Effects of pellet starch levels in automatic milking systems on rumen fermentation, plasma metabolites, and milk production in mid-lactation cows.

The aim of this study was to evaluate whether the starch levels in pellets fed to cows in automatic milking systems (AMS) affect subacute ruminal acidosis (SARA) occurrence and metabolite parameters. Twenty-four lactating cows (124.4 ± 49.9 days in milk) were studied in a crossover design with two periods of 21 days each and two treatment groups-a control group fed AMS pellets containing 30.0% of starch dry matter (DM) and an experimental group fed AMS pellets containing 23.5% of starch DM. All cows received the same partial mixed ration (PMR). The 1-hr mean ruminal pH in both groups decreased over 4 hr after feeding on PMR but recovered by the next morning. The ruminal pH was unaffected by either treatment, and both groups developed SARA. The groups had no significant differences in the concentrations of ruminal volatile fatty acids, lipopolysaccharides, plasma acute-phase proteins, other metabolites, and hormones. The milk yield and composition were not different in both groups. Feeding low-starch pellets in the AMS did not contribute to the risk of SARA occurrence in cows and had no additive effects on rumen fermentation, plasma metabolites, or milk production.

Developing models to predict feces and urine excretion in Japanese Black fattening steer by multiple regression analysis.

The objective of this study was to develop models for predicting the amount of feces and urine excreted by Japanese Black fattening steer using a dataset of 119 digestion trials for a total of 46 animals. Correlation analysis was used to analyze the relationships between feces and urine excretion and feed intake, feed digestibility, and nitrogen balance. Multiple regression analysis was conducted to develop models for predicting the amount of feces and urine excreted using the explanatory variables selected from various animal and dietary parameters based on P-value (<0.10) and variance inflation factor (<3.0). Resultingly, dry matter intake was a primary predictor of feces excreted. The prediction equation for the amount of feces excretion as a function of body weight, dry matter intake, and calculated total digestible nutrients fits the data well (adjusted coefficient of determination [adj R2 ] = 0.519, root mean square error = 1.57). Furthermore, the nitrogen content in the urine was the primary predictor of the urine excretion amount. Thus, the prediction equation for the amount of urine excreted using the nitrogen content in urine yielded a highly accurate model (adj R2 = 0.813, root mean square error = 4.12).

Effects of crude protein and neutral detergent fiber percentages in the diet of Japanese Black steers on rumen fluid properties, blood biochemical properties, and carcass characteristics.

The effects of crude protein (CP) and neutral detergent fiber (NDF) percentages in the diet of Japanese Black steers on rumen fluid properties, blood biochemical properties, and carcass characteristics were examined. Twelve 13-month-old Japanese Black steers were used for this study and slaughtered at 30 months of age. Steers were assigned to a control group (n = 6) and test group (n = 6) and were fed a concentrate containing 12.9%-13.9% CP and 26.5%-29.8% NDF or 9.1%-9.6% CP and 29.9%-31.2% NDF, respectively. Lipopolysaccharide activity levels in rumen fluid were lower in the test group than in the control group. Plasma urea nitrogen concentration and activities of aspartate aminotransferase and γ-glutamyltransferase remained lower in the test group than in the control group. In contrast, plasma vitamin A concentrations remained higher in the test group than in the control group. Carcass characteristics did not significantly differ between the two groups. These results suggest that dietary CP and NDF percentages in feed for Japanese Black steers older than 13 months of age affected rumen fluid properties and blood biochemical properties, indicating a reduced load on the liver with a small effect on carcass characteristics.

Effect of anti-lipopolysaccharide of Escherichia coli antibody feeding for Holstein calves on ruminal lipopolysaccharide activity and plasma metabolites concentrations during pre- and post-weaning periods.

