Behavior and performance of lactating sows and piglets reared indoors or outdoors.

Two hundred eighty-seven lactating Newsham sows and their litters were used to determine the effects of intensive indoor (n = 147) and intensive outdoor (n = 140) production systems on sow and litter productivity and behavior. All sows were of contemporary age and fed a completely balanced sorghum-based diet. Behavior data were collected by live observation on 40 sows and litters (20 indoor and 20 outdoor) using a 5-min scan sample over a 4-h period in the afternoon (1400 to 1800). The durations of lying (90.0 vs 72.1 +/- 2.76% of time observed) and drinking (4.42 vs 1.41 +/- 0.6% of time observed) were higher (P < 0.01) among indoor than among outdoor lactating sows. Nursing interval and feeding and sitting behaviors were not different (P > 0.05) between production systems. Piglets spent more (P < 0.05) time walking (10.1 vs 5.2 +/- 1.72% of time observed) and engaged in play activity (5.0 vs 1.7 +/- 1.26% of time observed) when housed outdoors than indoors. Outdoor piglets had more (P < 0.05) nursing behaviors directed toward the sow (27.5 vs 20.3 +/- 2.02% of time observed) but time spent in contact with the sow did not differ between environments (38.8 vs 39.2 +/- 2.78% of time observed). Treatments did not influence (P > 0.05) any of the sow or piglet production parameters. In conclusion, outdoor-kept Newsham sows and their piglets showed a richer behavioral repertoire, but the diverse environments did not influence production parameters.

Tail-docking alters fly numbers, fly-avoidance behaviors, and cleanliness, but not physiological measures.

Tail docking is an animal well-being issue not only regarding the docking procedures but also because of concerns during fly season. To address the latter question, we selected eight cows that had been tail-docked in a previous experiment and eight nondocked cows matched by stage of lactation. Physiological, immunological, and behavioral measures were used to evaluate the well being of those cows housed in a tie-stall barn during fly season for 5 consecutive days. Behavior was observed for 5-min interval instantaneous scan samples for 1 h each at 0800, 1200, and 1600 h. Flies were counted before behavior observations. Blood samples were taken daily for plasma and leukocyte separation. Cows were scored on d 5 for cleanliness on a five-point scale. Docked cows were cleaner, but fly counts of docked cows were greater for total fly counts and rear leg counts. However, counts were not different on front legs. Time of day was significant, so each time of day was analyzed separately. Docked cows were observed to exhibit fewer tail swings at 0800 h, but docked cows tended to ruminate more at that time. Docked cows tended to stand less at the 1200 h observation. Total fly-avoidance behaviors were greater for all cows at the 1600-h observation. Only tail swings tended to be more frequent with docked cows, but foot stomps occurred only in the docked cows. Lymphocyte phenotypes, acute-phase proteins, and immunoglobulin concentrations did not differ. In conclusion, although docked cows were cleaner, as the fly numbers increase throughout the day, fly-avoidance behaviors also increased and foot stomping appeared as an alternative method for fly avoidance by docked cows.

Behavioral sampling techniques for feedlot cattle.

Continuous observations are an accurate method for behavioral measurements but are difficult to conduct on large numbers of animals because of extensive labor requirements. Thus, we sought to develop methods of behavioral data collection in feedlot cattle production systems that reasonably approximated continuous sampling. Standing, lying, feeding, drinking, and walking behaviors were examined from 224 h of continuous video from 64 heifers. Experiment 1 (n = 24 heifers) compared continuous behavioral sampling techniques (Continuous) with scan sampling using intervals of 1, 5, 10, 15, 30, and 60 min and time sampling (a technique for the periodic recording of behavior) for the first 10 min out of every 60 min. Means for each scan sampling method did not differ in estimated percentage of duration of behaviors (P > 0.05) from continuous sampling, except for scan sampling with a 60-min interval. Scan sampling with a 60-min interval differed from more frequent scan sampling intervals for all behaviors except lying. Scan sampling with short intervals (1 and 5 min) was correlated highly with Continuous for all behaviors. The longer the scan interval, the lower the correlations, especially for behaviors with short duration. Time sampling was not an accurate technique for measuring the sampled behaviors. Focal animal sampling (using continuous sampling of individuals) indicated that one heifer was representative of the entire pen of 10 animals (Continuous) for all maintenance behaviors except drinking. Scan sampling methods (1-, 5-, 10-, and 15-min intervals) were accurate methods of behavioral sampling for feedlot cattle, but scan intervals of 30 or 60 min were less accurate and less precise. Time sampling was not an accurate method because it overestimated standing and underestimated lying behaviors. Experiment 2 (n = 40 heifers) investigated the number of focal animals required to accurately represent continuous behavioral sampling for all animals. Focal animal sampling was accurate for most behaviors using as few as 1 animal out of 10 but was not an accurate method for drinking behavior unless 40% of the animals in the pen were observed. Estimates of sample sizes needed for experimental protocols are provided. Behavioral means, standard deviations, and coefficients of variation are presented along with estimates of required sample sizes. These results validate accurate, precise, and efficient methods for quantifying feedlot cattle behavior.

Tail-docking influences on behavioral, immunological, and endocrine responses in dairy heifers.

