However, higher acidity caused by a high-grain diet, as seen in ruminal acidosis or SARA, decreases the proportion of due to death or lysis of gram-negative bacteria, resulting in higher LPS activity in the rumen [1, 20]. group. However, rumen fermentation measurements (total Tinoridine hydrochloride volatile fatty acid [VFA], VFA components, NH3-N and lactic acid) and peripheral blood metabolites (glucose, free fatty acid, beta-hydroxybutyrate, total cholesterol, blood urea nitrogen, aspartate aminotransferase and gamma-glutamyl transferase) were not different among the groups during the experimental periods. Therefore, anti-LPS antibody administration mitigates LPS release and pH depressive disorder without the depressive disorder of rumen fermentation and peripheral blood metabolites during SARA challenge in Holstein cattle. reduced the decrease in ruminal pH in Holstein calves fed a high-concentrate diet [16]. In addition, active dried supplementation in calves produce more butyric and lactic acids as energy source during ruminal acidosis challenge [20]. Although probiotic or microbial supplementations may improve rumen fermentation, they were not able to entirely prevent the occurrence of SARA. Furthermore, strategies for controlling free ruminal lipopolysaccharide (LPS) have not been considered extensively. In the cattle rumen, the bacterial community under the high-forage diet is composed of an approximately one-to-one ratio of and at a phylum level [11, 14]. However, higher acidity caused by a high-grain diet, as seen in ruminal acidosis or SARA, decreases the proportion of due to death or lysis of gram-negative bacteria, resulting in higher LPS activity in the rumen [1, 20]. Consequently, increased ruminal Rabbit Polyclonal to GIMAP5 LPS can translocate to Tinoridine hydrochloride the blood-stream, triggering inflammatory [9] and acute-phase protein responses [4] in cattle. However, LPS bound to lipoproteins is usually removed from circulation by liver hepatocytes [7]. Therefore, LPS neutralization and related functions of liver cells are important in cattle fed a high-grain diet. Previously, studies using LPS-binding peptides to neutralize LPS were performed using the phage display method [12] and peptide-bound beads [18], and studies were performed with mice [3, 22]. However, to the best of our knowledge, no research on anti-LPS antibody administration has been conducted in cattle despite the potential benefits of neutralizing and controlling Tinoridine hydrochloride rumen-induced LPS. Therefore, we investigated the effects of ruminal anti-LPS antibody administration on rumen fermentation and LPS activity during SARA challenge. We hypothesized that the use of an anti-LPS antibody in cattle fed a high-grain diet might mitigate the adverse effects of rumen-derived LPS activity. MATERIALS AND METHODS Anti-LPS antibody preparation The anti-LPS antibody was produced under patented and proprietary procedures (EW Nutrition Japan., Gifu, Japan) as described elsewhere [23]. Briefly, the vaccine made up of 1 ml of antigen (1 109 colony forming unit/g of inactivated whole O139) with oil adjuvant was injected intramuscularly into egg-laying hens (Hy-Line W36), and the second injection was performed 8 weeks after the first injection. After the 2 weeks after the second injection, eggs were collected and stored at 4C. The separated egg yolk from the collection was homogenized thoroughly, filtered to eliminate other components, and spray-dried (140 to 72C) to prepare the product in a powder form. The result was 1 g of the product bound to 0.25 g of purified LPS from O111 as tested by in house ELISA method using the anti-O111:B4 LPS rabbit IgG capture antibody, anti-O111:B4 LPS guinea pig IgG primary antibody, and horseradish peroxidase conjugated anti-guinea pig IgG secondary antibody. We decided the amount of anti-LPS antibody based on the previously reported ruminal LPS concentration (up to 5 g/ml) in growing Holstein steers (330 to 380 kg body weight) with approximately 100 l of rumen [13]. Animals and experimental design The experimental protocol was approved by the Iwate University Laboratory Animal Care and Use Committee (A201453-1; Morioka, Japan). Eleven fistulated Holstein bull cattle (5C6 months of age) were used in a 3 3 Latin square design without a wash-out period. Cattle were fed a roughage (orchard and timothy mixed hay; 5.6C7.0 kg/day) diet during the first 11 days (days ?11 to ?1; pre-challenge), a high-grain (50% concentrate and 50% soybean flakes; 3.0C3.6 and 3.0C3.8 kg/day, respectively) diet for 2 days (days 0 and 1; SARA challenge), and then a roughage diet for 1 day (day 2; post-challenge) (Table 1). The cattle were administered 0 (control group), 2, or 4 g immunoglobulin yolk made up of the anti-LPS antibody (EW Nutrition Japan) per head once daily through the rumen fistula for 14 consecutive days. The Tinoridine hydrochloride diets were supplied daily at 0800 hr and 1630 hr in two equal.