Effects of 2 wintering practices on behavioral and physiological indicators of welfare of nonlactating, pregnant dairy cattle in a pasture-based system.

In countries with pasture-based dairy systems and relatively cold winters, such as New Zealand, it is common to manage pregnant, nonlactating cows on forage crop paddocks rather than pasture, due to slow pasture growth rates. Wintering dairy cattle on grazed crops can compromise welfare if wet and muddy underfoot conditions occur, which can reduce lying. This study investigated behavioral and physiological indicators of welfare of cows under 2 wintering practices: cows managed on and grazed kale crop (Brassica oleracea), and cows managed on pasture with baled hay. Following dry-off (d 0), 80 cows were randomly assigned to 1 of the 2 wintering practices (40 cows/practice) and monitored between d 4 and 32 (phase 1). During this period, lying and stepping behavior was continuously recorded using leg-based accelerometers. Blood samples were obtained at d 0 and 32 for measurements of thyroxine (T4), nonesterified fatty acids (NEFA), white blood cells (WBC), and red blood cells. All data for phase 1 were presented descriptively due to the lack of treatment replication. Daily mean air temperature during this period was 5.2°C (range: 0.0-10.7°C), and rainfall was 1.1 mm/d (range: 0-5.6mm/d). Between d 4 and 32, cows in both groups spent similar amounts of time lying (pasture with hay cows: 8.9 h/24 h ± 2.57, kale crop cows: 8.7 h/24 h ± 3.06, mean ± SEM). Both groups reduced their lying on wet and cold days, and there was evidence of rebound lying once unfavorable weather conditions stopped. Cows on kale crop had numerically higher NEFA and lower WBC compared with cows managed on pasture, although most physiological values were within normal ranges. In a second phase of the study (d 34 and 35), cows were managed under controlled, replicated conditions in the 2 wintering practices using typical on-farm stocking rates (2 or 4 cows per group in the pasture with hay and kale crop treatments, respectively; n = 10 groups/treatment). During this period, cow behavior, skin and surface temperatures, hygiene scores, feed intakes, and ground conditions were measured. Weather conditions during the 48-h exposure were mostly cold and dry (mean air temperature: 7.8°C, range: -2.2 to 20.5°C). Cows managed on pasture with hay spent more time lying down on the first day of exposure; however, this was likely due to less space being available to kale cows on this day. Cows managed on pasture with hay ruminated more than cows on kale crop on both days of observations (d 1: 37.9% vs. 30.9% of observations, d 2: 36.8% vs. 28.7% of observations for pasture with hay and kale crop groups, respectively) and were lying more often in postures indicative of greater thermal comfort. Cows managed on pasture with hay had higher skin and surface temperatures compared with cows on kale crop, whereas cows on kale crop had dirtier coats. Results suggest that opportunities for thermal comfort were greater for cows managed on pasture with hay bales, which may be due to increased rumination activities and more insulated lying areas.

Immunohistochemical and ultrastructural features of congenital melanocytic naevus cells support a stem-cell phenotype.

BACKGROUND: Multiple congenital melanocytic naevi (CMN) in one individual are caused by somatic mosaicism for NRAS mutations; however, the lineage of the mutated cells remains uncertain. OBJECTIVES: To test the hypothesis that CMN may be derived from cutaneous stem cells. METHODS: Sixty-six CMN samples from 44 patients were stained for immunohistochemical (IHC) markers of melanocytic differentiation (TYR, TRP1, TRP2, LEF1, MITF, cKit), pluripotency (nestin, fascin, CD133, CD20, CD34), monocyte/macrophage lineage (CD68, CD163, CD14), proliferation (Ki67) and MTOR/Wnt-signalling pathway activation (pS6, ß-catenin). Semiquantitative scoring compared samples with naevus cell nesting (group 1) with those with only diffuse dermal infiltration (group 2). Transmission electron microscopy (TEM) was performed on 10 samples. RESULTS: A normal melanocyte population was seen overlying many dermal CMN. Group 1 samples were significantly more likely to express melanocytic differentiation markers than group 2, and expression decreased significantly with depth. Expression of these markers was correlated with each other, and with nestin and fascin. CD20 staining was positive in a substantial proportion and was stronger superficially. Expression of ß-catenin and pS6 was almost universal. Some samples expressed monocyte/macrophage markers. TEM revealed variable naevus cell morphology, striking macromelanosomes, double cilia and microvilli. CONCLUSIONS: Congenital melanocytic naevi development frequently coexists with normal overlying melanocyte development, leading us to hypothesize that in these cases CMN are likely to develop from a cell present in the skin independent of, or remaining after, normal melanocytic migration. IHC and TEM findings are compatible with CMN cells being of cutaneous stem-cell origin, capable of some degree of melanocytic differentiation superficially.

