Comparison between intrauterine application of an antibiotic and an herbal product to treat clinical endometritis in dairy cattle - A randomized multicentre field study.

Uterine diseases are main indications for antibiotic use in dairy cows. To test a non-antibiotic treatment option, we compared the effect of an intrauterine cephapirin (Metricure®; cefapirin benzathin 500 mg per dosis; CEPH) with an intrauterine applied herbal product (25 ml of EucaComp® PlantaVet containing alcoholic extracts of Calendula officinalis L., Mellissa officinalis L., Origanum majorana L. and Eucalyptus globulus Labill. (EUC)) on the clinical cure of endometritis. Examinations of 816 cows between 21 and 35 days after calving were performed and cases of clinical endometritis (n = 169) were included. Diagnosis based on a scoring system for vaginal discharge. Study animals were randomly assigned to one of two treatment groups and treated immediately. After excluding animals with incomplete datasets, 136 cows (EUC: n = 61; CEPH: n = 75) remained for the final analysis. In total, 64% (EUC: 61%, CEPH: 67%) of analysed endometritis cases were considered as clinically cured 14 ± 2 days after the first treatment, 15% stayed uncured after the application of a maximum of two consecutive treatments, leading to an overall clinical cure rate of 85% (EUC: 82%, CEPH: 88%). No statistically difference in clinical cure rates could be observed between both treatment groups nor 14 ± 2 days after the first treatment (p = 0.956) neither regarding the overall cure rate (p = 0.923). In conclusion, the clinical cure of dairy cows' endometritis after the intrauterine application of the herbal product was non-inferior to the intrauterine application of the antibiotic cephapirin. These results could contribute to reduce the antimicrobial use in the daily veterinary routine treatment of endometritis.

Carcass and meat characteristics of Nellore young bulls fed diet using cottonseed cake as a replacer of the forage fiber source.

The aim of this study was to assess the effects of substituting traditional forage fiber sources with cottonseed cake in the diet on both the quantitative and qualitative characteristics of carcass and meat in Nelore young bulls. Twenty-four Nelore steers starting with an average weight of 377.8 ± 43.5 kg, were individually housed in stalls and provided with individualized feeding over a 112-day confinement period. The study followed a completely randomized design with two treatments and 12 replications. The diets incorporated either whole plant corn silage (WPCS) and, cottonseed cake (CSC) as fiber sources, at a rate of 300 g/kg of dry matter. The CSC diet promoted higher carcass weight. Aging animal meat for seven days significantly decreased the shear force from 83.4 to 71.6 N. Although diets did not influence meat composition, WPCS diet provided higher concentrations of C16:1, C18:1n9c, C18:3n3, and C22:2 acid, and CSC diet higher concentrations of C15:0, C18:1n9t, C18:2n6c, and 20:3n3. The WPCS diet provided higher concentrations of monounsaturated fatty acids and ω9, and the CSC diet had higher concentrations of ω6 and ω6:ω3 ratio in meat. Cottonseed cake used as a fiber source increases the concentration of polyunsaturated fatty acids and ω6 fatty acids in the meat of young bulls finished in feedlot.

The Difference of Milk-Derived Extracellular Vesicles from Cow Colostrum and Mature Milk on miRNAs Expression and Protecting Intestinal Epithelial Cells against Lipopolysaccharide Damage.

Intestinal epithelial cells (IECs) play crucial roles in forming an essential barrier, providing host defense against pathogens and regulating nutrients absorption. Milk-derived extracellular vesicles (EVs) within its miRNAs are capable of modulating the recipient cell function. However, the differences between colostrum and mature milk EVs and their biological function in attenuating intestinal epithelial cell injury remain poorly understood. Thus, we carried out the present study to characterize the difference between colostrum and mature milk-derived miRNA of EVs and the effect of colostrum and mature milk EVs on the proliferation, apoptosis, proinflammatory cytokines and intestinal epithelial barrier related genes in IEC-6 induced by LPS. Differential expression of 329 miRNAs was identified between colostrum and mature milk EVs, with 185 miRNAs being downregulated and 144 upregulated. In addition, colostrum contains a greater number and protein concentration of EVs than mature milk. Furthermore, compared to control, EVs derived from colostrum significantly inhibited the expression of apoptosis- (Bax, p53, and caspase-3) and proinflammatory-related genes (TNFα, IL6, and IL1ß). EVs derived from mature milk did not affect expression of apoptosis-related genes (Bax, p53, bcl2, and caspase-3). The EVs derived from mature milk significantly inhibited the expression of proinflammatory-related genes (TNFα and IL6). Western blot analysis also indicated that colostrum and mature milk EVs significantly decreased the apoptosis of IEC-6 cells. The EdU assay results showed that colostrum and mature milk EVs significantly increased the proliferation of IEC-6 cells. The expression of intestinal barrier-related genes (TJP1, CLDN1, OCLN, CDX2, MUC2, and IGF1R) was significantly promoted in IEC-6 cells after colostrum and mature milk EVs addition. Importantly, colostrum and mature milk EVs significantly relieved the LPS-induced inhibition of proliferation and intestinal barrier-related genes expression and attenuated apoptosis and proinflammatory responses induced by LPS in IEC-6 cells. Flow cytometry and Western blot analysis also indicated that colostrum and mature milk EVs significantly affect the apoptosis of IEC-6 cells induced by LPS. The results also indicated that EVs derived from colostrum had better effects on inhibiting the apoptosis- and proinflammatory cytokines-related genes expression. However, the EVs derived from mature milk exhibited beneficial effects on intestinal epithelial barrier protection. The present study will provide a better understanding of the role of EVs derived from colostrum and milk in dairy cows with different responses in the regulation of intestinal cells function, and also presents new evidence for the change of EVs cargos during various stages of lactation.

