1,963 research outputs found
A study of physiological mechanisms and inter-relations between systemic and regional blood volume, blood flow and electrolyte balance Interim progress report, Jun. 30 - Dec. 31, 1967
Regulation of sodium excretion in dog, and effects of atrial size and function upon secretion of sodium load - circulatory response to upright til
An analysis of the influences of intelligence and age differences upon fifth-grade children's preferences for school subjects
Thesis (M.A.)--Boston University, 1948. This item was digitized by the Internet Archive
The construction and evaluation of a social studies vocabulary association test for intermediate grades.
Thesis (Ed.D.)--Boston University
Herd health status and management practices on 16 Irish suckler beef farms
peer-reviewedBackground: There have been few studies published internationally which document herd health management practices in suckler beef herds and no published Irish studies. The study objective was to document herd health status and management practices on sixteen Irish suckler beef herds over a two year period (2009–2010). The farms used in the study were part of the Teagasc BETTER farm beef programme. The mean (s.d.) herd size, stocking rate and farm size was 68 cows (27.6), 2.0 LU/ha (0.3) and 64.3 (21.6) adjusted hectares, respectively. Two questionnaires were designed; 1) a farmer questionnaire to collect information on farm background and current herd health control practices and 2) a veterinary questionnaire to collect information on the extent of animal health advice given by veterinarians to their clients and identification of any on-farm herd health issues.
Results: Dystocia, calf pneumonia, and calf diarrhoea, in that order, were identified as the primary herd health issues in these Irish suckler beef herds. In addition, substantial deficiencies in biosecurity practices were also identified on these farms.
Conclusions: The findings of this study may serve as the focus for future research in animal health management practices in Irish suckler beef herds
Nematode control in suckler beef cattle over their first two grazing seasons using a targeted selective treatment approach
peer-reviewedBackground
With concerns over the development of anthelmintic resistance in cattle nematode populations, we must re-examine our approach to nematode control in cattle. Targeted selective treatments (TST), whereby individual animals are treated instead of entire groups, are being investigated as an alternative. The study objective was to determine if anthelmintic usage could be reduced using a TST-based approach to nematode control in spring-born suckler beef cattle over their first and second grazing seasons (SGS) without affecting performance. In the first grazing season (FGS), 99 calves with an initial mean (s.d.) calf age and live weight on day 0 (June 28th 2012) of 107 (23.1) days and 160 (32.5) kg, respectively, were used. The study commenced on day 0 when calves were randomised and allocated to one of two treatments; 1), standard treatment (control) and 2), TST. Control calves were treated subcutaneously with ivermectin on days 0, 41 and 82 in the FGS. All calves were treated with ivermectin on day 124 and housed on day 133. In the SGS, only heifer calves from the FGS were used and control heifers were treated with ivermectin on day 393. Animals were weighed, blood and faecal sampled every three weeks. The TST animals were treated with ivermectin if thresholds based on a combination of plasma pepsinogen concentrations, faecal egg count and/or the presence of Dictyocaulus viviparus larvae in faeces (FGS only) were reached.
Results
No TST calves reached the treatment threshold criteria in the FGS. The FGS average daily live weight gain (ADG ± s.e.m.) for control and TST group calves was 0.89 ± 0.02 kg and 0.94 ± 0.02 kg day−1, respectively (P = 0.17). In the SGS, all heifers were treated with ivermectin on day 431 due to clinical signs of respiratory disease. The ADG for control and TST heifers from turnout on day 321 to day 431 was 0.90 ± 0.04 and 0.80 ± 0.04 kg day−1, respectively (P = 0.03).
