Effects of acute lying and sleep deprivation on metabolic and inflammatory responses of lactating dairy cows

Dairy cows that are restricted from lying down have a reduced ability to sleep. In other species, sleep loss is a key risk factor for disease, mediated by changes in metabolic and inflammatory responses. The cumulative effect of lying and sleep deprivation on cow health is unknown. The objective was to determine the effects of lying and sleep deprivation on metabolic and inflammatory responses of dairy cows. Data were collected from 8 multiparous and 4 primiparous lactating cows (199 +/- 44 d in milk, 77 +/- 30 d pregnant; mean +/- standard deviation) enrolled in a study using a crossover design. Each cow was exposed to 2 treatments meant to induce sleep loss: (1) human disturbance (imposed by researchers making noise or physical contact when the cow's posture suggested sleep) and (2) lying deprivation (imposed by a wooden grid placed on the pen floor). Cows experienced a 24-h baseline period (d - 1) followed by a 24-h treatment period (d 0), with a 12-d washout period between treatments. Baseline and treatment periods were imposed from 2100 to 2059 h. Cows were housed in individual pens during the acclimation period (d - 3 and - 2), d - 1, and d 0. Nonesterified fatty acid and glucose concentrations were measured at 0300, 0900, 1500, and 2059 h on d - 1 and 0. Proinflammatory cytokine mRNA [tumor necrosis factor (TNF), interleukin-1B (IL1B), and interleukin-6 (IL6)] abundance in whole-blood leukocytes, both nonstimulated and stimulated with lipopolysaccharide, were assessed at 2059 h on d -1 (end of baseline) and d 0 (end of treatment). Nonesterified fatty acids and glucose varied by time of day but were not affected by treatment or day. The abundances of TNF and IL1B from both stimulated and nonstimulated cells were higher following 24 h of lying deprivation (d 0) compared with baseline (d -1). Abundance of IL6 was increased in nonstimulated cells after lying deprivation compared with baseline. In contrast, human disturbance for 24 h did not alter TNF, IL1B, or IL6 abundance relative to baseline levels. These results suggest that a short period of lying deprivation generally increases inflammatory responses but not metabolic responses.Peer reviewe

Forage Systems to Optimize Agronomic and Economic Performance in Organic Dairy Systems

Organic dairy production in the USA is growing, but most forage systems research focuses on conventional production practices. As a result, organic dairy producers have limited science-based information to assist with farm and livestock management. The objective of this project was to use a multi-faceted approach to determine the ideal species mixtures for organic dairy production as well as document forage quality, forage yield, soil characteristics, milk production and milk quality during the grazing season. The forages studied ranged from a single species monoculture to a four species mixture of warm and cool season grasses and legumes. Nine distinct forage systems were seeded into small plots at the University of Tennessee and University of Kentucky research farms using organic practices. These plots were monitored for three years for yield, quality, species composition, and soil characteristics. The four best performing forage systems were planted in small paddocks on organic dairy farms in Tennessee and Kentucky to evaluate forage yield, forage quality, seasonality of production, and suitability for on-farm milk production. The superior forage system was established on a 4 ha paddock and compared the existing forage system used by each of the dairy farms. These larger paddocks allowed continued measurements of forage yield and quality, as well as measurements of milk production, milk quality, and grazing behaviour of the animals. The information from this project is currently being incorporated into a total farm management system for organic dairy producers in the Southeastern USA

Steroid receptor coactivator 1 deficiency increases MMTV-neu mediated tumor latency and differentiation specific gene expression, decreases metastasis, and inhibits response to PPAR ligands

