves received 0.283 kg MR in 1.9 L fed 2 x/d for the first 14 d, then increased to 0.42 kg in 2.84 L fed 2x/d through d 35, followed by 0.42 kg MR in 2.84 L fed 1x/d through d 42, followed by weaning. The GOS inclusion rate remained constant as milk volume increased. Calves fed GOS at 2, 4, and 8 g/d demonstrated similar growth performance compared with calves fed GOS0. Calves fed GOS4 demonstrated a carryover effect into post-weaning resulting in a tendency for increased (P < 0.08) BW (82.5, 83.0, 85.3, and 83.1 kg for GOS0, GOS2, GOS4, and GOS8, respectively), BW gains (37.8, 38.2, 41.3 and 38.6 kg), and ADG (687, 696, 751, and 701 g/d). The ADG was increased by 9.3% when feeding calves GOS4 compared with calves fed GOS0. Calf starter DMI was greater at 7 (1.73,1.86, 1.95, and 1.83 kg/d) and 8 (2.34, 2.50, 2.60, 2.49 kg/d) wk of age for calves fed GOS4 compared with calves fed GOS0 with remaining treatments being intermediate and similar. Feed conversion (0.552, 0.529, 0.563, 0.545 kg/kg) was greater for calves fed GOS0 and GOS4 g/d compared with calves fed GOS2 with calves fed GOS8 being intermediate and similar. Body frame gains were similar for calves fed all GOS inclusion rates. A treatment by week interaction at wk 2 indicated that calves fed GOS2 demonstrated greater fecal score = 0 d than calves fed the remaining treatments, indicating less scours. In conclusion, supplementing GOS to a milk replacer at 4 g/d fed to neonatal calves improved growth performance without compromising health conditions.

Effect of parenteral micronutrient supplementation at birth on immunity, growth, and health in preweaning dairy heifers

This randomized clinical trial aimed to determine the extent to which injectable micronutrient supplementation at birth can improve intranasal vaccine response by ameliorating oxidative stress in dairy calves from birth to weaning. For this, 120 Holstein heifer calves were enrolled at birth and randomly allocated into one of 4 groups. The 4 groups included 3 commercially available micronutrient supplements (selenium, copper, zinc, and manganese; selenium and vitamin E; and vitamins E, A, and D) and one control (saline). Calves received an intranasal vaccine against the respiratory viruses parainfluenza 3, bovine herpesvirus type 1 (BHV-1), and bovine respiratory syncytial virus (BRSV) within the first week of life. Body weight and hip height (HH) were recorded, and a blood sample and nasal secretion sample were collected at birth before treatment and vaccine administration, as well as weekly until weaning at 8 wk. Health scores, including thoracic ultrasound assessment, were recorded weekly from wk 1 to wk 8. Farm treatment records were collected after the completion of the study. Serum micronutrient concentrations were determined from birth to weaning to identify micronutrient status, and serum blood metabolites were analyzed as markers of nutrient utilization. Redox balance was determined in serum as a ratio of reactive oxygen and nitrogen species to antioxidant capacity, known as the oxidant status index (OSi). Intranasal vaccine response was quantified as anti-BRSV and anti-BHV-1 IgA concentrations in nasal secretions. Linear mixed models with repeated measures were built for micronutrient concentrations, blood metabolites, redox balance, IgA concentrations, BW, and HH. Pre-planned contrasts of the control and supplemented groups were also built for the primary outcome of IgA concentrations. A logistic regression mixed model was built for health events and treatment of disease. Serum selenium concentrations were greater in calves receiving supplements containing Se throughout the first 4 wk of life. However, we did not observe any consistent differences in the other micronutrients. The metabolic biomarkers indicate that supplemented calves had better energy status, as suggested by lower BHB and nonesterified fatty acids concentrations. Supplemented calves showed improved redox balance, as indicated by lower OSi throughout the first week of life. Calves supplemented with antioxidants at birth had higher anti-BRSV IgA than control calves. Our results indicate an improved immune response to vaccines in calves supplemented with antioxidants at birth. However, this did not translate to growth and health performance, as we did not find any differences in average daily gain or incidence of health events throughout the preweaning period. This study provides evidence that improving the antioxidant capacity might improve vaccine response, and further research is required to investigate the appropriate frequency and dose of supplementation to improve calf growth and health.