This study was performed to examine the effects of anti- lipopolysaccharide (LPS) of Escherichia coli chicken egg Yolk immunoglobulin (IgY) provided to calves for 7 weeks during the pre- and post-weaning periods on rumen LPS activity, plasma acute phase protein (APP) concentrations, and metabolic parameters. A total of 30 Holstein calves were randomly assigned to two groups of 15 each: an IgY group fed Anti-E. coli LPS IgY, and a control group fed whole egg powder as a placebo. The study was conducted on calves aged 3-10 weeks, weaned at 7 weeks. The ruminal LPS activity of the IgY group was approximately 60% lower than the control group at 10 weeks of age. Plasma APP and cytokine concentrations in the IgY group did not differ from those in the control group. The daily weight gain in the IgY group was significantly higher than the control group for the whole experimental period. Plasma albumin/globulin was lower (P<0.05), and plasma aspartate transferase concentration was higher (P<0.05) in the IgY group than in the control group during the experimental period. In conclusion, feeding Anti-E. coli LPS IgY for 7 weeks pre- and post-weaning remarkably reduced the rumen LPS activity and improved the daily weight gain. The impact of Anti-E. coli LPS IgY on LPS activities in the lower gastrointestinal tract, and elucidation as to the mechanism responsible for the improvement in daily weight gain require further investigation.

Predicted functional analysis of rumen microbiota suggested the underlying mechanisms of the postpartum subacute ruminal acidosis in Holstein cows.

BACKGROUND: The relationships between the postpartum subacute ruminal acidosis (SARA) occurrence and predicted bacterial functions during the periparturient period are still not clear in Holstein cows. OBJECTIVES: The present study was performed to investigate the alterations of rumen fermentation, bacterial community structure, and predicted bacterial functional pathways in Holstein cows. METHODS: Holstein cows were divided into the SARA (n = 6) or non-SARA (n = 4) groups, depending on whether they developed SARA during the first 2 weeks after parturition. Reticulo-ruminal pH was measured continuously during the study period. Reticulo-ruminal fluid samples were collected 3 weeks prepartum, and 2 and 6 weeks postpartum, and blood samples were collected 3 weeks before, 0, 2, 4 and 6 weeks postpartum. RESULTS: The postpartum decline in 7-day mean reticulo-ruminal pH was more severe and longer-lasting in the SARA group compared with the non-SARA group. Changes in predicted functional pathways were identified in the SARA group. A significant upregulation of pathway "PWY-6383" associated with Mycobacteriaceae species was identified at 3 weeks after parturition in the SARA group. Significantly identified pathways involved in denitrification (DENITRIFICATION-PWY and PWY-7084), detoxification of reactive oxygen and nitrogen species (PWY1G-0), and starch degradation (PWY-622) in the SARA group were downregulated. CONCLUSIONS: The postpartum SARA occurrence is likely related to the predicted functions of rumen bacterial community rather than the alterations of rumen fermentation or fluid bacterial community structure. Therefore, our result suggests the underlying mechanisms, namely functional adaptation of bacterial community, causing postpartum SARA in Holstein cows during the periparturient period.

Effects of feeding wood kraft pulp silage containing sweet-potato shochu distillery by-product on feed intake, feed digestibility, rumen fermentation, blood components, and growth performance in Japanese Black fattening steers during early period.

The effects of long-term feeding of wood kraft pulp (KP) silage containing sweet-potato shochu distillery by-product (SDP) on feed intake, feed digestibility, rumen fermentation, and growth performance of Japanese Black steers were investigated during the early fattening period. Ten Japanese Black steers (9.8 ± 0.6 months of age) were used in this study. Five steers (KP group) were fed KP silage as a replacement for 10% timothy hay (dry matter bases), in contrast to the other five (control group). KP silage consisted of 92.9% KP and 7.1% SDP (dry matter bases). The experiment was conducted for 18 weeks. No significant differences were observed in terms of feed intake, feed digestibility, or daily body weight gain between the groups. In addition, diurnal changes in the rumen pH and ruminal lipopolysaccharide activity did not differ between the groups. However, the plasma concentration of aspartate transaminase in the KP group was slightly lower (P = 0.078) than that in the control group. Thus, our study suggested that feeding KP silage does not reduce feed intake or affect the rumen fermentation or growth performance of Japanese Black fattening steer.