<p>Abstract</p> <p>Background</p> <p>The peroxisome proliferator activated receptor (PPAR) subgroup of the nuclear hormone receptor superfamily is activated by a variety of natural and synthetic ligands. PPARs can heterodimerize with retinoid X receptors, which have homology to other members of the nuclear receptor superfamily. Ligand binding to PPAR/RXRs results in recruitment of transcriptional coactivator proteins such as steroid receptor coactivator 1 (SRC-1) and CREB binding protein (CBP). Both SRC-1 and CBP are histone acetyltransferases, which by modifying nucleosomal histones, produce more open chromatin structure and increase transcriptional activity. Nuclear hormone receptors can recruit limiting amounts of coactivators from other transcription factor binding sites such as AP-1, thereby inhibiting the activity of AP-1 target genes. PPAR and RXR ligands have been used in experimental breast cancer therapy. The role of coactivator expression in mammary tumorigenesis and response to drug therapy has been the subject of recent studies.</p> <p>Methods</p> <p>We examined the effects of loss of SRC-1 on MMTV-neu mediated mammary tumorigenesis.</p> <p>Results</p> <p>SRC-1 null mutation in mammary tumor prone mice increased the tumor latency period, reduced tumor proliferation index and metastasis, inhibited response to PPAR and RXR ligands, and induced genes involved in mammary gland differentiation. We also examined human breast cancer cell lines overexpressing SRC-1 or CBP. Coactivator overexpression increased cellular proliferation with resistance to PPAR and RXR ligands and remodeled chromatin of the proximal epidermal growth factor receptor promoter.</p> <p>Conclusions</p> <p>These results indicate that histone acetyltransferases play key roles in mammary tumorigenesis and response to anti-proliferative therapies.</p

Impaired Neutrophil Migration Associated with Specific Bovine CXCR2 Genotypes

Bovine mastitis continues to be the most detrimental factor for profitable dairying. Recent research conducted within our laboratory has identified a genetic marker in the CXCR2 gene associated with mastitis susceptibility. The objective of the present study was to evaluate the migratory ability of neutrophils from cows with different CXCR2 +777 genotypes. Neutrophils isolated from peripheral blood of 30 Holstein cows were tested for in vitro migration and adhesion molecule expression. Cows with the CC or GC genotype at CXCR2 +777 showed significantly lower neutrophil migration to recombinant human interleukin-8 (rhIL-8) than cows with the GG genotype (P < 0.05). Cows with the CC genotype at CXCR2 +777 also showed decreased neutrophil migration to zymosan-activated serum compared to these same cows (P < 0.05). Decreased upregulation of CD18 expression was observed after stimulation with rhIL-8 in cows expressing the CXCR2 +777 CC genotype compared to cows expressing the GG genotype (P < 0.05). A similar trend was observed for CD11b (P < 0.10). However, no difference in CD62 downregulation was observed with respect to genotype. These results provide initial evidence for a phenotypic association between a single nucleotide polymorphism and neutrophil function in dairy cows, as well as potential insight into specific mechanisms affected in cows more susceptible to mastitis

Surface appearance and mechanical strength of multi-layer polymeric films

This paper deals with the analysis of a multi-layer polymeric film made from a hybrid organic-inorganic bond-layer, a decorative epoxy-based basecoat and, finally, a protective polyurethane-based topcoat. The establishment of visual appearance and mechanical strength of the multi-layer polymeric films has been investigated by varying both baking time and temperature on a very wide range. Furthermore, two different two-step baking procedures (i.e., with and without full post-curing of the topcoat) were also proposed and comparatively evaluated. Improved trends of average roughness and mechanical strength of the multi-layer films were found at any time progressively higher baking time and/or temperature was set. Accordingly, the overall adhesion between multi-layer films and underlying metal surfaces was found to increase, as well. Nonetheless, experimental results show that even though satisfactory surface roughness and mechanical properties of the multi-layer films can be established over wide enough ranges of baking time and temperature with both baking procedures, an acceptable visual appearance is only achievable if the topcoat is superimposed at least on an almost fully cured basecoat. (C) 2007 Elsevier B.V. All rights reserved

Surface appearance and mechanical strength of multi-layer polymeric films

This paper deals with the analysis of a multi-layer polymeric film made from a hybrid organic–inorganic bond-layer, a decorative epoxy-basedbasecoat and, finally, a protective polyurethane-based topcoat.The establishment of visual appearance and mechanical strength of the multi-layer polymeric films has been investigated by varying both bakingtime and temperature on a very wide range. Furthermore, two different two-step baking procedures (i.e., with and without full post-curing of thetopcoat) were also proposed and comparatively evaluated.Improved trends of average roughness and mechanical strength of the multi-layer films were found at any time progressively higher baking timeand/or temperature was set. Accordingly, the overall adhesion between multi-layer films and underlying metal surfaces was found to increase, aswell. Nonetheless, experimental results show that even though satisfactory surface roughness and mechanical properties of the multi-layer filmscan be established over wide enough ranges of baking time and temperature with both baking procedures, an acceptable visual appearance is onlyachievable if the topcoat is superimposed at least on an almost fully cured basecoat

