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1.
J Dairy Sci ; 106(11): 8033-8046, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37641257

RESUMEN

In the present experiment, 10 horned and 10 disbudded mid-lactating Brown Swiss cows were included in a crossover feeding trial with a hay or hay and concentrate diet. The effects of dietary neutral detergent fiber (NDF) content and horn status on thermoregulatory responses under thermoneutral and short-term heat stress conditions were studied, as both are considered to ease the cow's thermoregulation under an environmental heat load. Cows received either ad libitum hay and alfalfa pellets (85:15, C-, NDF content: 41.0%) or restricted amounts of hay and concentrate (70:30, C+, NDF content: 34.5%). The level of restriction applied with the C+ diet was determined from pre-experimental ad libitum intakes, ensuring that both diets provided the same intake of net energy for lactation (NEL). For data collection, cows were housed in respiration chambers for 5 d. The climatic conditions were 10°C and 60% relative humidity (RH), considered thermoneutral (TN) conditions (temperature-humidity index (THI): 52) for d 1 and 2, and 25°C and 70% RH, considered heat stress (HS) conditions (THI: 74), for d 4 and 5. On d 3, the temperature and RH were increased gradually. Compared with TN, HS conditions increased the water intake, skin temperature, respiration and heart rates, and endogenous heat production. They did not affect body temperature, feed intake, or milk production. Lowering dietary fiber content via concentrate supplementation lowered methane and increased carbon dioxide production. It did not mitigate physiological responses to HS. Although the responses of horned and disbudded cows were generally similar, the slower respiration rates of horned cows under HS conditions indicate a possible, albeit minor, role of the horn in thermoregulation. In conclusion, future investigations on nutritional strategies must be conducted to mitigate mild heat stress.

2.
Schweiz Arch Tierheilkd ; 164(9): 635-644, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36047819

RESUMEN

INTRODUCTION: The grinding intensity of pig feed is considered one potential predisposing factor for gastric ulcers, and a variety of particle size recommendations have been published for pig feeds. We subjected 51 different commercial compound feeds for pigs (38 meals, 13 pellets/granulates) to dry and/or wet sieve analysis. The amount of particles passing the finest sieve (or being soluble) was estimated by the difference to the total dry matter weighed prior to sieving. Mean particle size was calculated based on the weighted average of the material retained on the sieves (MPSsieves), and additionally with accounting for this lost material (MPStotal). Dry sieve analysis of the meals yielded MPSsieves of 0,58-2,90 mm and MPStotal of 0,58-2,89 mm; only 0,02 to 2,71 % of the dry matter passed all sieves. Wet sieve analysis of all meals and pellets yielded similar MPSsieves of 0,63-1,66 mm, but dramatically lower MPStotal of 0,26-1,04 mm; between 35 and 66 % of the dry matter was not retained on the sieves. Pellets had smaller MPS, and a higher proportion of particles passing all sieves than meals. Depending on the reference used, a maximum of 26 % of meals conformed to recommendations for pig feed particle size. None of the pelleted feeds met these criteria, irrespective of the source consulted for the recommendation. Wet sieving should be considered the standard analysis, because in dry sieving, very fine particles adhering to larger particles may not be registered separately but contribute erroneously to larger particle weight. In addition, the MPS calculation should account for material lost through the finest sieve. Reasons why Swiss pig feed does not meet particle size recommendations should be further investigated.


INTRODUCTION: L'intensité de broyage des aliments pour porcs est considérée comme un facteur potentiel de prédisposition aux ulcères gastriques et diverses recommandations sur la taille des particules ont été publiées pour les aliments pour porcs. Nous avons soumis 51 différents aliments composés commerciaux pour porcs (38 farines, 13 pellets/granulés) à une analyse par tamisage à sec et/ou humide. La quantité de particules passant le tamis le plus fin (ou étant solubles) a été estimée par la différence avec la matière sèche totale pesée avant le tamisage. La taille moyenne des particules a été calculée sur la base des moyennes pondérées du matériel retenu sur les tamis (MPSsieves) en tenant compte en plus du matériel perdu (MPStotal). L'analyse des mélanges par tamisage à sec a donné des MPSsieves de 0,58­2,90 mm et des MPStotal de 0,58­2,89 mm ; seule 0,02 à 2,71 % de la matière sèche a passé tous les tamis. L'analyse par tamisage humide de toutes les farines et des granulés a donné des MPSsieves similaires de 0,63­1,66 mm, mais des MPStotal nettement inférieurs de 0,26­1,04 mm ; entre 35 et 66 % de la matière sèche n'a pas été retenue sur les tamis. Les granulés présentaient des MPS plus faibles et une proportion plus élevée de particules passant par tous les tamis que les farines. Selon la référence utilisée, un maximum de 26 % des farines étaient conformes aux recommandations relatives à la taille des particules des aliments pour porcs. Aucun des aliments granulés ne répondait à ces critères, quelle que soit la source consultée pour la recommandation. Le tamisage humide devrait être considéré comme l'analyse standard car, dans le tamisage sec, les particules très fines adhérant à des particules plus grosses peuvent ne pas être enregistrées séparément mais contribuer de manière erronée au poids des particules plus grosses. En outre, le calcul du MPS devrait tenir compte de la matière perdue par le tamis le plus fin. Les raisons pour lesquelles les aliments pour porcs suisses ne répondent pas aux recommandations sur la taille des particules devraient être étudiées plus en détail.