Effects of wood kraft pulp as a partial replacement for roughage on rumen fermentation and productivity in dairy cows.

In this study, we evaluated the partial replacement of roughage with wood kraft pulp (KP) on rumen fermentation and productivity of dairy cows. Eighteen cows were divided into control and KP groups. The KP group started adaptation to KP 3 weeks before calving; after calving, they were fed a total mixed ration for 12 weeks, wherein 18% Timothy hay was replaced with KP. The dry matter intake, body weight, and milk yield and composition were similar in the control and KP groups. The average daily rumen pH was higher with KP feeding, and the average daily ruminal temperature remained lower at 16 days after calving (P < 0.05). The concentration of volatile fatty acids remained unaltered, the molar proportion of acetic acid decreased, and the molar proportion of propionic acid increased, indicating a low acetic acid:propionic acid ratio (P < 0.05). Lipopolysaccharide activity in the rumen fluid was higher in the KP group (P < 0.05); however, the rumen microbiota were unaffected. The digestibility of dry matter and neutral detergent fiber increased 12 weeks after calving, whereas excretion of urinary nitrogen decreased (P < 0.05). Partial replacement of roughage with KP did not suppress rumen fermentation and maintained postpartum productivity.

Effects of wood kraft pulp feeding on feed digestibility and rumen fermentation of Japanese Black steer in the middle fattening stage.

We investigated the effects of wood kraft pulp (KP) feeding on feed digestibility and rumen fermentation of Japanese Black (JB) steer in the middle fattening stage. The feeding experiment was carried out a replicated 3 × 3 Latin square design using six JB steers (16.2 ± 0.8 months of age). Steers were fed rice straw and three concentrated feeds: commercial formula feed (control), formula feed containing 7.5% KP on a dry matter (DM) basis (7.5% KP), and formula feed containing 15% KP on a DM basis (15% KP). Feed digestibility and rumen fermentation parameters were recorded for 3 days during the measurement period, after an adaptation phase of 11 days. There was no significant difference in DM intake per day among diets. A slightly higher digestibility of neutral detergent fiber was observed in steers fed 15% KP, compared with those fed other diets (P = 0.059). The butyric acid ratio in rumen fluid was higher in steers fed KP diets than in steers fed control (P = 0.083). The average ruminal pH was unaffected by KP diets. This study suggests that replacing 15% of concentrated feed with KP has little effect on feed digestibility and rumen fermentation in JB fattening steer.

Liver transcriptome response to periparturient hormonal and metabolic changes depends on the postpartum occurrence of subacute ruminal acidosis in Holstein cows.

We investigated changes in rumen fermentation, peripheral blood metabolites and hormones, and hepatic transcriptomic dynamics in Holstein cows with and those without subacute ruminal acidosis (SARA) during the periparturient period. Sixteen multiparous Holstein cows were categorized in the SARA (n = 8) or non-SARA (n = 8) groups depending on whether they developed SARA during the 2 wk after parturition. Reticulo-ruminal pH was measured continuously throughout the study. Rumen fluid, blood, and liver tissue samples were collected at 3 wk prepartum and 2 and 6 wk postpartum, with an additional blood sample collected at 0 and 4 wk postpartum. The 1-h mean pH was depressed postpartum in both groups, whereas depression was more severe in the SARA group simultaneously with significantly longer duration of time (for pH <5.6 and 5.8). Significant expression of differentially expressed genes in liver tissue (DEGs; false discovery rate corrected P < 0.1) were identified only in the non-SARA group and were further analyzed by Ingenuity Pathway Analysis software. Among the top expressed DEGs, the hepatic genes encoding lipid and cholesterol secretion (APOA1, APOA4, and G0S2) and gluconeogenesis (PC, G6PC, and PCK1) were upregulated postpartum. In silico analysis revealed the significant postpartum activation of upstream regulators, such as INSR, PPARG, and PPARGC1A. These results suggested that hepatic transcriptomic responsiveness to postpartum metabolic load and hormones were likely discouraged in cows with SARA when compared with the significant activation of genes and signaling pathways for adequate metabolic adaption to postpartum high-grain diet feeding in Holstein cows without SARA.