Biomechanical allometry in hominoid thoracic vertebrae.

Considerable differences in spinal morphology have been noted between humans and other hominoids. Although comparative analyses of the external morphology of vertebrae have been performed, much less is known regarding variations in internal morphology (density) and biomechanical performance among humans and closely related non-human primates. In the current study we utilize density calibrated computed tomography images of thoracic vertebral bodies from hominoids (n=8-15 per species, human specimens 20-40 years of age) to obtain estimates of vertebral bone strength in axial compression and anteroposterior bending and to determine how estimates of strength scale with animal body mass. Our biomechanical analysis suggests that the strength of thoracic vertebral bodies is related to body mass (M) through power law relationships (y proportional, variant M(b)) in which the exponent b is 0.89 (reduced major axis) for prediction of axial compressive strength and is equal to 1.89 (reduced major axis) for prediction of bending strength. No differences in the relationship between body mass and strength were observed among hominoids. However, thoracic vertebrae from humans were found to be disproportionately larger in terms of vertebral length (distance between cranial and caudal endplates) and overall vertebral body volume (p<0.05). Additionally, vertebral bodies from humans were significantly less dense than in other hominoids (p<0.05). We suggest that reduced density in human vertebral bodies is a result of a systemic increase in porosity of cancellous bone in humans, while increased vertebral body volume and length are a result of functional adaptation during growth resulting in a vertebral bone structure that is just as strong, relative to body mass, as in other hominoids.

Australopithecus garhi: a new species of early hominid from Ethiopia.

The lack of an adequate hominid fossil record in eastern Africa between 2 and 3 million years ago (Ma) has hampered investigations of early hominid phylogeny. Discovery of 2.5 Ma hominid cranial and dental remains from the Hata beds of Ethiopia's Middle Awash allows recognition of a new species of Australopithecus. This species is descended from Australopithecus afarensis and is a candidate ancestor for early Homo. Contemporary postcranial remains feature a derived humanlike humeral/femoral ratio and an apelike upper arm-to-lower arm ratio.

Subclinical slipped capital femoral epiphysis. Relationship to osteoarthrosis of the hip.

We examined the femora of 2665 adult human skeletons from an osteological collection to determine the prevalence of post-slip morphology termed femoral head-tilt deformity by Murray and pistol-grip deformity by Stulberg et al. The hypothesis was that primary osteoarthrosis of the hip is a secondary manifestation of a subclinical developmental disorder of the hip. The prevalence of post-slip morphology was 8 per cent (215 of 2665 skeletons). Severe osteoarthrosis was more prevalent in association with post-slip morphology (116 [38 per cent] of 306 hips) than in the matched controls (seventy-nine [26 per cent] of 306 hips) (p < 0.005). In the skeletons that had unilateral post-slip morphology, severe osteoarthrosis was more prevalent in the involved hips (thirty-one [37 per cent] of eighty-three) than in the contralateral, normal hips (eighteen [22 per cent] of eighty-three) (p < 0.05). Post-slip morphology, which was unrelated to age, was found to be a major risk factor for the development of high-grade osteoarthrosis. We noted evidence of high-grade osteoarthrosis in sixty-three (68 percent) of the ninety-three hips with minimum post-slip morphology in skeletons from individuals who had been fifty-six years old or more at the time of death compared with forty-five (48 percent) of the ninety-three control hips. This difference was significant (p < 0.025) [corrected]. The osteoarthrosis in the hips with post-slip morphology was distinctly characterized by anterior flattening of the acetabulum, cystic degeneration in the anterior metaphyseal-epiphyseal region, and progression to global osteoarthrosis of the hip.

Anterior extension of the thoracic vertebral bodies in Scheuermann's kyphosis. An anatomic study.

Changes consistent with Scheuermann's kyphosis were noted in 103 specimens (7.4%) of a sample of 1,384 thoracic spines in the Hamann-Todd collection of human skeletons. In 94% of the affected vertebrae, a distinct anterior elongation of the vertebral centrum was present. This anterior extension was composed of mature cancellous bone and was morphologically and roentgenographically different from marginal osteophyte formation. It was not present in any vertebrae of a control group of 50 unaffected spines. Associated findings included vertebral wedging and Schmorl's nodes.