The effect of ginger (Zingiber officinale L.) liquid extract on growth, immune response, antioxidant defence mechanism, and general health of Holstein calves.

This study was carried out to examine the effects of ginger liquid extract (GLE) on the growth, immune response, antioxidative defence mechanism, and general health of Holstein calves. Sixteen calves (4-d old) were included in the experiment and randomly assigned to groups, and they were fed whole milk containing GLE at a rate of 0, 0.50, 0.72, and 1% of the milk amount consumed. Calves consuming 1% GLE were weaned at an earlier age and gained better body weight (BW) compared to the other groups. The group fed with 0.50% GLE consumed less daily starter than the other groups. The administration of GLE resulted in a non-significant decrease in fecal score (FS), the number of days with diarrhea (DDN), and illness (IDN) among the calves. Notably, the 1% GLE exhibited a significant inhibitory effect on the growth of E. coli, while its effect on the growth of other pathogenic bacteria was not statistically significant. Despite the non-significant reduction in malondialdehyde (MDA), total oxidative status (TOS), and oxidative stress index (OSI) values, the 1% GLE demonstrated support for antioxidative defence mechanism and immune response. The results indicated that 1% GLE can be effective in promoting the health of calves by enhancing their immune response and antioxidant capacity. This suggests that incorporating 1% GLE into their overall well-being, potentially leading to improved health outcomes and performance in calf rearing operations.

The addition of curcumin to the diet of post-weaning dairy calves: effects on ruminal fermentation, immunological, and oxidative responses.

Incorporating Curcumin into animal diets holds significant promise for enhancing both animal health and productivity, with demonstrated positive impacts on antioxidant activity, anti-microbial responses. Therefore, this study aimed to determine whether adding Curcumin to the diet of dairy calves would influence ruminal fermentation, hematologic, immunological, oxidative, and metabolism variables. Fourteen Jersey calves were divided into a control group (GCON) and a treatment group (GTRA). The animals in the GTRA received a diet containing 65.1 mg/kg of dry matter (DM) Curcumin (74% purity) for an experimental period of 90 days. Blood samples were collected on days 0, 15, 45, and 90. Serum levels of total protein and globulins were higher in the GTRA group (P < 0.05) than the GCON group. In the GTRA group, there was a reduction in pro-inflammatory cytokines (IL-1ß and IL-6) (P < 0.05) and an increase in IL-10 (which acts on anti-inflammatory responses) (P < 0.05) when compared to the GCON. There was a significantly higher (P < 0.05) concentration of immunoglobulin A (IgA) in the serum of the GTRA than the GCON. A Treatment × Day interaction was observed for haptoglobin levels, which were higher on day 90 in animals that consumed Curcumin than the GCON (P < 0.05). The catalase and superoxide dismutase activities were significantly higher (P < 0.05) in GTRA, reducing lipid peroxidation when compared to the GCONT. Hematologic variables did not differ significantly between groups. Among the metabolic variables, only urea was higher in the GTRA group when compared to the GCON. Body weight and feed efficiency did not differ between groups (meaning the percentage of apparent digestibility of dry matter, crude protein, and acid detergent fiber (ADF) and neutral detergent fiber (NDF). There was a tendency (P = 0.09) for treatment effect and a treatment x day interaction (P = 0.05) for levels of short-chain fatty acids in rumen fluid, being lower in animals that consumed curcumin. There was a treatment vs. day interaction (P < 0.05) for the concentration of acetate in the rumen fluid (i.e., on day 45, had a reduction in acetate; on day 90, values were higher in the GTRA group when compared to the GCON). We conclude that there was no evidence in the results from this preliminary trial that Curcumin in the diet of dairy calves interfered with feed digestibility. Curcumin may have potential antioxidant, anti-inflammatory, and immune effects that may be desirable for the production system of dairy calves.

