Body temperature of dry cows on pasture: environmental and behavioral effects

To investigate interrelations among factors potentially affecting body temperature, we observed body temperature, activity, and relative aggregation of 3 to 5 dry cows from a herd of 12 to 15 every 20 min. Ambient conditions were noted every 1 h and fly counts every 3 h. Observations during daylight for 5 d with and without shade indicated effects of shade were minimal and were extended to 24 h without shade at six weekly intervals. Cows lie down during the evening, grazed near sunrise and sunset, and alternated standing and grazing during the day. The aggregation index was greatest during periods of standing and least during grazing; however, it remained constant across periods of similar activity. Cows shifted activity from grazing to standing during periods of increased fly activity. Ambient temperatures ranging from 13 to 35 degrees C had little influence on measured variables. Body temperatures showed one to three daily dips (greater than 1 degree C) and a hysteresis pattern. Almost all dips were associated with transitions from lying to grazing. Body temperature was constant in the morning, rose to a higher level in the afternoon, and remained high until the next morning.     

Optimal fluorescence excitation and emission bands for detection of fecal contamination

Fecal contamination of food products is a critical health issue. To test the feasibility of the use fluorescent techniques to detect fecal contamination, fluorescence excitation and emission characteristics of fecal matter from cows, deer, swine, chickens, and turkeys in the UV to far-red regions of the spectrum were evaluated. To allow the optimization of the detection of fecal contamination on animal carcasses and cut meats, emission-excitation spectra of the feces were compared with spectra for animal meats. The feedstuffs for the swine, chickens, and turkeys were also analyzed. Excitation at approximately 410 to 420 nm yielded the highest level of fluorescence for both feces and feedstuffs. Emission maxima were in the red region (at 632 nm for chicken feces and at 675 nm for the feces of the other species). The major constituent responsible for emission at 632 nm was tentatively identified as protoporphyrin IX; emission at 675 nm most likely emanates from chlorophyll a or its metabolites. Animal meats emitted strong fluorescence in the blue-green regions, but no emission peaks were observed in the red region for these meats. These results suggest that fluorescence emissions from naturally occurring chlorophyll a and its metabolites are good markers for fecal contamination and that with excitation at 410 to 420 nm, the responses of fecal matter can easily be differentiated from the responses of animal meats. We suggest that the detection of fecal contamination can be enhanced by requiring a minimum chlorophyll a content in the finishing diets of all farm animals.     

Level of aspiration risk-taking behavior, and projective test performance: A search for coherence.

37 student nurses performed in tasks that have served as criteria for differentiating persons with internal vs. external control expectancies. Correlations were obtained between level of aspiration, gambling, and projective test variables. While the obtained relationships with the Internal-External Control of Reinforcement scale were negligible, the relationships among performance variables were pronounced. 2 distinctive response patterns were observed and labeled task-inappropriate and task-appropriate responding. Achievement-oriented behaviors in the level of aspiration task and in the gambling task were related to each other, and both were related to the adequacy of response to sexual stimuli in projective testing. (19 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of presence of calf on milking-induced release of prolactin and oxytocin during early lactation of dairy cows

The ability of dairy cows to release either prolactin or oxytocin in response to machine milking in a conventional milking parlor was reduced among cows maintained with their calves during the 1st wk postpartum. However, presence of the calf caused no prolonged inhibition; cows evaluated 9 or 23 days after calf removal released similar quantities of prolactin and oxytocin after milking compared to controls (cows whose calves were removed within 24 h after parturition) at the same stage of lactation. Ambient temperature on the day of sampling was positively associated with the premilking serum prolactin concentration among cows housed with or without their calves (correlation coefficients were .52 and .59), but neither ambient temperature nor premilking serum prolactin concentrations were closely associated with area under milking-induced prolactin response curves (correlation coefficients from -.15 to .18). Unlike basal serum prolactin concentration, ambient temperature on the day of sampling was not closely associated with premilking serum concentrations of oxytocin or quantities released to the milking stimulus (correlation coefficients from -.19 to -.12). These results confirm that the calf can inhibit maternal secretion of prolactin and oxytocin in the dairy cow. These data also indicate that the capacity of the cow to respond to the milking stimulus is independent of premilking serum concentrations of prolactin or oxytocin. Better understanding of factors that regulate the secretion of these hormones at milking may allow development of techniques to enhance hormonal response to milking stimuli and possibly enhance milk production.     

Internal versus external control of reinforcement: A review.