Vertebral body and posterior element morphology: the normal spine in middle life.

Multiple morphologic parameters were studied in 50 normal adult vertebral columns ranging in age from 20 to 40 years at the time of death. Posterior element morphology is highly variable and largely unpredictable. Minimum pedicle diameters ranged from 1.8 mm at T6 to 6.4 mm at L5, and did not correlate with any more readily measured vertebral dimensions. Penetration of 5 mm screw threads through pedicle cortex can be expected to occur routinely in the lower thoracic spine, and in a lesser but significant number of lumbar vertebrae.

Vertebral alterations in Scheuermann's kyphosis.

In a cadaver-derived skeletal collection of 1,384 thoracolumbar spinal columns, 103 (7.4%) individuals with vertebral changes of Scheuermann's kyphosis were identified. Anterior extension of the vertebral specimens was noted in 94% of affected specimens. No evidence of osteoporosis was noted by single-photon absorptiometric analysis in the affected sample compared with a normal control group. Biopsy specimens from two immature patients obtained at surgery suggested disorganized endochondral ossification similar to that noted in Blount's disease. It was concluded that increased pressure on the anterior margin of the centrum is responsible for histologic and morphologic changes of Scheurermann's kyphosis.

Post-mortem description of slipped capital femoral epiphysis.

We found, in a museum collection of skeletons, nine adult hips with untreated slipped capital femoral epiphyses. All the specimens were from men, five black and two white. Their mean age at death was 44 years. Seven of the femora were retroverted beyond neutral and five had true varus deformities. Osteoarthritis was detected in eight of the hips and the most severe degeneration was seen in the most deformed hips. Radiography revealed that cysts which appeared to occupy the femoral head in fact lay in the metaphyseal bone of the femoral neck.

An experimental test of "the mozart effect": does listening to his music improve spatial ability?

This experiment was designed as a test of the 1993 findings of Rauscher, Shaw, and Ky who reported a positive effect of listening to classical music on spatial reasoning. Present results do not demonstrate the "Mozart effect." In our study, 114 students were pretested on items from the Raven's Progressive Matrices--Advanced Form, then instructed to listen to either 8 min. of Mozart's music, relaxation instructions, or silence. Then subjects were posttested on an equivalent set of Raven's items. The subjects were also asked to provide information about their musical background and preferences. All instructions and treatments were audiotaped and played to individual subjects through earphones in the university language laboratory, ensuring standardization of procedures. Subjects in all 3 treatment groups showed a practice effect, but this improvement in Raven's scores was not dependent on the type of treatment received. There were no differences in Raven's scores among groups before or after treatment so our results do not confirm the prior ones. There was no evidence that the brief music had a different effect on subsequent problem solving according to listeners' musical background and training.

Influenza virus specific CD8⁺ T cells exacerbate infection following high dose influenza challenge of aged mice.

Influenza viruses cause severe illnesses and death, mainly in the aged population. Protection afforded by licensed vaccines through subtype-specific neutralizing antibodies is incomplete, especially when the vaccine antigens fail to closely match those of the circulating viral strains. Efforts are underway to generate a so-called universal influenza vaccine expressing conserved viral sequences that induce broad protection to multiple strains of influenza virus through the induction of CD8⁺ T cells. Here we assess the effect of a potent antiviral CD8⁺ T cell response on influenza virus infection of young and aged mice. Our results show that CD8⁺ T cell-inducing vaccines can provide some protection to young mice, but they exacerbate influenza virus-associated disease in aged mice, causing extensive lung pathology and death.

Home visits after hospitalization: enhancing baccalaureate nursing students' gerontologic clinical experience.

This article describes posthospitalization visits by 83 nursing students to 57 older patients and their caregivers discharged from two large academic medical centers and one community hospital. Patient and caregiver interviews in the home focused on the areas of geriatric assessments of cognitive and functional status, patient and caregiver satisfaction with recent hospitalization, ongoing health management, patient teaching, and discharge planning.

Early growth rates and their relationships to mortalities of five breeds of chickens following exposure to acute gamma radiation stress.