Differential responses of rumen and fecal fermentation and microbiota of Liaoning cashmere goats after 2-hydroxy-4-(methylthio) butanoic acid isopropyl ester supplementation.

The 2-hydroxy-4-(methylthio) butanoic acid isopropyl ester (HMBi), a rumen protective methionine, has been extensively studied in dairy cows and beef cattle and has been shown to regulate gastrointestinal microbiota and improve production performance. However, knowledge of the application of HMBi on cashmere goats and the simultaneous study of rumen and hindgut microbiota is still limited. In this study, HMBi supplementation increased the concentration of total serum protein, the production of microbial protein in the rumen and feces, as well as butyrate production in the feces. The results of PCoA and PERMANOVA showed no significant difference between the rumen microbiota, but there was a dramatic difference between the fecal microbiota of the two groups of Cashmere goats after the HMBi supplementation. Specifically, in the rumen, HMBi significantly increased the relative abundance of some fiber-degrading bacteria (such as Fibrobacter) compared with the CON group. In the feces, as well as a similar effect as in the rumen (increasing the relative abundance of some fiber-degrading bacteria, such as Lachnospiraceae FCS020 group and ASV32), HMBi diets also increased the proliferation of butyrate-producing bacteria (including Oscillospiraceae UCG-005 and Christensenellaceae R-7 group). Overall, these results demonstrated that HMBi could regulate the rumen and fecal microbial composition of Liaoning cashmere goats and benefit the host.

Measuring bioavailability, utilization, and excretion of rumen-protected lysine in lactating cows using an isotope technique.

Supplementing a diet with rumen-protected amino acids (AAs) is a common feeding strategy for efficient production. For a cost-effective use of rumen-protected AA, the accurate bioavailability of rumen-protected amino acids should be known and their metabolism after absorption needs to be well understood. The current study determined the bioavailability, absorption, utilization, and excretion of rumen-protected Lys (RP-Lys). Four ruminally cannulated cows in a 4 × 4 Latin square design (12 d for diet adaptation; 5 or 6 d for total collections) received the following treatments: L0, a basal diet; L25, the basal diet and L-Lys infused into the abomasum to provide 25.9 g/d L-Lys; L50, the basal diet and L-Lys infused into the abomasum to provide 51.8 g/d L-Lys; and RPL, the basal diet supplemented with 105 g/d (as-is) of RP-Lys to provide 26.7 g of digestible Lys. During the last 5 or 6 d in each period, 15N-Lys (0.38 g/d) was infused into the abomasum for all cows to label the pool of AA, and the total collection of milk, urine, and feces were conducted. 15N enrichment of samples on d 4 and 5 were used to calculate the bioavailability and Lys metabolism. We used a model containing a fast AA turnover (≤ 5 d) and slow AA turnover pool (> 5 d) to calculate fluxes of Lys. The Lys flux to the fast AA turnover pool (absorbed Lys + Lys from the slow AA turnover pool to fast AA turnover pool) was calculated using 15N enrichment of milk Lys. The flux of Lys from the fast AA turnover pool to milk and urine was calculated using 15N transfer into milk and urine. Then, absorbed Lys was estimated by the sum of Lys flux to milk and urine assuming no net utilization of Lys by body tissues. Duodenal Lys flow was estimated by 15N enrichment of fecal Lys. The bioavailability of RP-Lys was calculated from duodenal Lys flows and Lys absorption for RPL. Increasing Lys supply from L25 to L50 increased Lys utilization for milk by 9 g/d but also increased urinary excretion by 10 g/d. For RPL, absorbed Lys was estimated to be 136 g/d where 28 g of absorbed Lys originated from RP-Lys. In conclusion, 68% of bioavailability was obtained for RP-Lys. The Lys provided from RP-Lys was not only utilized for milk protein (48%) but also excreted in urine (20%) after oxidation.

Evaluation of the mechanism of Gong Ying San activity on dairy cows mastitis by network pharmacology and metabolomics analysis.

