Udder health in organic dairy cattle in Northern Spain

This paper presents first data on the udder health status of organic dairy farms in Northern Spain and analyses some management and productive characteristics related to milk production comparing with the conventional sector. Five certified organic farms from the Cantabrian Region were monitored monthly from February 2006 to January 2008 and individual samples of all lactating cows were taken from parturition to the end of lactation. Although organic farms in our study showed a great individual variability, overall these were small (<50 lactating cows) traditional farms, with a high degree of pasture (66-82% dry matter intake) and a milk production (average milk yield: 5950 L) 23% lower compared with the reference conventional sector (<50 cow farms). The organic farms had higher (p<0.05) average number of calves per cow (3.93) and a lower number of first-lactation cows (16.9%) than the comparable conventional farms (2.47 calves per cow and 33.1% first-lactation cows). Organic farms showed higher (p<0.05) somatic cell counts (SCC) than the reference conventional farms (mean log10±SD for all cows: 5.25±0.49 and 5.06±0.59, respectively). Detailed analysis of the SCC depending on the number of lactation and % of monthly SCC tests with linear scores indicative of udder infection suggest that while the heifers’ sanitary condition at the beginning of their productive cycle was similar in both types of farms, this seems to become worse along the productive cycle in the organics. This could be related to a low use of antibiotics for prophylaxis and treatment of udder infections and merits further investigationINIA (ref. RTA2006-00132-C02-01)S

Assessment of Postural Load during Melon Cultivation in Mediterranean Greenhouses

Health and safety at work directly influence the development of sustainable agriculture. In the agricultural sector, many farm workers suffer musculoskeletal disorders caused by forced posture. The objective of this research is to assess working postures during melon cultivation in Almería-type greenhouses. The Ovako Working Posture Assessment System (OWAS) has been used with pictures of the tasks. The variables studied by multiple correspondence analysis were as follows: Subtask, Posture code, Back, Arms, Legs, Load, Risk, and Risk combination. The OWAS analysis showed that 47.57% of the postures were assessed as risk category 2, 14.32% as risk category 3, 0.47% as risk category 4, and the rest as risk category 1. Corrective measures should be implemented immediately, as soon as possible, or in the near future, depending on the risks detected

The use of seaweed from the Galician coast as a mineral supplement in organic dairy cattle

This study was designed to assess the value of seaweeds from the Galician coast as a source of minerals (especially iodine (I) but also other micro-minerals) in organic dairy cattle. It was conducted in an organic dairy farm in the Lugo province that typically represents the organic milk production in NW Spain. The animal’s diet consisted mainly of local forage (at pasture or as hay and silage in the winter) and 5 kg of purchased concentrate/day per animal (representing 23.5% of feed intake). Based on the mineral composition of the diet, the physiological requirements and the EU maximum authorised levels in feed, a supplement composed by Sea Lettuce (Ulva rigida) (as flakes, 80%), Japanese Wireweed (Sargasum muticum) (flakes, 17.5%) and Furbelows (Saccorhiza polyschides) (powder, 2.5%) was formulated to give 100 g/animal per day. Sixteen Holstein Friesian lactating cows were randomly selected and assigned to the control (n=8) and algae-supplemented groups (n=8). Both groups had exactly the same feeding and management with the exception of the algae supplement, which was mixed with the concentrate feed and given to the animals at their morning milking for 10 weeks. Heparinised blood (for plasma analysis) and milk samples were collected at 2-week intervals and analysed for toxic and trace element concentrations by inductively coupled plasma-mass spectrometry or inductively coupled plasma-optical emission spectrometry. The algae supplement significantly improved the animals’ mineral status, particularly I and selenium that were low on the farm. However, the effect of the algae supplement on the molybdenum status in cattle needs further investigation because of its great relevance on copper metabolism in ruminants. The I supply deserves special attention, since this element is at a very high concentration in brown-algae species and it is excreted in the milk proportionally to its concentration in plasma concentrations (mean±s.e. in the algae-supplemented and control groups were 268±54 and 180±42 µg/l, respectively)This work was supported by the Spanish Government (projectcode AGL2010-21026) and Centro Tecnológico Agroalimentario de Lugo (CETAL)S

