Calving location preference and changes in lying and exploratory behavior of preparturient dairy cattle with access to pasture.

The objectives of this study were to (1) describe the calving location of dairy cattle given access to a pasture and barn; (2) identify factors associated with calving location; and (3) compare the lying and exploratory behavior of cows in the 24 h before calving and a previous day. Seventy-two Holstein dairy heifers and cows (n = 36 nulliparous and n = 36 primiparous and multiparous combined) were housed in a covered bedded-pack barn (167.4 m2) with free access to 2.1 ha of pasture. The composition of the group was dynamic, because cows were moved in weekly at 19 ± 6 d [mean ± standard deviation (SD)] before their calving date, and were removed immediately after calving. To facilitate data collection, we divided the environment into 9 sections, including the barn (section 1; 167.4 m2), 7 sections of open pasture (sections 2 to 8; 2,402 ± 60 m2), and 1 section of pasture surrounded by natural forage cover (section 9; 3,593 m2). We then collapsed these 9 sections into 3 distinct areas for further analysis: the barn, open pasture, and natural forage cover. Animals were fitted with accelerometers to measure lying time, lying bout duration, lying bouts, and steps for the 24 h before calving (calving day) and a similar 24 h period 4 to 11 d (median = 7) before calving (baseline day). We included parity (nulliparous vs. primiparous and multiparous) and heat stress [no heat stress = temperature-humidity index (THI) ≤68 vs. heat stress = THI >68 and ≤79] in all analyses; we included time of day and group composition as additional factors that may have affected calving location. We determined exploratory behavior using 10 min instantaneous scan sampling collected from video. At each scan, we recorded the section (1 to 9) the cow or heifer was located in, and then calculated the minimum number of sections that could be crossed between successive scans. Of the total sample, 39% calved in the barn, 26% calved in the open pasture, and 35% calved in the area with natural forage cover. Nulliparous heifers and those calving when heat stress was low (THI ≤68) selected the area with natural forage cover more frequently than the barn. On the calving day, cows spent more time lying down with more short bouts of lying, and crossed more sections compared with the baseline day. Steps were affected by an interactive effect of day, parity, and heat stress; nulliparous heifers took more steps on the calving day during conditions of heat stress compared with no heat stress. Results indicate that cows and heifers had different preferences for their environment at calving, and when provided access to pasture, both changed their lying and exploratory behavior on the day of calving compared with a previous day.

Influence of milk feeding levels and calf housing on subsequent performance of Holstein heifers.

The purpose of this study was to investigate the effects of increased milk feeding levels or social housing during the preweaning stage of Holstein dairy heifers on subsequent weight gain, health, and reproductive parameters over time. A total of 210 heifers were grouped by calving date in groups of 10 and randomly assigned to one of 3 treatments: low-milk individual housing (LMI; 4 L of milk/d), high-milk individual housing (HMI; 8 L of milk/d), or low-milk social housing (LMS; 4 L of milk/d). Data collected included passive transfer status, disease events, weight gain at different time periods, age at first calving, calving intervals, and milk yield over the first 3 lactations. Passive transfer was successful in 189 calves, and, overall, disease events were low in this herd. The average daily gain for heifers in the HMI group (0.79 ± 0.05 kg/d) was significantly higher (F 2, 9 = 4.76) during the preweaning treatment period compared with the other groups (LMI: 0.59 ± 0.05 kg/d; LMS: 0.68 ± 0.04 kg/d). Although treatment groups did not differ with respect to age at first calving, the LMS and HMI heifers calved (22 and 15 d, respectively) earlier than the LMI heifers. Milk yield over 3 lactations was similar among the treatment groups. This suggests that both nutrition and social dynamics can influence performance of preweaned calves. Further investigation is needed to understand the mechanisms driving increased weight gain in socially housed calves.

A four-season longitudinal study of enterohaemorrhagic Escherichia coli in beef cow-calf herds in Mississippi and Nebraska.