OBJECTIVES: The goal of this investigation was to identify the main compounds and the pharmacological mechanism of the traditional Chinese medicine formulation, Gong Ying San (GYS), by infrared spectral absorption characteristics, metabolomics, network pharmacology, and molecular-docking analysis for mastitis. The antibacterial and antioxidant activities were determined in vitro. METHODS: The chemical constituents of GYS were detected by ultra-high-performance liquid chromatography Q-extractive mass spectrometry (UHPLC-QE-MS). Related compounds were screened from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP, http://tcmspw.com/tcmsp.php) and the Encyclopedia of Traditional Chinese Medicine (ETCM, http://www.tcmip.cn/ETCM/index.php/Home/) databases; genes associated with mastitis were identified in DisGENT. A protein-protein interaction (PPI) network was generated using STRING. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment screening was conducted using the R module. Molecular-docking analyses were performed with the AutoDockTools V1.5.6. RESULTS: Fifty-four possible compounds in GYS with forty likely targets were found. The compound-target-network analysis showed that five of the ingredients, quercetin, luteolin, kaempferol, beta-sitosterol, and stigmasterol, had degree values >41.6, and the genes TNF, IL-6, IL-1ß, ICAM1, CXCL8, CRP, IFNG, TP53, IL-2, and TGFB1 were core targets in the network. Enrichment analysis revealed that pathways associated with cancer, lipids, atherosclerosis, and PI3K-Akt signaling pathways may be critical in the pharmacology network. Molecular-docking data supported the hypothesis that quercetin and luteolin interacted well with TNF-α and IL-6. CONCLUSIONS: An integrative investigation based on a bioinformatics-network topology provided new insights into the synergistic, multicomponent mechanisms of GYS's anti-inflammatory, antibacterial, and antioxidant activities. It revealed novel possibilities for developing new combination medications for reducing mastitis and its complications.

Effects of supplementing cassava root silage to grazing dairy cows on nutrient utilization, milk production and composition in the tropics.

The current study evaluated the effects of supplementing cassava root silage (CRS) to dairy cows grazing on Megathyrsus maximus cv Mombasa on nutrient intake and digestibility, as well as on milk production and composition. Ten primiparous Girolando cows with average body weight ± (SEM) of 373.45 ± (63.55) kg were used in a replicated 5 × 5 Latin square. Animals were subjected to five treatments: (I) grazing cows without supplementation (WCS); (II) grazing cows provided with 5 kg DM of supplement without CRS (0 g/kg DM of CRS) or including (III) 260, (IV) 520, and (V) 780 g/kg DM of CRS. Statistical analyses were performed using the PROC MIXED of SAS with significance at P < 0.05. Intake of neutral detergent fiber (NDF) and ether extract decreased (P < 0.01), while intake of non-fiber carbohydrates increased (P < 0.01), with increased CRS in the diets. Total DM intake and digestibility of DM, and digestibility of nutritional components were lower (P < 0.03) in WCS animals compared to supplemented animals, except for intake and digestibility of NDF, which was the opposite. Milk yield (MY) and fat corrected milk (FCM), as well as all milk components were unaffected (P > 0.05) by CRS inclusion. In contrast, MY, FCM, protein, lactose, casein, and non-fat milk solids (NFMS) were greater for animals that received supplementation (P < 0.05), compared to animals WCS. Milk fat and total dry extract (TMS) did not differ (P > 0.11) between two groups. In conclusion, CRS may be a potential corn meal replacer in the supplement of dairy cows under tropical conditions.

Supplementation of rumen-protected lysine during the close-up period improves vaginal discharge clearance in Holstein dairy cows.

We aimed to evaluate the effects of rumen-protected lysine (RPL) supplementation during the close-up period on uterine involution and the resumption of ovarian function in dairy cows. Fifty-two multiparous Holstein cows were categorized based on parity and expected calving date and randomly assigned to the RPL or control (CON) groups. The RPL group received 80 g of RPL daily from day 21 before the expected calving date until parturition. Blood samples were obtained twice weekly from pre-supplementation to 6 weeks postpartum. The onset of luteal activity postpartum was determined via ultrasonography twice weekly for up to 6 weeks postpartum. Uterine involution was tracked at 3 and 5 weeks postpartum through the vaginal discharge score, percentage of polymorphonuclear cells (PMN) in endometrial cytology samples, presence of intrauterine fluid, and gravid horn diameter via ultrasonography. Before supplementation, the RPL group showed amino acid imbalance, which was improved by RPL supplementation. There were no significant differences in the onset of luteal activity, percentage of PMN, intrauterine fluid, or the diameter of the uterine horn between the two groups. The vaginal discharge score in the RPL group decreased from 3 to 5 weeks postpartum, whereas that in the CON groups did not decrease. The number of cows with clinical endometritis was lower in the RPL group. Overall, RPL supplementation during the close-up period enhanced vaginal discharge clearance, potentially averting clinical endometritis, but did not affect the first ovulation in dairy cows.

Mineral patterns in hair: A decisive factor between reproducible and repeat breeder dairy cows.