A summary of research concerning the construct, internal vs. external control of reinforcement, is presented. Investigations with this variable have utilized situational manipulations of locus of control or have involved differential predictions to given situations based on measures of the internal-external control dimension. In both types of investigation, locus of control is found predictive to different social behaviors, learning performances, and to more and less achievement-related activities. Suggestions for further areas of study are presented. (2 p. ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Locus of control as a modifier of the relationship between stressors and moods.

In the search for moderators of negative life events, locus of control (LOC) has been thought to be one of the more potentially important personality variables. Recent research has substantiated this hypothesis to a limited degree. The present 3 experiments with 216 undergraduates presents stronger indications for the utility of variables. LOC measures (Rotter's Internal–External LOC Scale) interacted with recalled negative life events in predicting mood states that were assessed weekly over a period of several weeks. Multiple regression analyses indicated that negative life events that had occurred during the high school years had a lingering effect on the current mood states of the more external Ss. On the other hand, more recent negative life events resulted in mood disturbances for all Ss regardless of LOC scores, although externals were equally distraught in the absence of negative events. Multiple correlations between negative life events, LOC, and mood scores attained sizable magnitudes. Positive life events, on the other hand, had relatively slight effects on subsequent mood disturbance. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Detection of fecal contamination on apples with nanosecond-scale time-resolved imaging of laser-induced fluorescence

Detection of apples contaminated with feces is a public health concern. We found that time-resolved imaging of apples artificially contaminated with feces allowed optimization of timing parameters for detection. Dairy feces were applied to Red Delicious and Golden Delicious apples. Laser-induced fluorescence responses were imaged by use of a gated intensified camera. We developed algorithms to automatically detect contamination iteratively by using one half of the apples and validated them by applying the optimized algorithms to the remaining apples. Results show that consideration of the timing of fluorescence responses to pulsed-laser excitation can enhance detection of feces on apples.     

Need for approval and threatened negative evaluation as determinants of expressiveness in a projective test.

Constriction, or the lack of expressiveness in projective testing as measured by the number of human movement responses given to the Barron inkblot test, was predicted on the basis of 133 undergraduate Ss' need for approval and expectancy of possible disapproval which derived from E's directions. Results strongly supported the emphasis upon situation cues and personal motives as predictors of responses to projective testing. Additional findings with repression-sensitization and the CPI Good Impression scale complimented the findings with need for approval. Constriction was most evident when tests offered personal threat but this was especially so for high need for approval persons seeking to make good impressions. (21 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Method to monitor the precision of milk yields recorded at individual milking stalls on daily basis.

Automated systems to record individual milk weights of cows at each milking are now common on dairy farms. These data are used by Dairy Herd Improvement Association (DHIA) for testing purposes and by farmers to monitor herd performance. Despite the importance of these data, little effort has been made to monitor the function and reliability of milking stalls and recording equipment on a daily basis. Described is an algorithm that allows for continuous monitoring of the function of individual milking stalls. The basis of the algorithm is the comparison of milk yield of individual cows over a period of days. For each cow, milk production at a selected stall is compared with production of that same cow when milked at any other stall. These ratios are averaged across all cows milked at least once in the selected stall and once at any other stall. Ideally, the mean ratio for each stall should be 1. Stalls where the mean ratio deviates from 1 by more than 5% are assumed to be malfunctioning. This algorithm was implemented as a computer program and was used to identify 3 malfunctioning stalls out of 12 at the USDA dairy facility (Beltsville, MD). The algorithm can easily be incorporated into existing management programs or used as a separate program. In either case, routine use of this algorithm can improve the reliability of DHIA test programs and potentially reduce the incidence of new mastitis infections by enabling detection of malfunctioning milking equipment.     

Comparison of models to identify lame cows based on gait and lesion scores, and limb movement variables

Bovine lameness results in pain and suffering in cattle and economic loss for producers. A system for automatically detecting lame cows was developed recently that measures vertical force components attributable to individual limbs. These measurements can be used to calculate a number of limb movement variables. The objective of this investigation was to explore whether gait scores, lesion scores, or combined gait and lesion scores were more effectively captured by a set of 5 limb movement variables. A set of 700 hind limb examinations was used to create gait-based, lesion-based, and combined (gait- and lesion-based) models. Logistic regression models were constructed using 1, 2, or 3 d of measurements. Resulting models were tested on cows not used in modeling. The accuracy of lesion-score models was superior to that of gait-score models; lesion-based models generated greater values of areas under the receiving operating characteristic curves (range 0.75 to 0.84) and lower mean-squared errors (0.13 to 0.16) compared with corresponding values for the gait-based models (0.63 to 0.73 and 0.26 to 0.31 for receiving operating characteristic and mean-squared errors, respectively). These results indicate that further model development and investigation could generate automated and objective methods of lameness detection in dairy cattle.