Our objective was to describe the probability of detecting seven serogroups of enterohaemorrhagic Escherichia coli (EHEC-7) of public health importance in faecal samples from beef cow-calf herds and to test for factors associated with their detection. Fresh faecal samples (n = 85) from two Mississippi and two Nebraska herds were collected in each of four seasons. Samples were tested for each EHEC-7 serogroup by a molecular screening assay. Separate management groups within herds were sampled, and group-level factors were recorded. To measure the effects of factors on faecal shedding of EHEC-7, separate multivariable logistic regression models were used, accounting for the random effect of clustering by group within farm. Statistical significance was set α = 0.05. Fifty-nine samples (4.3%) were positive for EHEC O26, and Nebraska samples were more likely to be positive than Mississippi samples (OR = 12.4, 95% CI: 1.1, 139.2). Forty-four samples (3.2%) were positive for EHEC O45. Odds for detection were greater in the summer than all other seasons combined (OR = 4.2, 95% CI: 1.3, 14.0), and odds decreased if a precipitation event occurred (OR = 0.07, 95% CI: 0.006, 0.8). EHEC O103 was detected in 66 samples (4.9%) with increased probability to be detected at increased temperature. EHEC O111 was detected in 71 samples (5.2%), and 43 samples (3.2%) were positive for EHEC O145. Both EHEC O111 and O145 were associated separately with season, with greater probability for detection in the summer. Eighteen (1.3%) and 68 (5.0%) samples were positive for EHEC O121 and EHEC O157, respectively. We failed to detect significant explanatory factors associated with probability to detect EHEC O121 or O157. Factors that vary by time and place, such as precipitation, ambient temperature, region and season, are uniquely associated with the probability to detect EHEC-7 in fresh faeces collected from cow-calf herds.

Cross-sectional study to estimate the prevalence of enterohaemorrhagic Escherichia coli on hides of market beef cows at harvest.

Cattle hides are an important source of enterohaemorrhagic Escherichia coli (EHEC) carcass contamination at slaughter. Seven EHEC serogroups are adulterants in raw, non-intact beef: EHEC O26, O45, O103, O111, O121, O145 and O157. The objective of this study was to estimate the probability for hide contamination with EHEC among US market beef cows at slaughter and to test the effects of season and geographic region on prevalence of hide contamination. Hides (n = 800) of market cows were swabbed at slaughter immediately after exsanguination, prior to hide removal. Cows were sampled from two geographically distinct beef packing plants during four seasons of 2015. Cattle source was categorized by northern or southern region. Samples were tested for EHEC by a molecular screening assay. The effects of region, season and their interaction on the probability of hide contamination by each EHEC serogroup were tested in separate multilevel multivariable logistic regression models, accounting for the random effect of clustering by plant. Statistical significance was set α = .05. Of 800 total samples, at least one EHEC was detected on 630 (79%) hides. Enterohaemorrhagic E. coli O26 was detected on 129 (16%) of all hides sampled, EHEC O45 on 437 (55%), EHEC O103 on 289 (36%), EHEC O111 on 189 (24%), EHEC O121 on 140 (18%), EHEC O145 on 171 (21%) and EHEC O157 on 89 (11%). Detection of EHEC O26 and EHEC O121 was associated with season. Season and region were associated with detecting EHEC O45 and EHEC O157. Season-by-region interactions were associated with the outcome of detecting EHEC O103, EHEC O111 and EHEC O145. Season, region of origin and the interaction of these factors affect hide contamination of market beef cattle at slaughter by EHEC, and each serogroup responds to these factors uniquely.

A randomized controlled trial to evaluate the effects of dietary fibre from distillers grains on enterohemorrhagic Escherichia coli detection from the rectoanal mucosa and hides of feedlot steers.