Conclusions
Spring-born FGS suckler beef calves require minimal anthelmintic treatment to maintain performance. In contrast, clinical parasitic disease may develop in the SGS unless appropriate anthelmintic treatment is provided
Effects of Asenapine on Agitation and Hostility in Adults with Acute Manic or Mixed Episodes Associated with Bipolar I Disorder
BACKGROUND:
Bipolar disorder is associated with an increased risk of aggression. However, effective management of hostility and/or agitation symptoms may prevent patients from becoming violent. This analysis investigated the efficacy of the antipsychotic asenapine on hostility and agitation in patients with bipolar I disorder. METHODS:
Data were pooled from three randomized, double-blind, placebo-controlled, Phase III trials of asenapine in adults with manic or mixed episodes of bipolar I disorder (NCT00159744, NCT00159796, and NCT00764478). Post hoc analyses assessed the changes from baseline to day 21 on the Young Mania Rating Scale (YMRS) and the Positive and Negative Syndrome Scale (PANSS) hostility-related item scores in asenapine- or placebo-treated patients with at least minimal or mild symptom severity and on the PANSS-excited component (PANSS-EC) total score in agitated patients. Changes were adjusted for improvements in overall mania symptoms to investigate direct effects on hostility. RESULTS:
Significantly greater changes in favor of asenapine versus placebo were observed in YMRS hostility-related item scores (irritability: least squares mean difference [95% confidence interval] =-0.5 [-0.87, -0.22], P=0.001; disruptive-aggressive behavior: -0.7 [-0.99, -0.37], PP=0.0181), and PANSS-EC total score (-1.4 [-2.4, -0.4]; P=0.0055). Changes in the YMRS disruptive-aggressive behavior score and the sum of the hostility-related items remained significant after adjusting for improvements in other YMRS item scores. CONCLUSION:
Asenapine significantly reduced hostility and agitation in patients with bipolar I disorder; improvement was at least partially independent of overall improvement on mania symptoms
Microevolutionary distribution of isogenicity in a self-fertilizing fish (Kryptolebias marmoratus) in the Florida Keys.
The mangrove rivulus Kryptolebias marmoratus and a closely related species are the world's only vertebrates that routinely self-fertilize. Such uniqueness presents a model for understanding why this reproductive mode, common in plants and invertebrates, is so rare in vertebrates. A survey of 32 highly polymorphic loci in >200 specimens of mangrove rivulus from multiple locales in the Florida Keys, USA, revealed extensive population-genetic structure on microspatial and micro-temporal scales. Observed heterozygosities were severely constrained, as expected for a hermaphroditic species with a mixed-mating system and low rates of outcrossing. Despite the pronounced population structure and the implied restrictions on effective gene flow, isogenicity (genetic identity across individuals) within and among local inbred populations was surprisingly low even after factoring out probable de novo mutations. Results indicate that neither frequent bottlenecks nor directional genetic adaptation to local environmental conditions were the primary driving forces impacting multilocus population-genetic architecture in this self-fertilizing vertebrate species. On the other hand, a high diversity of isogenic lineages within relatively small and isolated local populations is consistent with the action of diversifying selection driven by the extreme spatio-temporal environmental variability that is characteristic of mangrove habitats
Developmental plasticity of the stress response in female but not in male guppies
To survive, animals must respond appropriately to stress. Stress responses are costly, so early-life experiences with potential stressors could adaptively tailor adult stress responses to local conditions. However, how multiple stressors influence the development of the stress response remains unclear, as is the role of sex. Trinidadian guppies (Poecilia reticulata) are small fish with extensive life-history differences between the sexes and population variation in predation pressure and social density. We investigated how sex and early-life experience influence hormonal stress responses by manipulating conspecific density and perceived predation risk during development. In adults, we sampled cortisol twice to measure initial release and change over time in response to a recurring stressor. The sexes differed considerably in their physiological stress response. Males released more cortisol for their body mass than females and did not reduce cortisol release over time. By contrast, all females, except those reared at high density together with predation cues, reduced cortisol release over time. Cortisol responses of males were thus less dynamic in response to current circumstances and early-life experiences than females, consistent with life-history differences between the sexes. Our study underscores the importance of early-life experiences, interacting ecological factors and sex differences in the organization of the stress response
Dung Beetles Eat Acorns to Increase Their Ovarian Development and Thermal Tolerance
Animals eat different foods in proportions that yield a more favorable balance of nutrients. Despite known examples of these behaviors across different taxa, their ecological and physiological benefits remain unclear. We identified a surprising dietary shift that confers ecophysiological advantages in a dung beetle species. Thorectes lusitanicus, a Mediterranean ecosystem species adapted to eat semi-dry and dry dung (dung-fiber consumers) is also actively attracted to oak acorns, consuming and burying them. Acorn consumption appears to confer potential advantages over beetles that do not eat acorns: acorn-fed beetles showed important improvements in the fat body mass, hemolymph composition, and ovary development. During the reproductive period (October-December) beetles incorporating acorns into their diets should have greatly improved resistance to low-temperature conditions and improved ovarian development. In addition to enhancing the understanding of the relevance of dietary plasticity to the evolutionary biology of dung beetles, these results open the way to a more general understanding of the ecophysiological implications of differential dietary selection on the ecology and biogeography of these insects
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