Behavioral and physiological changes were measured following tail-docking in primiparous heifers. One month before projected first parturition, 21 heifers were assigned to control (nondocked), docked, or docked with lidocaine groups. Heifers were banded to initiate tail-docking and the necrotic tail was removed after 144 h. Physiological, immunological, and behavioral measures were taken for 240 h following banding. Cortisol was not different for control and treated heifers. Haptoglobin increased for docked heifers by 168 h postbanding (24 h postdocking). Alpha1-acid glycoprotein decreased as haptoglobin increased, and alpha1-acid glycoprotein increased until 240 h postbanding. Tumor necrosis factor-alpha increased only with lidocaine and did not show an effect of docking by 240 h postbanding. Lymphocyte phenotyping demonstrated increased CD4+ and CD8+ peripheral blood mononuclear cells for docked plus lidocaine heifers and gammadelta+ cells of those heifers tended to be reduced compared with docked heifers. Eating was the only maintenance behavior affected by banding in both docked groups (increased with banding and decreased with docking). The initial banding procedure did not alter heifer physiology and altered only eating behavior, but the cutting of the tail (docking) increased haptoglobin in response to the tissue damage and returned eating behavior to baseline. The use of lidocaine to anesthetize the tail before banding affected lymphocyte phenotypes and TNF-alpha (banding alone did not alter these parameters).

Heat and social stress effects on pig immune measures.

Forty-eight domestic pigs were used to evaluate the effects of heat and social stress on immune indices. Pigs were brought together in groups of three per pen and video-taped for the first 72 h. Video tapes were viewed to determine time spent in aggressive and submissive behaviors. Social status of each pig was determined from outcomes of agonistic interactions. Pens of pigs were housed in either a thermoneural (control, 24 degrees C) or heat-stress (33 degrees C) air temperature. Immune measures were determined from blood samples obtained on d 0, 7, 14, 21, and 28 after grouping. Social status had an effect (P < .05) on lymphocyte proliferation in response to pokeweed mitogen: socially intermediate pigs had a higher proliferative response than socially dominant or subordinate pigs. Many immune measures showed a significant interaction between heat and social stress over days of the study. Generally, socially dominant or submissive pigs had alterations in immune function (elevated numbers of neutrophils, decreased antibody production) compared with socially intermediate pigs. In conclusion, heat and social stress interact in their effect on the pig's immune system. Although one might have predicted immunosuppression among submissive pigs, there also seemed to be immunological costs to dominant pigs as well. These data also have implications in design of stressor research in that social behavior should be measured or controlled.

Consequences of restraint stress on natural killer cell activity, behavior, and hormone levels in rhesus macaques (Macaca mulatta).

Three experiments were performed to determine the effect of stress on the neuroendocrine-immune system in nonhuman primates. In Experiment 1 the diurnal variation in cell and hormone levels was determined. The percentages of neutrophils, monocytes, and eosinophils fluctuated throughout the 24-hr period, while white blood cell (WBC), neutrophil-to-lymphocyte ratio (N:L), hemoglobin (Hgb), natural killer cell cytotoxicity (NK activity) and beta-endorphin levels did not. Experiment 2 investigated the effects of ketamine and restraint on behavior. Scratching was increased in control monkeys and animals receiving ketamine, whereas passivity was increased in chair-restrained animals. In Experiment 3, eight adult male rhesus monkeys were restrained in primate chairs at 0600h. Behavior was filmed for 3 hr and blood samples were collected at 0700, 0800, and 0900. Whole blood was analyzed for total WBC and percentage of each leukocyte type. NK activity was also measured. Plasma levels of cortisol and beta-endorphin were determined and behavior was quantitated from video-records. WBC and the percentage of neutrophils increased during the restraint period, while the percent lymphocytes and monocytes decreased. NK activity also decreased over time after restraint whereas plasma cortisol and beta-endorphin levels increased significantly. Although after the 3 hr of restraint stress, changes were found in hormone levels, behavior, and NK activity, there were no significant correlations between the parameters measured. Thus, our results indicate that there is not a common neuroendocrine response or single neuroendocrine mediator that results in predictable behavioral changes and immune suppression following stress.

Immunosuppression in mice induced by cold water stress.

A number of studies indicate that stress can result in suppression of the immune system in animals and man. Most of the studies have focused on alterations of lymphocyte function while only a few have investigated alterations of macrophage function or macrophage cytokine production. Macrophages play an essential role in homeostasis of the immune response. Indeed, the earliest events of the immune response occur in cells of the monocytic lineage, and their secretion of various cytokines may have both immunological and nonimmunological effects. The present studies were undertaken to determine whether alterations in macrophage physiology occur in mice subjected to a stress stimulus. Our studies in mice exposed to cold water stress for 4 days indicated reduced numbers of thymocytes and splenocytes, decreased T-cell blastogenesis, and reduced NK activity. Examination of elicited peritoneal macrophages from stressed mice revealed increased prostaglandin E2 (PGE2) secretion and decreased immune region associated antigen (Ia) expression in response to interferon-gamma. Despite elevated PGE2 levels, indomethacin was generally unable to restore depressed immune function. Of special interest was the finding that cell-associated and secreted interleukin 1 were significantly higher from unstimulated elicited macrophages from stressed mice. These results suggest that early in the response to stress, functions of a variety of cells within the immune system, especially macrophages, are altered and that dysregulated macrophage function may well contribute to the generalized suppression of the immune response in cold water stressed mice.