Feeding high levels (≥40% dry matter) of distillers grains may increase the risk for cattle to carry enterohemorrhagic Escherichia coli (EHEC) O157. The mechanism for the increased risk is not known nor whether non-O157 EHEC are similarly affected. Our objective was to test whether the fibre content or other components of modified distillers grains plus solubles (MDGS) affects the probability for cattle to carry EHEC serogroups of public health importance. A 2 × 2 plus 1 factorial treatment arrangement within a randomized block design was utilized. Within each of four blocks, 25 feedlot pens (n = 8 steers/pen) were assigned randomly to (i) corn-based control diet; (ii) 20% dry matter (DM) MDGS; (iii) 40% DM MDGS; (iv) corn bran added to corn-based diet to match fibre of 20% MDGS or (v) 40% MDGS. Rectoanal mucosa swabs (RAMS) were collected on day (d)0, d35, d70 and d105; hide swabs were collected on the last feeding day. Samples were tested for EHEC by a molecular screening assay. The effects of fibre source and fibre level on EHEC carriage were tested using multilevel logistic regression (generalized linear mixed models; α = 0.05). EHEC O45 RAMS detection was associated with fibre level, source and sampling day. EHEC O103 RAMS detection increased by feeding 40% MDGS but not the corresponding corn bran diet. Hide contamination by EHEC O45 or O103 was less likely in cattle fed MDGS compared to corn bran diets. EHEC O111 RAMS detection decreased by feeding 40% MDGS but not by feeding the corresponding corn bran diet. Detection of EHEC O157 or O145 was not associated with dietary factors. Feeding 40% MDGS increased the probability for carriage of some EHEC serogroups but decreased probability of others, which indicated that EHEC serogroups have different risk factors associated with feeding MDGS and little association with dietary fibre.

Comparison of the ribonucleoproteins of different rabies virus serotypes by radioimmunoassay.

Radioimmunoassay (RIA) provides a sensitive serological procedure for detecting rabies virus ribonucleoprotein (RNP) as well as its specific antibodies, RIA was carried out using highly purified RNPs labelled by the chloramine-T method. This paper describes optimal conditions for iodination of RNP with high specific activity. The optimal concentrations of 125I, RNP, chloramine-T, and reducing agent as well as the effect of pH on the reaction were investigated. RIA proved to be extremely sensitive for detection of homologous antibodies. In competition experiments the part-relationship of the group-specific RNPs of the three rabies virus serotypes (HEP, MOK and LBV) was confirmed.

Tramadol hydrochloride: analgesic efficacy compared with codeine, aspirin with codeine, and placebo after dental extraction.

Tramadol hydrochloride is a novel, centrally acting analgesic with two complementary mechanisms of action: opioid and aminergic. Relative to codeine, tramadol has similar analgesic properties but may have fewer constipating, euphoric, and respiratory depressant effects. A two-center randomized double-blind controlled clinical trial was performed to assess the analgesic efficacy and reported side effects of tramadol 100 mg, tramadol 50 mg, codeine 60 mg, aspirin (ASA) 650 mg with codeine 60 mg, and placebo. Using a third molar extraction pain model, 200 healthy subjects were enrolled in a 6-hour evaluation after a single dose of drug. Of the 200 patients enrolled, seven provided incomplete efficacy data or discontinued prematurely and one was lost to follow-up. Using standard measures of analgesia, including total pain relief score (TOTPAR), maximum pain relief score (MaxPAR), sum of pain intensity difference scores (SPID), peak pain intensity difference (Peak PID), remedication, and global evaluations, all active treatments were found to be numerically superior to placebo. ASA/codeine was found to be statistically superior to placebo for all measures of efficacy. Tramadol 100 mg was statistically superior to placebo for TOTPAR, SPID, and time of remedication, whereas tramadol 50 mg was statistically superior to placebo onlyfor remedication time. Codeine was not found to be statistically superior to placebo for any efficacy measure. A greater TOTPAR response compared with all other active measures was seen for ASA/codeine during the first 3 hours of study. The 6-hour TOTPAR scores for the tramadol groups and ASA/ codeine group were not significantly different. Gastrointestinal side effects (nausea, dysphagia, vomiting) were reported more frequently with tramadol 100 mg, ASA/ codeine, and codeine 60 mg than with placebo.