Epoxy-based thermosetting powder coatings: Surface appearance, scratch adhesion and wear resistance

The deposition of protective coatings from thermosetting polymer powders is undergoing rapid growth as an ecological, economic and energy-efficient technology. Nevertheless, a combination of conflicting needs is characterizing new formulations: (i) minimization of premature cross-linking during material production and storage; (ii) film levelling and cross-linking at the lowest possible temperature in the least possible time. We address the problem by developing an experimental study in which the evolution of film morphology and its thermal, rheological, mechanical and tribological properties are analyzed in the light of film baking time and temperature. Experimental results show that smooth films can be achieved at relatively low baking time and temperature, while film mechanical performances are not yet fully developed. In contrast, good film strength, adhesion and wear endurance can be attained, only if longer baking time or higher temperature is set. However, a generalized scratch map, which correlates the adhesion strength of the polymeric films with the thermo-rheological behaviour of the base material, has been also built. Our results open up the possibility of predicting best baking programs and how full film performances are progressively established with time and temperature by better understanding of the mechanisms involved in polymeric films formation from loose powders. © 2007 Elsevier B.V. All rights reserved

Microstructural and tribological characterisation of as sprayed and heat treated HVOF deposited Ni alloys

The microstructural, micromechanical (Vickers microindentation, scratch testing) and tribological (pin on disk tests against steel and alumina spherical pins) properties of three High velocity oxyfuel (HVOF) sprayed Ni based alloy coatings, namely Diamalloy 4006 (Ni-20Cr-10W-9Mo-4Cu-1B-1C-1Fe), Tribaloy-700 (Ni-32Mo-16Cr-4Si-2Co) and lnconel-625 (Ni-22Cr-9Mo-4Nb), were characterised, both in the as sprayed condition and after thermal treatments at 600°C and 800°C. As deposited Tribaloy-700 possesses a low degree of crystallinity and lower hardness; crystalline intermetallics are formed after heat treatments, definitely improving mechanical strength and tribological resistance against 100Cr6 steel counterpart, but not against alumina counterpart. The lnconel-625 and Diamalloy 4006 as sprayed coatings consist of supersaturated crystalline solid solutions. The former is not much affected by heat treatments and has low hardness and poor tribological properties. The latter, instead, displays precipitation of secondary phases after heat treatment. Particularly, the 600°C treatment improves coating strength and wear resistance against steel, whereas the 800°C one is less effective, probably because it causes excessive crystal grain size increase. © 2007 Institute of Materials, Minerals and Mining

Development and validation of a neural network for the automated detection of horn flies on cattle

When the number of horn flies that blood feed on cattle exceeds the economic threshold, they can adversely affect the health and wellbeing of their hosts. Excessive horn fly burdens also lead to reduced weight gain and, consequently, diminished profits for livestock producers. Effective management and treatment require reliable surveillance methods for estimating the degree of horn fly burden (i.e., counting the number of flies on cattle). Traditionally, these estimates are obtained through human visual estimation, either in-person or by counting images on a photo; however, these methods are costly both in terms of time and labor and are prone to subjectivity and bias. In contrast, automated methods can expedite the counting process and remove subjectivity and bias. To this end, a 2-stage method is presented here that uses computer vision and deep learning to identify the location of flies in digital images. The first stage segments the salient cow from all other parts of the image to remove flies on neighboring cattle from consideration. The second stage processes full-resolution patches of the original image and produces a heat map at the location of flies in the images. The method was trained on a set of 375 human-annotated images and tested on 120 images, where significant variation was observed amongst the human scorers. Counting results are compared to four separate human scorers and demonstrate that the neural network produces consistent results and that the method is reliable. Thus, the developed method can be used for monitoring changes in horn fly populations over time by anyone and allows for increased rigor and repeatability. An examination of individual images where the method was closest to and farthest from the human counts provides valuable insights regarding photographic processes that lead to success and failure