On the decomposition of the De Rham complex on formal schemes

We show that if X is a pseudo-proper smooth noetherian formal scheme over a positive characteristic p field k then its De Rham complex τ ≤p (FX/k ∗Ωb• X/k) is decomposable. Along the way we establish the Cartier isomorphism Ωbi X(p)/Y γ→ Hi (FX/Y ∗Ωb•X/Y) associated to a map f : X → Y of positive characteristic p noetherian formal schemes where X(p) denotes the base change of X along the Frobenius morphism of Y and FX/Y denotes the relative Frobenius of X over Y.Ministerio de Economía y Competitividad | Ref. MTM2014-59456Agencia Estatal de Investigación | Ref. MTM2017-89830-PXunta de Galicia | Ref. ED431C 2019/1

Low Levels of Amyloid Precursor Protein (APP) Promote Neurogenesis and Decrease Gliogenesis in Human Neural Stem Cells

Amyloid precursor protein (APP) has been widely studied due to its association with Alzheimer's disease (AD). However, the physiological functions of APP are still largely unexplored. APP is a transmembrane glycoprotein whose expression in humans is abundant in the central nervous system. Specifically, several studies have revealed the high expression of APP during brain development. Previous studies in our laboratory revealed that a transient increase in APP expression induces early cell cycle exit of human neural stem cells (hNSCs) and directs their differentiation towards glial cells (gliogenesis) while decreasing their differentiation towards neurons (neurogenesis). In the present study, we have evaluated the intrinsic cellular effects of APP down-expression (using siRNA) on cell death, cell proliferation, and cell fate specification of hNSCs. Our data indicate that APP silencing causes cellular effects opposite to those obtained in previous APP overexpression assays, inducing cell proliferation in hNS1 cells (a model line of hNSCs) and favoring neurogenesis instead of gliogenesis in these cells. In addition, we have analyzed the gene and protein expression levels of β-Catenin as a possible molecule involved in these cellular effects. These data could help to understand the biological role of APP, which is necessary to deepen the knowledge of AD.This research was supported by a grant from the Spanish Ministry of Science and Innovation (RTI2018-101663-B-100) and grant number PID2021-126715OB-I00 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”. R.C. was supported by an FPU predoctoral contract from Universidad de Alcalá (FPU-UAH).S

Dairy cow nutrition in organic farming systems. Comparison with the conventional system

The energy supplied by the high-forage diets used in organic farming may be insufficient to meet the requirements of dairy cattle. However, few studies have considered this problem. The present study aimed to analyze the composition of the diets and the nutritional status (focusing on the energy–protein balance of the diets) of dairy cattle reared on organic farms in northern Spain, which are similar to other organic farming systems in temperate regions. Exhaustive information about diets was obtained from organic (ORG) and representative conventional grazing (GRZ) and conventional no-grazing (CNG) farms. Samples of feed from the respective farms were analyzed to determine the composition. Overall, the diets used on the ORG farms were very different from those used on the CNG farms, although the difference was not as evident for GRZ. The CNG farms were characterized by a higher total dry matter intake with a high proportion of concentrate feed, maize silage and forage silage. By contrast, on ORG and GRZ farms, the forage, pasture and fibre intake were the most important variables. The ration used on ORG farms contained a significantly higher percentage of ADF and lower organic matter (OM) content than the rations used in both of the conventional farming systems, indicating that the diets in the former were less digestible. Although the protein concentration in the diets used on the grazing farms (ORG and GRZ) was higher than those used on CNG farms, the protein intake was similar. The results indicated an imbalance between energy and protein due to the low level of energy provided by the ORG diets, suggesting that more microbial protein could be synthesized from the available rumen-degraded dietary nitrogen if rumen-fermentable OM was not limiting. The imbalance between energy and protein led to a reduced amount of total digestible protein reaching the intestine and a lower milk yield per kilogram of CP intake on the ORG farms. In order to improve the protein use efficiency and consequently to reduce the loss of nitrogen to the environment, organic farming should aim to increase the energy content of cattle diets by improving forage quality and formulating rations with more balanced combinations of forage and grainThis study was supported by the Spanish Government (project code AGL2010-21026) and Centro Tecnológico Agroalimentario de Lugo (CETAL). I. Orjales is in receipt of a FPU fellowship (Ref. FPU14/01473) from the Spanish Ministry of Education, Culture and SportsS

Histochemistry evaluation of the oxidative stress and the antioxidant status in Cu-supplemented cattle