Anti-lipopolysaccharide antibody mitigates ruminal lipopolysaccharide release without acute-phase inflammation or liver transcriptomic responses in Holstein bulls.

Anti-lipopolysaccharide (LPS) antibody administration has the potential benefits of neutralizing and consequently controlling rumen-derived LPS during subacute ruminal acidosis. Four Holstein bulls were used in this crossover study with a 2-week wash-out period. Anti-LPS antibody (0 or 4 g) was administered once daily for 14 days. Significantly lower ruminal LPS and higher 1-h mean ruminal pH were identified in the 4 g group. However, blood metabolites, acute-phase proteins, cytokines, and hepatic transcriptomes were not different between the two groups. Therefore, anti-LPS antibody administration mitigated ruminal LPS release and pH depression without accompanying responses in acute-phase inflammation or hepatic transcriptomic expression.

Anti-lipopolysaccharide antibody administration mitigates ruminal lipopolysaccharide release and depression of ruminal pH during subacute ruminal acidosis challenge in Holstein bull cattle.

The effects of anti-lipopolysaccharide (LPS) antibody on rumen fermentation and LPS activity were investigated during subacute ruminal acidosis (SARA) challenge. Eleven Holstein cattle (164 ± 14 kg) were used in a 3 × 3 Latin square design. Cattle were fed a roughage diet on days -11 to -1 (pre-challenge) and day 2 (post-challenge), and a high-grain diet on days 0 and 1 (SARA challenge). For 14 days, 0-, 2-, or 4-g of anti-LPS antibody was administered once daily through a rumen fistula. Ruminal pH was measured continuously, and rumen fluid and blood samples were collected on days -1, 0, 1, and 2. Significantly lower ruminal LPS activity on day 1 was observed in the 2- and 4-g groups than those in the 0-g group. In addition, significantly higher 1-hr mean ruminal pH on SARA challenge period (days 0 and 1) was identified in the 4-g group than in the 0-g group. However, rumen fermentation measurements (total 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 depression without the depression of rumen fermentation and peripheral blood metabolites during SARA challenge in Holstein cattle.

Effects of grazing adaptation on intake, ruminal fermentation, blood metabolites, and body weight change in dairy cows after turning out to pasture in early spring.

This study investigated the effect of adaptation to grazing in early spring on herbage intake, ruminal fermentation parameters, blood metabolite concentrations, and body weight change in dairy cows. The experiment was conducted on eight rumen-cannulated non-lactating cows in the early spring period. Four cows were adapted to grazing by stocking for 4 hr for 1 week (ADP group). The other cows were kept in a barn during the period (CON group). Then, both groups of cows were stocked together throughout a day on a 1 ha pasture for 3 weeks (experimental period). In the first week of the experimental period, compared to the CON group, the ADP group had a higher herbage intake, ruminal NH3 -N and total VFA concentration, and blood urea concentration, but the NEFA concentration was lower in the ADP group (p < .01). During the subsequent weeks, there were little differences in ruminal fermentation parameters and blood metabolites. Cows in the ADP group maintained their body weight, but cows in the CON group lost 60 kg of body weight in the first week of the experimental period.

Changes in peripheral blood oxidative stress markers and hepatic gene expression related to oxidative stress in Holstein cows with and without subacute ruminal acidosis during the periparturient period.