Reproduction, especially impregnation, is a critical aspect of dairy cow management that directly influences herd milk productivity. We conducted a noninvasive hair mineral assay to compare the mineral profiles of two dairy cow groups: reproducible and repeat breeder, by investigating the levels of 11 essential minerals (Ca, Mg, Na, K, Fe, Cu, Mn, Zn, Cr, Se, and P) and 6 toxic elements (Hg, Pb, Cd, Al, As, and Ni) in both groups. We also conducted principal component and correlation matrix analyses to compare hair mineral patterns between the groups. Compared to their reproducible counterparts, repeat breeder cows had lower levels of Na, K, and Se. However, Fe, Cd, Al, and As levels were higher in repeat breeders than in their reproducible counterparts. The correlation matrix showed notable correlation patterns for each group. Ca, K, and Na levels were positively correlated in reproducible cows, whereas repeat breeder cows showed positive correlations only between Ca and K levels. Se showed positive correlations with Zn only in the reproducible cow group. Negative correlations were not found in the reproducible group, whereas the repeat breeder group exhibited 7 negative correlations. Despite the limitations of hair mineral analysis, this study provided useful insights into the reproductive potential of dairy cows. These findings aid in easing the prediction of repeat breeder occurrences in herds and are expected to facilitate timely mineral supplementation and other interventions to improve overall herd reproduction in dairy farms.

Effect of wet-aging on meat quality and exudate metabolome changes in different beef muscles.

The aim of this study was to evaluate meat quality and changes in the meat exudate metabolome of different beef muscles (5 d postmortem, longissimus lumborum and psoas major muscles) during wet-aging (additional 3, 7, 14, 21, and 28 d of aging). Shear force of meat declined significantly (P < 0.001) with aging, meanwhile, increased myofibril fragmentation index, lipid and protein oxidation with aging were observed (P < 0.01). Psoas major (PM) showed significantly higher (P < 0.05) purge loss, centrifugal loss, and cooking loss, as well as higher tenderness and more severe lipid and protein oxidation (P < 0.01) than longissimus lumborum (LL) during aging. Principal component analysis of the metabolomic profiles revealed distinct clusters according to the period of aging and the type of muscle simultaneously. Overabundant amino acids, peptides, oxidized fatty acids, and hydroxy fatty acids were found in long-term aged meat exudates, and forty metabolites were significantly correlated with meat quality characteristics. Fifty-nine metabolites were significantly affected by muscle type. These results demonstrated the potential possibility of evaluating meat quality using meat exudate metabolomics.

Green manure (Crotalaria juncea L.) enhances Origanum vulgare L. biomass accumulation, essential oil yield, and phytochemical properties.

Green manure (GM) may reduce the use of chemical fertilizers, been an ecologically appropriate strategy to cultivation of medicinal plants. Crotalaria juncea, is one of the most used because it adapts to different climatic and high nitrogen content. Origanum vulgare. is widely used in cooking, pharmaceutical, cosmetic industries and food products. The objectives of this study were to evaluate the GM on biomass, essential oil (EO), phenolic and antioxidant. The experiment consisted: control; 150, 300, 450, and 600 g (Sh= leaves+steam) more 200 g roots (R); 600 g aerial part; 200 g roots; and soil with 300 g cattle manure per pot. The highest dry weights were observed in the presence of GM and cattle manure (90 days). The control had an EO production 75% lower in relation to the dose of 450 g GM (Sh+R). Principal component analysis showed that GM and cattle manure positively influenced the dry weight, content, yield, and EO constituents, and total flavonoids. The GM contributed to the accumulation of the major EO compounds (trans-sabinene hydrate, thymol, terpinen-4-ol). The GM management may be beneficial for cultivating, because it can increase the production of biomass and the active components, in addition to being an inexpensive resource.

Non-encapsulated, encapsulated, and lyophilized probiotic Limosilactobacillus reuteri SW23 influenced the growth and gut health in calves.

The present study was conducted to assess the impact of non-encapsulated, air-dried microencapsulated, and lyophilized microencapsulated probiotics in indigenous cattle calves (Bos indicus). Twenty-four (5-7 days old) indigenous cattle calves were selected and assigned into four groups, with six calves in each as follows: control (CON), fed milk and basal diet alone, and treatment groups supplemented with non-encapsulated (NEC), air-dried microencapsulated (AEC) and lyophilized microencapsulated (LEC) probiotic L. reuteri SW23 at 108 CFU/head/day in skim milk as a carrier provided for 60 days. The animals were divided into four groups, adopting a complete randomized design, and the effects were considered significant at p ≤ 0.05. Probiotics supplementation increased (p < 0.05) body weight gain (kg), average daily gain, and structural growth measurements in calves of all treatment groups. Dry matter intake (g/d), feed conversion efficiency, and fecal counts of Lactobacilli and Bifidobacteria were also increased in the treatment groups compared to CON. The fecal consistency index was highest in CON (0.70 ± 0.03), followed by NEC (0.68 ± 0.01), AEC (0.66 ± 0.02), and LEC (0.65 ± 0.02). Fecal pH and ammonia levels were reduced (p < 0.05) in the probiotic-fed groups compared to CON, with a concomitant increase in fecal lactate, acetate, and propionate levels. In addition, cell-mediated and humoral immunity were significantly increased in supplemented groups as compared to CON. Thus, it can be concluded that supplementation of the probiotics in microencapsulated/non-encapsulated forms to neonatal calves had a variety of positive effects on their health, including better performance, improved gut health, and a lower fecal consistency index. Moreover, among all supplemented groups, the lyophilized microencapsulated group outperformed air-dried microencapsulated and non-microencapsulated groups in terms of ADG, DMI, and gut health.