Effects of castration and eucalyptus oil supplementation on growth performance, nutrient digestibility, and blood-immunity indicators of male Holstein calves

The purpose of this study was to investigate the effects of early castration and eucalyptus oil (EUC) supplementation on dry matter intake (DMI), growth performance, and immune response of Holstein calves. Fifty-six male Holstein calves 52 d old and with an initial body weight (BW) of 63.5 ± 5.27 kg were used. The animals were blocked by BW and randomly assigned into 1 of the 4 treatment groups in a randomized complete block design with a 2 (no castration vs. castration) × 2 (without vs. with EUC) factorial arrangement of treatments. The treatments were (1) uncastrated calves fed without EUC, (2) uncastrated calves fed 0.5 g/d EUC (EUC group), (3) castrated calves (steers) fed without EUC (castrated group), and (4) steers fed with 0.5 g/d EUC (castrated + EUC). The experiment was 8 wk long, including pre- and postweaning (weaned at 72 d). The EUC × castrated interactions were not significant for DMI, growth performance, nutrient digestibility, and immune response. Castration did not affect the DMI, final BW, average daily gain (ADG), or feed efficiency, except that the ADG was greater for bull calves than for steers at postweaning. Supplementation with EUC increased DMI pre- and postweaning and increased the ADG of weaned calves. Digestibility in the total digestive tract was not affected by castration (except for organic matter digestibility), whereas adding EUC improved the digestibility of dry matter, acid detergent fiber, and crude protein. Blood concentration of IL-6 at d 94 was decreased by feeding EUC. These results indicate that the EUC could be fed to either intact or castrated dairy calves to promote growth and health postweaning; castration before weaning may reduce ADG and cause inflammatory stress without affecting feed intake or feed efficiency.

Essential oil blend supplementation in the milk replacer of dairy calves: Performance and health

Supplementation of dairy calves with essential oils in the liquid diet can reduce the incidence and severity of infectious diseases and promote better performance. Our objective was to evaluate an essential oil blend containing peppermint, eucalyptus, and menthol crystals and its effect on performance and health during the pre and postweaning period of dairy calves. At birth, 40 dairy calves (34 males and 6 females) were blocked according to sex and birth weight, randomly assigned to one of two treatments-commercial milk replacer diluted at 14% (MR) and the same liquid diet plus essential oil blend (MREO) at a dose of 4 mL per calf per day, divided into two meals during the first 28 days of life. Calves were individually housed and fed 6 L/d of the liquid diet, divided into two meals, and received starter concentrate and water ad libitum. Weaning was gradually reduced by 1L per day at d 51 until complete weaning at 56 days. After weaning, calves were evaluated until 70 days of age, when the experimental period ended. Intake, fecal, and health scores were evaluated daily, weight and body measures were recorded weekly, and blood parameters were evaluated at weeks 1, 2, 3, 4, and 8. Calves fed MREO tended to have higher total dry matter intake during the preweaning period. Furthermore, MREO calves had lower health scores and fewer days with a health score ≥ 4 (suggestive of bronchopneumonia), tended to lower coughing days and fewer veterinary interventions preweaning, and tended to lower health scores postweaning. The supplementation with a blend of essential oils containing peppermint, eucalyptus, and menthol crystals can reduce respiratory problems. Further studies are needed to investigate the dose and the supplementation period.

Chemical Composition, Antioxidant and Antibacterial Activity of Two Different Essential Oils Against Mastitis Associated Pathogens

Mastitis is one of the most common and costly diseases affecting dairy cows worldwide. Since antibiotic resistance has become a global threat to both animal and human health, it is becoming more urgent to continuously search for new therapeutical alternatives for the control and treatment of bovine mastitis. Hence, our research aimed to test the therapeutic use of two essential oils (EOs) based on their chemical composition, antibacterial and antioxidant potential. The present study was conducted by collecting milk samples from the cows diagnosed with clinical or subclinical mastitis with the aim of isolating and identifying bacterial strains. The antioxidant potential of essential oils of Menthae piperitae (MP) and Melissa officinalis (MO) was evaluated in several in vitro assays. In the MP EO, a total of 38 compounds were identified, with menthol as the dominant compound, whereas in MO EO 51 compounds were identified. Furthermore, the values of minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) have been used to quantitatively measure the antibacterial activity of each essential oil. In accordance with which, MP EO samples exhibited a higher degree of antibacterial activity than MO EO. Thus, EOs have been shown to be promising alternatives to antibiotics because of their availability, biodegradability, and lower risk of side effects as compared with conventional, antimicrobial treatment. Nevertheless, further clinical studies are needed to test the potential role of EOs in treating mastitis in dairy cows.