We investigated changes in peripheral blood metabolites, oxidative stress markers (malondialdehyde, potential antioxidant capacity, and glutathione peroxidase [GPX]), and hepatic gene expression related to oxidative stress in Holstein cows with and without subacute ruminal acidosis (SARA) during the periparturient period. Eighteen multiparous Holstein cows were categorized into SARA (n=9) or non-SARA (n=9) groups depending on whether they developed SARA; reticulo-ruminal pH was <5.6 for more than 3 hr per day, during the 2 weeks after parturition. Blood and liver tissue samples were collected 3 weeks prepartum and 2 and 6 weeks postpartum, with an additional blood sample collected 0 and 4 weeks postpartum. Blood aspartate transaminase (AST) and nonesterified fatty acid (NEFA) increased significantly (P<0.05) after parturition in both groups. GPX activity decreased gradually after parturition in the SARA group. In the SARA group, gene expression of GPX 1 and microsomal glutathione S-transferase 3 (MGST3) decreased significantly (P<0.05), and expression of metallothionein 2A increased significantly (P<0.05) after parturition in the SARA group. Superoxide dismutase 1 and MGST3 decreased significantly (P<0.05) 2 weeks postpartum in the non-SARA group. Gene expression related to oxidative stress was negatively correlated with AST, NEFA and total ketone body levels. Therefore, the hepatic gene expression related to oxidative stress might change associated with a negative energy balance, and might relate the high oxidative stress in the SARA group during periparturient period.

Cluster analysis to evaluate disease risk in periparturient dairy cattle.

Predicting periparturient disease risk is of immense value to the dairy industry. Periparturient diseases are interrelated with each other; however, predicting the onset risk of these diseases has predominantly been based on a single blood parameter for a single disease. This study examined a new diagnostic method to predict the risk of periparturient diseases. We conducted cluster analysis of multiple blood constituents from 20 Holstein cattle at 1 week post-partum, and the cattle were divided into two groups, A or B. We then compared the periparturient and early-lactation blood constituents of these groups. Group B had significantly higher 3-hydroxybutyric acid concentrations and were suspected to have subclinical ketosis. Group B also had significantly lower calcium concentrations, with a tendency for subclinical hypocalcemia. We also performed discriminant analysis using blood parameters at 1 week post-partum, which grouped the population into the same two groups as the cluster analysis based on three variables: inorganic phosphorus, calcium, and either phospholipids or total cholesterol. We further showed that these discriminant functions could be used to predict the risk of periparturient disease even before parturition. Our results indicate that cluster analysis with multiple blood constituents is useful for predicting periparturient disease risks.

Effects of Saccharomyces cerevisiae supplementation on growth performance, plasma metabolites and hormones, and rumen fermentation in Holstein calves during pre- and post-weaning periods.

This study aimed to evaluate the effects of supplementing Saccharomyces cerevisiae (SC) during the pre- and post-weaning periods on growth, metabolic and hormonal responses, and rumen fermentation in calves. Three-week-old Holstein calves were assigned to either control (n = 12) or SC group (n = 12), the latter of which received 2 × 109  cfu/day of SC. The experiment was conducted over a period of 7 weeks around weaning. Daily gain (DG) in the SC group was higher (p < .05) than that in the control group. In the SC group, plasma glucose, insulin, and growth hormone (GH) concentrations were higher (p < .05) and concentrations of glucagon and insulin-like growth factor 1 (IGF-1) tended to be higher (p < .1) than in the control group. Proportion of rumen propionate and concentration of rumen ammonia nitrogen at 10 weeks of age were greater (p < .05) in the SC group than that in the control group. Supplementation of SC around weaning may improve dietary nutrient and energy availability and increase plasma GH and IGF-1 concentrations. These changes observed in SC-supplemented calves could be closely related to the improvement of DG.

Notice of RETRACTION: Changes in rumen fermentation, bacterial community, and predicted functional pathway in Holstein cows with and without subacute ruminal acidosis during the periparturient period.

The authors have elected to retract this paper in accordance with the following points. The article as written contains misleading information and omits important details. Cows in this study were assigned to groups based on the current definition of subacute ruminal acidosis; they were housed on two different farms and fed two different sets of rations in this study. However, multiple farms were not described in the materials and methods and this was not accounted for in the statistical analysis as published. The diets shown in Table 1 were not actually fed to animals; rather, the proportions of ingredients listed represent an average of the two farms housing the cows. The authors regret the errors.