Essential oil supplementation in milk replacers: short- and long-term impacts on feed efficiency, the faecal microbiota and the plasma metabolome in dairy calves.

Early supplementation with oregano essential oil (EO) in milk replacer (MR) may improve growth, immune responses, the microbiota and the metabolome in dairy calves during pre-weaning and in adulthood. Sixteen female dairy calves (3 days of age) were divided in two groups (n = 8/group): the control group (no EO) and the EO group (0.23 ml of EO in MR during 45 days). After weaning, calves were kept in a feedlot and fed ad libitum. The animals were weighed, and blood and faecal samples were collected on days 3 (T0), 45 (T1) and 370 (T2) to measure the biochemical profile and characterise peripheral blood mononuclear cells (PBMCs; CD4+, CD8+, CD14+, CD21+ and WC1+), the metabolome and microbiota composition. The EO group only had greater average daily weight gain during the suckling (EO supplementation) period (P = 0.030). The EO group showed higher average CD14+ population (monocytes) values, a lower abundance of Ruminococcaceae UCG-014, Faecalibacterium, Blautia and Alloprevotella and increased abundances of Allistipes and Akkermansia. The modification of some metabolites in plasma, such as butyric acid, 3-indole-propionic acid and succinic acid, particularly at T1, are consistent with intestinal microbiota changes. The data suggest that early EO supplementation increases feed efficiency only during the suckling period with notable changes in the microbiota and plasma metabolome; however, not all of these changes can be considered desirable from a gut health point of view. Additional research studies is required to demonstrate that EOs are a viable natural alternative to antibiotics for improving calf growth performance and health.

Trace mineral source and chromium propionate supplementation affect performance and carcass characteristics in feedlot steers.

Angus-crossbred steers (n = 400; 369.7 ±â€…7.6 kg) were used to determine the influence of trace mineral (TM) source and chromium propionate (Cr Prop) supplementation on performance, carcass characteristics, and ruminal and plasma variables in finishing steers. Steers were blocked by body weight (BW) and randomly assigned within block to treatments in a 2 × 2 factorial arrangement, with factors being: 1) TM source (STM or HTM) and 2) Cr supplementation (0 or 0.25 mg Cr/kg DM, -Cr or + Cr, respectively). Treatments consisted of the addition of: 1) sulfate TM (STM; 90, 40, and 18 mg/kg DM of Zn, Mn, and Cu, respectively), 2) STM and 0.25 mg Cr/kg DM from Cr Prop, 3) hydroxychloride TM (HTM; 90, 40, and 18 mg/kg DM of Zn, Mn, and Cu, respectively), and 4) HTM and 0.25 mg Cr/kg DM from Cr Prop. Each treatment consisted of 10 replicate pens with 10 steers per pen. Body weights were obtained on consecutive days at the initiation and termination of the 154-d study. Steers were fed a steam-flaked corn-based finishing diet. Ractopamine hydrochloride was fed for the last 31 d of the study. Ruminal fluid and blood samples were obtained from one steer per pen on days 28 and 84 for ruminal volatile fatty acids (VFA) and plasma TM and glucose analysis. Steers were slaughtered at the end of the study and individual carcass data were collected. No Cr × TM source interactions (P = 0.48) were detected. Steers supplemented with HTM had greater (P = 0.04) hot carcass weight (HCW), dressing percentage (DP), longissimus muscle (LM) area, and USDA yield grade (YG), and tended (P = 0.12) to have greater average daily gain (ADG) than those receiving STM. Average daily gain, gain:feed, dressing percentage, and longissimus muscle area were greater (P = 0.04) for + Cr steers compared to-Cr steers. Hot carcass weight tended (P = 0.06) to be greater for + Cr steers. Ruminal acetate concentrations at 28 d were lesser (P = 0.01) for HTM vs. STM steers, and greater (P = 0.04) for + Cr steers compared to-Cr steers. Plasma concentrations of Zn, Cu, and Mn were not affected by TM source or Cr supplementation. Steers supplemented with Cr had greater (P = 0.05) plasma glucose concentrations than-Cr steers at 28 but not at 84 d. Results of this study indicate replacing STM with HTM improved carcass characteristics in finishing steers, and Cr Prop supplementation improved steer performance and carcass characteristics.