Antigenic variants of rabies virus.

Monoclonal antibodies directed either against the nucleocapsid or the glycoprotein of rabies virus were reacted by indirect immunofluorescence and mouse neutralization tests with vaccine strains and rabies field isolates of various origin. Major antigenic determinants allow the grouping of viruses and minor ones the differentiation of virus strains. A protection study showed the existence in nature of certain antigenic variants against which conventional vaccines do not fully protect. The isolation of two such variants from 'imported' bats in the Federal Republic of Germany is reported here for the first time.

The effects of topical steroidal and systemic nonsteroidal anti-inflammatory drugs on experimental gingivitis in man.

Retrospective studies in man and prospective studies in animals have indicated that systemically administered anti-inflammatory drugs may decrease plaque-induced inflammation and loss of attachment. The purpose of the present double blind study was to determine the effects of a systemically administered nonsteroidal anti-inflammatory drug and a topically applied steroidal anti-inflammatory drug on experimentally produced gingivitis. Eighteen dental students were brought to a state of optimal gingival health and then divided into three groups. One group received placebo gel to apply topically and placebo capsules. A second group received placebo gel and capsules containing sulindac, a nonsteroidal anti-inflammatory drug. The third group received a topical steroidal gel and placebo capsules. All subjects refrained from home care for 22 days in the maxillary right quadrant. Results of the study indicate that the topical steroidal drug significantly inhibited gingival inflammation while the systemically administered nonsteroidal drug had no apparent effect.

Medication usage and dental caries outcome-related variables in HIV/AIDS patients.

The purpose of this study was to access current medication usage by HIV/AIDS patients and its effects on dental caries and on unstimulated salivary flow rates. Thirty females and 127 males (mean age = 39.6 +/- 7.4 years), of whom 46% were White/Non-Hispanic, 39% African-American, and 15% Hispanic, were examined and interviewed at the Bering Dental Clinic, Houston, Texas. The mean time in years after seroconversion was 5.4 +/- 4.1. Calibrated examiners performed dental caries examination (DMFS) with dental explorers and bitewing radiographs. Interviews were carried out with pretested questionnaires, and medication usage was assessed by illustrative examples of HIV/AIDS medications. Salivary flow rates were determined gravimetrically (mL/min). Bivariate analysis and analysis of variance (ANOVA) were used to analyze the data. Because there were no race or gender effects on dental caries outcome variables or salivary flow rates, separate logistic regression models for medication usage were generated, which were adjusted for age and CD4+ cell counts. Patients who, currently, were receiving antiretroviral therapy (ART) had a lower occurrence of dental caries than patients not taking these medications. An unexpected finding in the lower caries rate group was a decrease in salivary flow rates, which was a probable oral side effect of ART. It appears from this cross-sectional study that systemic medication for the management of HIV disease has no significant detrimental effect on the dentition.

Unstimulated salivary flow rates of young children.