Exposure to blue LED light before the onset of darkness under a long-day photoperiod alters melatonin secretion, feeding behaviour and growth in female dairy calves.

The effect of blue LED on melatonin secretion, feeding behaviour and growth was addressed in Holstein female dairy calves. In Exp.1, six animals (8 weeks old, 97 ± 4.1 kg BW) were exposed to yellow or blue LED for 2 hr before darkness over 7 days under a long-day photoperiod (LDPP). In Exp. 2, six animals (8 weeks old, 88.5 ± 4.8 kg BW) were exposed to blue light from a white LED all daytime or a yellow LED for 2 hr before the darkness of LDPP (blue light cut) over 3 weeks. In Exp. 1, blue light mildly suppressed melatonin secretion during the 2-hr treatment but did not affect the timing of the nightly melatonin rise. However, the rise in nighty melatonin levels was higher with yellow than blue LED. In Exp. 2, white LED completely suppressed melatonin secretion during the 2-hr treatment, but plasma melatonin concentrations were similar during the darkness. Grass hay intake, rumination time, frequency of water intake and body weight gain were higher in animals exposed to the yellow rather than the white LED. Overall results indicate that exposure to blue light from white LEDs under an LDPP suppresses melatonin secretion and might negatively impact the development of female dairy calves.

Provision of beta-glucan prebiotics (cellooligosaccharides and kraft pulp) to calves from pre- to post-weaning period on pasture.

We conducted two feeding experiments to evaluate the effects of supplementation with either cellooligosaccharide or kraft pulp on growth performance in grazing beef calves (Japanese Black) from 4 weeks pre-weaning to 12 to 16 weeks post-weaning. In Experiment 1 (20-week duration), nine calves (2.9-month-old females) were assigned to either a control group (CON) or an experimental group (CEL) fed cellooligosaccharide at a rate of 10 g/day mixed with concentrate. Average daily weight gain tended to be greater in CEL than in CON, especially after 1 month of weaning. In Experiment 2 (16-week duration), 10 calves (2.0-month-old females) were assigned to either a control group or an experimental group (KRA) fed kraft pulp at a rate of 10% replacement of total digestible nutrients with concentrate. The proportion of fibrolytic bacteria increased and that of methanogenic Archaea decreased in the rumen microbial community composition of KRA calves in Experiment 2, whereas the decrease in Fibrobacter and Archaea was observed in CEL calves at first 4 weeks in Experiment 1. We conclude that beta-glucan prebiotic supplementation to grazing calves at pre-weaning would affect rumen microbial composition and modified rumen fermentation characteristics, leading to a better rumen environment via different means.

Theoretical turnover rate of the rumen liquid fraction in dairy cows and its relationship to feed intake, rumen fermentation, and milk production.

Ruminant animals are able to convert plant materials (grain and the human-indigestible portion of carbohydrates) to milk and meat. In this conversion, most of the plant materials are digested by rumen fermentation and are changed to short-chain fatty acids, microbial cells, and methane, which is released into the atmosphere. The relationships among feed, rumen fermentation, and milk production are poorly understood. Here we report a novel indicator of characteristics of rumen fermentation, theoretical turnover rate (TTOR) of the rumen liquid fraction. The TTOR was calculated from the presumed rumen volume (PRV) which is estimated by dividing the methane yield by the methane concentration of rumen fluid. The formula for the TTOR is: TTOR = PRV/body weight0.75 . Our present analyses confirm that the TTOR as an indicator is capable of connecting feed, rumen fermentation, and milk production, because dry matter intake/TTOR showed a strong correlation with milk yield/TTOR. In addition, the TTOR may be related to ruminal pH, as we observed that the ruminal pH decreased as the TTOR increased. We propose that the TTOR is a factor characterizing rumen fermentation and a good indicator of the productivity of ruminants and dysbiosis of the rumen microbiome.