Growth performance, nutrient digestibility, blood parameters, and carcass characteristics by lambs fed an oregano and cobalt blend

Shifting ruminal fermentation via feeding a blend of oregano (Organum vulgare L.) essential oils and Co-lactate (EOC; Rum-A-Fresh, Ralco, Inc. Marshall, MN) could improve lamb growth and carcass performance. Eighteen Suffolk × Little Han Tail F1 male lambs (20.3 ± 0.23 kg BW and approximately 3 months old) were randomly assigned using a completely random design to one of three treatments. Treatments were (1) EOC0: basal ration without EOC, (2) EOC4: basal ration plus 4 g/d EOC, and (3) EOC7: basal ration plus 7 g/d EOC. Initial and 24 d BW was similar (P > 0.10), but at 48 and 72 d, lambs fed EOC7 demonstrated greater (P = 0.01) BW compared with EOC0 fed lambs, while lambs fed EOC4 were intermediate and similar (P > 0.05). Average daily gains (ADGs) for 0-24 and 0-72 d were greater (P < 0.05) for lambs fed EOC4 and EOC7 compared with lambs fed EOC0, while DM intake was similar (P > 0.10). Feed conversions for 0-24 d were improved (P < 0.02) for lambs fed EOC4 and EOC7 compared with lambs fed EOC0. However, 0-72-d feed conversions were greater (P < 0.01) for lambs fed EOC7 compared to lambs fed EOC0, with lambs fed EOC4 being intermediate and similar (P > 0.05). DM, NDF, and ADF digestibilities were similar (P > 0.10) among treatments, while CP digestibility was greater (P < 0.01) for lambs fed EOC4 and EOC7 compared with lambs fed EOC0. Carcass weight and dressing percentages were improved (P < 0.01) for lambs fed EOC7 compared with lambs fed EOC0 and EOC4. Head width was greater (P > 0.01) for lambs fed EOC7 compared with lambs fed EOC0 and EOC4, while rump width was greater (P > 0.01) for lambs fed EOC4 and EOC7 compared with lambs fed EOC0. Plasma triglyceride and cholesterol concentrations were lower (P < 0.05) for lambs fed EOC4 and EOC7 compared with lambs fed EOC0, while albumin, total serum protein, and glucose concentrations were greater (P < 0.05) for lambs fed EOC4 and EOC7 compared with lambs fed EOC0. Feeding an EOC blend as an alternative antibiotic growth promoter at 4 and 7 g/d linearly improved lamb growth performance, feed conversions, frame growth, carcass weights, dressing percentages, and immunity.

Gut microbiome colonization and development in neonatal ruminants: Strategies, prospects, and opportunities

Colonization and development of the gut microbiome is a crucial consideration for optimizing the health and performance of livestock animals. This is mainly attributed to the fact that dietary and management practices greatly influence the gut microbiota, subsequently leading to changes in nutrient utilization and immune response. A favorable microbiome can be implanted through dietary or management interventions of livestock animals, especially during early life. In this review, we explore all the possible factors (for example gestation, colostrum, and milk feeding, drinking water, starter feed, inoculation from healthy animals, prebiotics/probiotics, weaning time, essential oil and transgenesis), which can influence rumen microbiome colonization and development. We discuss the advantages and disadvantages of potential strategies used to manipulate gut development and microbial colonization to improve the production and health of newborn calves at an early age when they are most susceptible to enteric disease. Moreover, we provide insights into possible interventions and their potential effects on rumen development and microbiota establishment. Prospects of latest techniques like transgenesis and host genetics have also been discussed regarding their potential role in modulation of rumen microbiome and subsequent effects on gut development and performance in neonatal ruminants.