OBJECTIVE: Studies on salivary flow rates in human beings have mainly been carried out with adults. The purpose of this study was to determine the unstimulated salivary flow rates of children 4 to 7 years old. In addition, the relative contributions of the variables age, gender, race, height, body weight, dentition status, use of prescription medication, and health status (information obtained from parents) to the unstimulated salivary flow rates of children were also studied. STUDY DESIGN: Data were obtained from children (n = 447) at 2 sites in the United States (site 1, southeast Michigan; site 2, northern Michigan) and at 5 sites in Brazil (site 3, Porto Alegre; site 4, São Paulo; site 5, Belém; and sites 6 and 7, sites in Rio de Janeiro). In northern Michigan (site 2) the participants were cognitively or developmentally disabled, or both. In Rio de Janeiro (site 7), a group of 8- to 12-year-olds served as a control group. Saliva samples were collected for 3 minutes between 9 AM and noon in the spring or summer, and the saliva rate was determined gravimetrically. Data were analyzed by analysis of variance, bivariate analysis, and regression analysis. RESULTS: The secretion rates at the 7 sites were (in milliliters per minute) 0.19 +/- 0.15, 0.23 +/- 0.28, 0.34 +/- 0.23, 0.48 +/- 0.37, 0.25 +/- 0.27, 0.37 +/- 0.28, and 0.61 +/- 0.34, respectively. There were significant differences among sites (P <.0001). The older group (site 7) had flow rates that were significantly higher than the flow rates of any other group. In addition, children from Michigan (sites 1 and 2) had significantly lower rates than most groups of children in Brazil. Girls had lower unstimulated salivary flow rates than boys did at all the sites, but the differences were not statistically significant. Race was shown not to affect the flow rates. The use of any prescription medication by children in the previous 3 months was associated with lower salivary flow rates than were found in children not using prescription medication. Children who were in good health and who had no previous medical conditions had higher flow rates--but not significantly so. Higher flow rates occurred in children with mixed dentition than in children with primary dentition, although again the differences were not statistically significant. Regression analysis revealed weight to be of significance in explaining the variability of the unstimulated salivary flow rates at 2 sites, height at 1 site, the use of prescription medication at 2 sites, and age at 1 site. CONCLUSIONS: The unstimulated salivary flow rates in children in the northern United States are comparable with those reported for Japanese children, whereas the flow rates of children in Brazil are comparable with those reported for North American and European adults. In addition, none of the demographic variables/parameters tested contributed consistently to the variability of the unstimulated salivary flow rates in children at the 7 sites assessed in this study.

Oral vaccination of raccoons (Procyon lotor) with an attenuated (SAD-B19) rabies virus vaccine.

Unlike previous reports to the contrary, raccoons (Procyon lotor) were successfully vaccinated against rabies with a liquid SAD-B19 attenuated virus vaccine administered per os and given in vaccine-laden baits. There was neither evidence of vaccine-induced rabies in raccoons nor in a limited safety trial with opossums (Didelphis virginiana) given SAD-B19. Protection from lethal street rabies virus infection was not absolute: only three of nine raccoons given 1 x 10(6.0) TCID/ml were protected versus five of 10 raccoons given 1 x 10(7.0) TCID/ml of SAD-B19 and challenged 4 mo after consumption of vaccine-laden baits. Six of eight raccoons consuming 1 x 10(8.8) TCID/ml of SAD-B19 vaccine in baits survived street rabies virus challenge 2 mo postvaccination. Raccoon survivorship was not wholly dependent upon rabies virus-neutralizing antibody titer on the day of challenge. Vaccinated raccoons demonstrated a prominent anamnestic response within 1 wk following challenge. Surviving raccoons were observed for a minimum of 3 mo following street rabies virus challenge with neither clinical nor pathologic evidence of rabies. The SAD-B19 rabies vaccine administered within baits in captivity appears less effective for raccoons than for its demonstrated efficacy in the immunization of free-ranging foxes (Vulpes vulpes) in Europe.

Ineffectiveness and comparative pathogenicity of attenuated rabies virus vaccines for the striped skunk (Mephitis mephitis).

Three attenuated rabies virus vaccines (SAD-B19, ERA/BHK-21, AZA 2) were compared for efficacy and safety in the striped skunk (Mephitis mephitis) by the oral and intranasal routes. The SAD-B19 and ERA/BHK-21 vaccines were given orally; all three vaccines were given intranasally. Oral administration of SAD-B19 and ERA/BHK-21 vaccines induced neither seroconversion nor significant protection against rabies challenge. One skunk which consumed a SAD-B19 vaccine-laden bait succumbed to vaccine-induced rabies. Intranasal instillation of the three vaccines resulted in the deaths of two of six (AZA 2), three of six (ERA/BHK-21) and six of six (SAD-B19) skunks.