The aim of this paper is to evaluate at a histopathological level the effect of the most commonly used copper (Cu) supplementation (15 mg/kg dry matter (DM)) in the liver of intensively reared beef cattle. This was done by a histochemistry evaluation of (i) the antioxidant capacity in the liver – by the determination of metallothioneins (MT) and superoxide dismutase (SOD) expression – as well as (ii) the possible induction of oxidative damage – by the determination of inducible nitric oxide synthase (iNOS), nitrotyrosine (NITT), malondialdehyde (MDA) and 8-oxoguanine (8-oxo) – that (iii) could increase apoptotic cell death – determined by cytochrome-c (cyto-c), caspase 1 (casp1) and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL). Liver samples from Cu-supplemented (15 mg Cu sulphate/kg DM, n = 5) and non-supplemented calves (n = 5) that form part of other experiments to evaluate Cu status were collected at slaughter and processed for immunohistochemistry and TUNEL. MT expression was diffuse and SOD showed slight changes although without statistical significance. iNOS and NITT positive (+) cells significantly increased, mainly around the central veins in the animals from the Cu-supplemented group, whereas no differences were appreciated for the rest of the oxidative stress and apoptosis markers. Under the conditions of this study, which are the conditions of the cattle raised in intensive systems in NW Spain and also many European countries, routinely Cu supplementation increased the risk of the animals to undergo subclinical Cu toxicity, with no significant changes in the Cu storage capacity and the antioxidant defensive system evaluated by MT and SOD expression, but with a significant and important increase of oxidative damage measured by iNOS and NITT. The results of this study indicated that iNOS and NITT could be used as early markers of initial pathological changes in the liver caused by Cu supplementation in cattle, although more studies in cattle under different levels of Cu supplementation are neededThis work was supported by the Xunta de Galicia (Spain) through contract 07MRU030261PR and by a research grant María Barbeito awarded to M. García-Vaquero by the Dirección Xeral de Investigación, Desenvolvemento e Innovación from Xunta de Galicia and to FSE (Fondo Social Europeo) funds through Programa de Recursos Humanos, do Plan Galego de Investigación, Desenvolvemento e Innovación Tecnolóxica de GaliciaS

Seasonal Variation of the Proximate Composition, Mineral Content, Fatty Acid Profiles and Other Phytochemical Constituents of Selected Brown Macroalgae

The main objective was to determine the chemical, phytochemical, fatty acid and mineral profiles of three commercially relevant brown macroalgae (Laminaria digitata, Laminaria hyperborea and Ascophyllum nodosum) collected each season for two years off the west coast of Ireland. All the chemical, phytochemical, fatty acid and minerals analysed varied significantly depending on the macroalgal species, season and year of collection. Overall, the protein contents of macroalgae were negatively correlated with carbohydrate content. Protein (2–11%) was at its highest during winter and/or spring, decreasing to a minimum during summer and/or autumn. The three macroalgal species analysed in this study had clearly differentiated fatty acid profiles. The concentration of fatty acids was higher in A. nodosum compared with both Laminaria species. The mineral profile of the three macroalgal species was rich in essential metals, particularly Ca, Mg and P, while the levels of I were approximately 9- to 10-fold higher in both Laminaria spp. compared with A. nodosum. The levels of toxic metals (Cd, Hg and Pb) in all the macroalgal species studied were low in the current study; while the levels of total As were high (49–64 mg/kg DW macroalgae) compared with previous reportsThis work was supported by Science Foundation Ireland (SFI) (grant number: 14/IA/2548)S

The derived category of quasi-coherent sheaves and axiomatic stable homotopy

We prove in this paper that for a quasi-compact and semi-separated (non necessarily noetherian) scheme X, the derived category of quasi-coherent sheaves over X, D(A_qc(X)), is a stable homotopy category in the sense of Hovey, Palmieri and Strickland, answering a question posed by Strickland. Moreover we show that it is unital and algebraic. We also prove that for a noetherian semi-separated formal scheme X, its derived category of sheaves of modules with quasi-coherent torsion homologies D_qct(X) is a stable homotopy category. It is algebraic but if the formal scheme is not a usual scheme, it is not unital, therefore its abstract nature differs essentially from that of the derived category of a usual scheme.Comment: v2: 31 pages, some improvements in exposition; v3 updated bibliography, to appear Adv. Mat