Trace minerals (TM) are supplemented to finishing cattle diets to prevent TM deficiencies. Sources of TM differ in their bioavailability and effect on rumen fermentation. Chromium is a TM required in low concentrations to enhance insulin activity. We tested the effect of TM source (hydroxychloride; HTM vs. sulfate; STM) and supplemental Cr propionate (Cr Prop) on performance and carcass characteristics of finishing steers. Providing 0.25 mg of supplemental Cr/kg DM, from Cr Prop, improved gain, feed efficiency, and carcass characteristics in steers. Steers supplemented with HTM tended to gain faster and had improved carcass characteristics of economic importance compared to those supplemented with STM.

Preparation of high-temperature and low-temperature-resistant solid microbial agent for cattle manure fermentation and effect on composting.

We used microbiology and molecular biology techniques to screen out high-temperature and low-temperature-resistant saprobiotics for compost and prepared a compound fermentation bacteria agent to rapidly ferment cattle manure into high-quality organic fertilizer in low-temperature season. Conventional composting and high-throughput techniques were used to analyze the changes of physical and chemical indexes and biodiversity in the process of composting, from which high and low-temperature-resistant strains were obtained, and high-temperature and low-temperature-resistant solid composite bactericides were prepared and added to composting to verify the effects of composite bactericides on composting. The conventional composting cycle took 22 days, and the diversity of microflora increased first and then decreased. Composting temperature and microbial population were the key factors for the success or failure of composting. Two strains of high-temperature-resistant bacteria and six strains of low-temperature-resistant bacteria were screened out, and they were efficient in degrading starch, cellulose, and protein. The high-temperature and low-temperature-resistant solid bacterial agent was successfully prepared with adjuvant. The preparation could make the compost temperature rise quickly at low temperature, the high temperature lasted for a long time, the water content, C/N, and organic matter fell quickly, the contents of total phosphorus and total potassium were increased, and the seed germination index was significantly improved. Improve the composting effect. The solid composite bacterial agent can shorten the composting time at low temperature and improve the composting efficiency and quality.

1,25 dihydroxyvitamin D3-mediated effects on bovine innate immunity and on biofilm-forming Staphylococcus spp. isolated from cattle with mastitis.

Mastitis is one the most widespread and serious diseases in dairy cattle. Recurrent and chronic infections are often attributable to certain pathogenicity mechanisms in mastitis-causing pathogens such as Staphylococcus spp. These include growing in biofilm and invading cells, both of which make it possible to resist or evade antimicrobial therapies and the host's immune system. This study tested the effects of active vitamin D3 (i.e., calcitriol or 1,25-dihydroxyvitamin D3) on the internalization and phagocytosis of biofilm-forming Staphylococcus spp. isolated from animals with mastitis. Two established bovine cell lines were used: MAC-T (mammary epithelial cells) and BoMac (macrophages). Calcitriol (0-200 nM) did not affect the viability of MAC-T cells nor that of BoMac cells after 24 and 72 h. Concentrations of 0-100 mM for 24 h upregulated the expression of 24-hydroxylase in MAC-T cells, but did not alter that of VDR. Pre-treatment of the cells with calcitriol for 24 h decreased the internalization of S. aureus V329 into MAC-T cells (0-100 nM), and stimulated the phagocytosis of the same strain and of S. xylosus 4913 (0-10 nM). Calcitriol and two conditioned media, obtained by treating the cells with 25-200 nM of the metabolite for 24 h, were also assessed in terms of their antimicrobial and antibiofilm activity. Neither calcitriol by itself nor the conditioned media affected staphylococcal growth or biofilm formation (0-200 nM for 12 and 24 h, respectively). In contrast, the conditioned media (0-100 nM for 24 h) decreased the biomass of preformed non-aureus staphylococcal biofilms and killed the bacteria within them, without affecting metabolic activity. These effects may be mediated by reactive oxygen species and proteins with antimicrobial and/or antibiofilm activity. In short, calcitriol could make pathogens more accessible to antimicrobial therapies and enhance bacterial clearance by professional phagocytes. Moreover, it may modulate the host's endogenous defenses in the bovine udder and help combat preformed non-aureus staphylococcal biofilms (S. chromogenes 40, S. xylosus 4913, and/or S. haemolyticus 6). The findings confirm calcitriol's potential as an adjuvant to prevent and/or treat intramammary infections caused by Staphylococcus spp., which would in turn contribute to reducing antibiotic use on dairy farms.

Levodopa attenuates the feed intake reduction caused by ergot alkaloids in cattle.