Lactobacillus plantarum GB LP-1 as a direct-fed microbial for neonatal calves

Direct-fed microbial feed additives with potential to enhance growth performance, gut health, and immunity have gained considerable popularity in neonatal calf production. Lactobacillus plantarum GB LP-1 (LP) produced by a proprietary fermentation process could be a viable direct-fed microbial feed for neonatal calves. The hypothesis was that feeding LP may ease transitioning from milk replacer (MR) to calf starter (CS) by improving gut health and appetite, while minimizing health challenges from pathogens and stress to improve growth performance. The experimental objective was to evaluate LP in an MR feeding program at 3 inclusion rates. Fifty-one 2- to 5-d-old Holstein bull calves were randomly assigned to 1 of 3 treatments using a randomized complete block design. Treatments were (1) Control (LP0): LP fed at 0 g/d; (2) LP4: LP fed at 4 g/d; and (3) LP8: LP fed at 8 g/d. Calves were fed MR at 0.57 kg/d for 14 d via bucket, which was increased to 0.85 kg/d until 35 d, and were then fed once daily at 0.425 kg/d with weaning after d 42 of the 56-d experiment. Calves were fed at 0630 and 1800 h in equal allotments, with access at all times to free-choice water and a pelleted CS with 25.5% crude protein. Calves demonstrated a linear growth response to increasing LP inclusion rate: calves fed LP8 gained more body weight (33.0, 36.9, and 37.7 kg for LP0, LP4, and LP8, respectively) than calves fed LP0, with calves fed LP4 being intermediate and similar. The 0-to-42-d (MR feeding phase) average daily gain (ADG; 562.9, 595.9, and 655.7 g/d) and 0-to-56-d ADG (588.6, 658.4, and 673.0 g/d) demonstrated linear responses, with calves fed LP8 having greater ADG than calves fed LP0, and calves fed LP4 being intermediate and similar. Total CS intake was similar among calves fed all treatments (66.3, 69.0, and 72.5 kg/56 d), which resulted in a quadratic response in feed efficiency (0.50, 0.53, and 0.52 kg of gain/kg of dry matter) for calves fed LP4 compared with calves fed LP0, with calves fed LP8 being intermediate and similar. Fecal scores improved linearly with increasing LP inclusion rate. These data demonstrate that feeding Lactobacillus plantarum GB LP-1 to neonatal calves improves gut health to increase growth performance at 4 and 8 g/d, while feed efficiency was greatest at 4 g/d.

Feeding a calf starter containing monensin alone or in combination with an oregano, and cobalt blend to Holstein calves

Gut health is critically important for growing neonatal calves, and nutritional technologies are needed to prevent disease and stress challenges. Previous work feeding monensin (MON) in combination with an oregano, prebiotic, and cobalt-lactate (EOC) blend had demonstrated improved calf gut health and growth performance. The objective of this study was to evaluate the growth performance of calves fed MON and EOC alone or in combination. Eighty (80) newborn Holstein (37) female and (43) male calves were randomly assigned to one of four treatments arranged in a 2 × 2 factorial (MON and EOC). Treatments were: 1) Control: without MON or EOC added to the calf starter (CS); 2) MON: 50.8 mg/kg CS (Elanco, Greenfield, IN); 3) EOC: 44.1 mg/kg CS (Rum-A-Fresh, Ralco Inc. Marshall, MN); 4) MON + EOC: MON and EOC added to CS. Calves were fed colostrum followed by whole milk through weaning at 42 d, while CS was fed ad libitum through the 70-d experimental period. The MON by EOC interaction was found to be nonsignificant (P > 0.41) for growth performance. Calves fed without or with MON demonstrated similar (P > 0.70) body weight (BW; 68.7 and 68.9 kg without and with MON, respectively), while calves fed EOC demonstrated greater (P < 0.01) BW (67.3 and 70.4 kg without and with EOC, respectively) compared with calves fed without EOC. Calves fed a CS containing MON were similar (P > 0.47) in average daily gain (ADG; 0.88 and 0.91 kg/d) compared with calves fed without MON; however, feeding calves a CS with EOC increased (P < 0.01) ADG (0.84 and 0.95 kg/d) by 13% through the 70-d experimental period compared with calves not fed EOC. Frame measurements indicated that the greater ADG was due to increased (P < 0.10) frame growth for calves fed essential oils (EO) compared with calves fed without EO. A MON by EOC interaction (P < 0.01) for serum propionate concentration demonstrated calves fed MON + EOC and EOC were greater (P < 0.05) compared with calves fed Control, while calves fed MON were intermediate and different (P < 0.05). Feeding calves a CS with EOC increased (P < 0.04) immunoglobulin A, immunoglobulin G, and immunoglobulin M concentrations compared with calves fed without EOC. A MON by EOC interaction was detected (P < 0.01) for total tract starch digestibility for calves fed EOC or MON + EOC demonstrating greater (P < 0.05) starch digestibilities than Control-fed calves. These data demonstrate that EOC and MON fed in combination was not beneficial for enhancing the growth performance, but that calf growth performance can be improved with EOC compared with MON.