Growth and mortality responses were recorded for 541 chicks, representing five different breeds of chickens, following acute exposures to gamma radiation stress at two days of age. Although there were no statistically significant differences in the LD50/30 of the five breeds studied, Cobb broilers showed the highest (1580R) and White Leghorn bantams the lowest (980R) levels, respectively. Other breeds studied included the standard White Leghorn, Athens Randombreds and a strain of feral bantam. Growth rates of body weights were proportionately more depressed by radiation stress than were body sizes, as measured by the lengths of the culmen, tarsus, middle toe and longest primary wing feather of all 32 day-old survivors. Among these structures, the length of the culmen seemed to be the least affected by radiation stress in all of the breeds studied. Feral bantams were able to tolerate the greatest depression in weight gain before exhibiting mortality at exposures below their LD50/30' while Cobb broilers tolerated the greatest depression of weight gain at higher exposure levels. There was a suggestion that those characteristics which were strongly selected for in the course of a particular breed's development were those which experienced the greatest proportional depressions following exposure to gamma radiation stress.

Hamann-Todd Collection aging studies: osteoporosis fracture syndrome.

The study presents a retrospective analysis of distal radius, proximal femur, vertebral, and sacral fractures that occurred in 938 Hamann-Todd Collection skeletons. Individuals included in the investigation were retrieved from dissecting room cadavers in Cleveland, Ohio, between the years 1910 and 1940. Demographic analysis showed that the mean ages at death for blacks and whites included in the study were 41.9 and 53.8 years, respectively. Evaluations of fracture repair status were made for all fractures that were identified. Observations that document side of involvement and unilateral/bilateral distribution were made for distal radius and hip fractures. It was found that the age-, sex-, and race-related fracture patterns which characterize the early 20th century Hamann-Todd sample strongly correspond in distribution and magnitude to those seen in modern American and European urban industrial communities. The distal radius, hip, vertebral, and sacral fractures which were identified in individuals over 60 years of age appear to be a primary result of skeletal fragility due to age progressive bone loss. However, it is suggested that the early onset and high frequency of distal radius fractures seen in climacteric Caucasian women may be more directly due to accidental falls initiated by a greater frequency, intensity, and duration of vasomotor disturbances which are known to accompanay estrogen withdrawal in perimenopausal white females.

The calcaneus of Australopithecus afarensis and its implications for the evolution of bipedality.

Calcanei from African apes, modern humans, and Australopithecus afarensis are compared to investigate the anatomical and mechanical changes that occurred in this bone as a result of the transition to terrestrial bipedality. Features analyzed include the cross-sectional area and volume of the calcaneal tuber, the geometry and orientation of the articular surfaces, and the surface topography of the calcaneal corpus. Calcaneal morphology is unequivocal in its partitioning of quadrupedal pongids and bipedal hominids.

Metatarsophalangeal joints of Australopithecus afarensis.

Metatarsophalangeal joints from African pongids, modern humans, and Australopithecus afarensis are compared to investigate the anatomical and mechanical changes that accompanied the transition to terrestrial bipedality. Features analyzed include the shape and orientation of the metatarsal heads, excursion of the metatarsophalangeal joints, and orientation of the basal articular surface of the proximal phalanges. These features unequivocally segregate quadrupedal pongids and bipedal hominids and demonstrate a clear adaptation to terrestrial bipedality in the Hadar pedal skeleton.

Hallucal tarsometatarsal joint in Australopithecus afarensis.

Hallucal tarsometatarsal joints from African pongids, modern humans, and Australopithecus afarensis are compared to investigate the anatomical and mechanical changes that accompanied the transition to terrestrial bipedality. Features analyzed include the articular orientation of the medial cuneiform, curvature of the distal articular surface of the medial cuneiform, and the articular configuration of the hallucal metatarsal proximal joint surface. Morphological characteristics of the hallucal tarsometatarsal joint unequivocally segregate quadrupedal pongids and bipedal hominids.

Talocrural joint in African hominoids: implications for Australopithecus afarensis.

Talocrural joints of the African apes, modern humans, and A.L.288-1 are compared in order to investigate ankle function in the Hadar hominids. Comparisons between the hominids and African pongids clearly illustrate the anatomical and mechanical changes that occurred in this joint as a consequence of the evolutionary transition to habitual bipedality. Features which are considered include the obliquity of the distal tibial articular surface, the shape of the talar trochlea, and the location and functional implications of the talocrural axis. In every functionally significant feature examined the A.L.288-1 talocrural joint is fully bipedal. Moreover, the Hadar ankle complex also shows the functional constraints which are necessarily imposed by the adaptation to habitual bipedalism.