Consumption of ergot alkaloids from endophyte-infected tall fescue results in losses to the livestock industry in many countries and a means to mitigate these losses is needed. The objective of this study was to evaluate intra-abomasal infusion of the dopamine precursor, levodopa (L-DOPA), on dopamine metabolism, feed intake, and serum metabolites of steers exposed to ergot alkaloids. Twelve Holstein steers (344.9 ±â€…9.48 kg) fitted with ruminal cannula were housed with a cycle of heat challenge during the daytime (32 °C) and thermoneutral at night (25 °C). The steers received a basal diet of alfalfa cubes containing equal amounts of tall fescue seed composed of a mixture of endophyte-free (E-) or endophyte-infected tall fescue seeds (E+) equivalent to 15 µg ergovaline/kg body weight (BW) for 9 d followed by intra-abomasal infusion of water (L-DOPA-) or levodopa (L-DOPA+; 2 mg/kg BW) for an additional 9 d. Afterward, the steers were pair-fed for 5 d to conduct a glucose tolerance test. The E+ treatment decreased (P = 0.005) prolactin by approximately 50%. However, prolactin increased (P = 0.050) with L-DOPA+. Steers receiving E+ decreased (P < 0.001) dry matter intake (DMI); however, when supplemented with L-DOPA+ the decrease in DMI was less severe (L-DOPA × E, P = 0.003). Also, L-DOPA+ infusion increased eating duration (L-DOPA × E, P = 0.012) when steers were receiving E+. The number of meals, meal duration, and intake rate were not affected (P > 0.05) by E+ or L-DOPA+. The L-DOPA+ infusion increased (P < 0.05) free L-DOPA, free dopamine, total L-DOPA, and total dopamine. Conversely, free epinephrine and free norepinephrine decreased (P < 0.05) with L-DOPA+. Total epinephrine and total norepinephrine were not affected (P > 0.05) by L-DOPA+. Ergot alkaloids did not affect (P > 0.05) circulating free or total L-DOPA, dopamine, or epinephrine. However, free and total norepinephrine decreased (P = 0.046) with E+. Glucose clearance rates at 15 to 30 min after glucose infusion increased with L-DOPA+ (P < 0.001), but not with E+ (P = 0.280). Administration of L-DOPA as an agonist therapy to treat fescue toxicosis provided a moderate increase in DMI and eating time and increased plasma glucose clearance for cattle dosed with E+ seed.

Fescue has become the dominant cool-season perennial grass in the southeastern region of the United States and is also found in other countries. Endophytes from a plant­fungus symbiotic relationship produce toxic alkaloids that have caused significant annual economic losses to the livestock industry. Treatments to alleviate this toxicosis are still demanded. This study evaluates the infusion of the dopamine precursor, levodopa (L-DOPA), to mitigate the toxicosis caused by ergot alkaloids. When L-DOPA was infused, eating duration increased and the decrease in feed intake caused by ergot alkaloids was less severe. Additionally, circulating dopamine and glucose clearance increased with L-DOPA. These results suggest that L-DOPA has the potential to aid in the mitigation of the toxicosis caused by ergot alkaloids.

Arbuscular mycorrhizal fungi, phosphorus and organic residues in Peltophorum dubium (Spreng.) Taub. seedlings.

Studies have underscored a growingdemand for innovative practices in the cultivation of seedlings from forest species, with a notable emphasis on the utilization of organic waste, inoculation with arbuscular mycorrhizal fungi (AMF), and phosphate fertilization. This study aimed to evaluate the impact of organic residues, inoculation with AMF, and phosphorus on the growth and quality of Peltophorum dubium (Spreng.) Taub. seedlings. Two independent experiments were conducted. In Experiment I, treatments included inoculation with various AMF species: control (without inoculation), Clareoideoglomus etunicatum, Rhizophagus heterosporum, Rhizophagus clarum, and MIX (a combination of the three AMF species), all in conjunction with varying doses of phosphorus (0, 60, 120, 180, and 240 mg kg-1 soil). In Experiment II, treatments comprised a control group (without AMF) and inoculation with Glomus clarum, Gigaspora margarita, Gigaspora albida, Clareoideoglomus etunicatum, and MIX (a combination of the four AMF species), each associated with four substrates: S1) soil + coarse sand - SCS, S2) SCS + poultry manure, S3) SCS + cattle manure, and S4) SCS + sheep manure. Peltophorum dubium seedlings exhibited heightened growth with the inoculation of R. heterosporum, R. clarum, and MIX. Positive responses were observed in seedlings when exposed to organic residues, particularly sheep manure, resulting in increased biomass production and enhanced Dickson quality index. The AMF inoculation, specifically with R. heterosporum, R. clarum, and MIX, provided optimal growth conditions for P. dubium seedlings. Remarkably, the utilization of organic residues, notably substrates with chicken manure and cattle manure, exerted substantial positive effects on both growth and quality of P. dubium seedlings.