A model for clinical evaluation of the effect of antimicrobial agents on carious dentin.

PURPOSE: To evaluate, longitudinally, the effect of a chlorhexidine varnish on the proteolytic activity of dentin caries in vivo. MATERIALS AND METHODS: 20 permanent molars and 8 primary molars with carious lesions in dentin were studied in subjects 18-35 yrs old (n=20), and 5-6 yrs old (n=8) respectively. These lesions were clinically evaluated according to texture and color. Carious dentin specimens were obtained by means of biopsies performed with a #4 carbide bur at the initial visit (TO) before application of a 10% chlorhexidine varnish and 2, 4, 8, and 12 wks thereafter. The dentin biopsies were immersed in Sorensen's buffer, vortexed for 30 s, and mixed with a 1.67 mM solution of n-benzoyl-DL-arginine-naphthylamide (BANA), a substrate for proteolytic enzymes. Samples were incubated overnight at 37 degrees C and color was developed with 0.1% fast garnet. The optical density (OD) of reaction mixtures was recorded photometrically. All teeth were grouped for analysis, as Mann-Whitney tests revealed no statistically significant differences between median values for OD for both age groups. ANOVA was used to compare progressive inhibition of proteolytic activity in dentin caries samples over time. RESULTS: The average proteolytic activity at the dentin substrates (OD) at TO and 2, 4, 8 and 12 wks thereafter were 0.794+/-0.089, 0.741+/-0.071, 0.676+/-0.087, 0.600+/-0.094, and 0.508+/-0.108 respectively. The chlorhexidine varnish mediated a significant inhibition of the proteolytic activity present in dentin caries after 12 wks (P<0.0001). At T0, 100% of the carious lesions examined were characterized as soft upon exploration. After 12 wks, 54% (15/28) of the lesions were partially hardened and 46% (13/28) hardened/nonprogressing. The dentin color was yellow/light brown in 100% of the lesions at baseline, and dark brown/black in 86% (24/28) after 12 wks. CLINICAL SIGNIFICANCE: This study demonstrated that chlorhexidine varnishes arrested active caries in vivo and inhibited the proteolytic activity present in these lesions. These findings strengthen the rationale for including chlorhexidine in the overall treatment strategy for patients with high caries activity.

Preliminary report on the effects of propolis on wound healing in the dental pulp.

The purpose of this investigation was to determine the antimicrobial and healing potential of propolis on direct dental pulp exposures. This study used 25 adult male rats. Pulp exposures were performed and animals were allocated to propolis and calcium hydroxide (Ca(OH)2 groups. Animals were killed on days 5, 7, 10, and 14. The teeth were routinely processed for histological evaluation. Non-parametric tests were employed to analyze the data. No significant differences were found between study groups on the wound healing of the dental pulp. Both substances were comparable in exhibiting normal reorganization of the pulp and no increased vascularity, and were equally efficacious in maintaining a low inflammatory and microbial cell population as well as in stimulating the formation of reparative dentin.

Causes of abnormal vaginal bleeding in a Family Practice Center.

Abnormal vaginal bleeding had an incidence of 20.0 per 1,000 woman-years in patients of the Kanawha Valley Family Practice Center. Contraception-related bleeding was the most common cause, accounting for 28 percent of the cases. Anovulatory and dysfunctional uterine bleeding were the next most common causes, accounting for 15 percent and 13 percent, respectively. All three causes were uncommon in women aged 41 to 55 years, and absent in women older than 55 years. Perimenopausal bleeding, the dominant cause of abnormal vaginal bleeding in the 41-to-55-year group, was also absent in women older than 55 years of age. In women 56 years of age or older, endometrial carcinoma caused 28.6 percent of the bleeding; it did not occur in any other group.