Asunto(s)
Úlcera Gástrica , Enfermedades de los Porcinos , Alimentación Animal/análisis , Animales , Dieta , Tamaño de la Partícula , Úlcera Gástrica/veterinaria , Porcinos , Suiza
3.
J Dairy Sci ; 105(9): 7462-7481, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35931475

RESUMEN

Manure nitrogen (N) from cattle contributes to nitrous oxide and ammonia emissions and nitrate leaching. Measurement of manure N outputs on dairy farms is laborious, expensive, and impractical at large scales; therefore, models are needed to predict N excreted in urine and feces. Building robust prediction models requires extensive data from animals under different management systems worldwide. Thus, the study objectives were (1) to collate an international database of N excretion in feces and urine based on individual lactating dairy cow data from different continents; (2) to determine the suitability of key variables for predicting fecal, urinary, and total manure N excretion; and (3) to develop robust and reliable N excretion prediction models based on individual data from lactating dairy cows consuming various diets. A raw data set was created based on 5,483 individual cow observations, with 5,420 fecal N excretion and 3,621 urine N excretion measurements collected from 162 in vivo experiments conducted by 22 research institutes mostly located in Europe (n = 14) and North America (n = 5). A sequential approach was taken in developing models with increasing complexity by incrementally adding variables that had a significant individual effect on fecal, urinary, or total manure N excretion. Nitrogen excretion was predicted by fitting linear mixed models including experiment as a random effect. Simple models requiring dry matter intake (DMI) or N intake performed better for predicting fecal N excretion than simple models using diet nutrient composition or milk performance parameters. Simple models based on N intake performed better for urinary and total manure N excretion than those based on DMI, but simple models using milk urea N (MUN) and N intake performed even better for urinary N excretion. The full model predicting fecal N excretion had similar performance to simple models based on DMI but included several independent variables (DMI, diet crude protein content, diet neutral detergent fiber content, milk protein), depending on the location, and had root mean square prediction errors as a fraction of the observed mean values of 19.1% for intercontinental, 19.8% for European, and 17.7% for North American data sets. Complex total manure N excretion models based on N intake and MUN led to prediction errors of about 13.0% to 14.0%, which were comparable to models based on N intake alone. Intercepts and slopes of variables in optimal prediction equations developed on intercontinental, European, and North American bases differed from each other, and therefore region-specific models are preferred to predict N excretion. In conclusion, region-specific models that include information on DMI or N intake and MUN are required for good prediction of fecal, urinary, and total manure N excretion. In absence of intake data, region-specific complex equations using easily and routinely measured variables to predict fecal, urinary, or total manure N excretion may be used, but these equations have lower performance than equations based on intake.


Asunto(s)
Lactancia , Nitrógeno , Animales , Bovinos , Dieta/veterinaria , Fibras de la Dieta/metabolismo , Femenino , Estiércol , Leche/química , Nitrógeno/metabolismo , Urea/metabolismo
4.
J Dairy Sci ; 105(9): 7416-7431, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35931490

RESUMEN

Methane mitigation in dairy cows is an essential part of combating global warming. Governments and consumers have become increasingly interested in herbage-based feeding, and premium prices are often paid for these types of dairy products. However, this feeding strategy is presumed to produce more methane per unit of feed or milk than corn silage- or concentrate-based diets due to higher fiber intakes. Immature herbage is preferred to maintain dairy cow performance, but the high content of N and digestible fiber may increase methane and urine N emissions compared with more mature herbage. Tannin-containing feeds, such as vine leaves (Vitis vinifera), may help to combat the emissions associated with feeding immature herbage. Our study aimed to evaluate differences between early-stage (ES; 21 d of regrowth) versus late-stage (LS; 42 d) herbage and the effects of vine leaves on methane and nitrogenous emissions and the milk fatty acid profile of dairy cows. Twenty-four mid- to late-lactating dairy cows were randomized to 4 dietary groups (n = 6) in a factorial study design. Each of the 4 diets contained 69% fresh mixed legume-grass herbage, 13% grass hay, and 5% concentrate on a dry matter (DM) basis. Two diets were based on immature fresh mixed legume-grass herbage and grass hay (ES), and 2 contained more mature fresh mixed legume-grass herbage and grass hay (LS). Of these, 1 contained 13% vine leaves (VL+) and the other an additional 13% hay (VL-). No significant differences were observed in DM intake or milk yield across the diets. Methane emission intensity was lowest with ES-VL+ diets compared with LS-VL- diets (-30%; 17.1 vs. 24.5 mg/kg of energy-corrected milk). Methane yield decreased by 17% and 20% when related to the intake of DM and digested organic matter for ES-VL+ compared with LS-VL- diets (16.9 vs. 20.3 g/kg of DM intake; 23.5 vs. 29.3 g/kg of digestible organic matter). Immature grass and vine leaf addition each caused about half of the respective declines. Cows consuming any of the ES diets and the LS-VL+ diet consumed and excreted (urinary N) significantly more N than those consuming LS diets. However, when related to N intake, no differences were recorded. Unexpectedly, vine leaves did not mitigate urine N excretion; however, they lowered the n-6:n-3 ratio and increased concentrations of vaccenic and rumenic acids in both ES and LS diets. Our results demonstrate that feeding immature herbage in combination with vine leaves reduces methane yield; however, the associated high urinary N losses need to be addressed.


Asunto(s)
Metano , Leche , Animales , Bovinos , Dieta/veterinaria , Ácidos Grasos , Femenino , Lactancia , Nitrógeno , Hojas de la Planta , Ensilaje/análisis , Zea mays
5.
Br Poult Sci ; 63(5): 650-661, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35363105

RESUMEN

1. Due to the increasing global demand for more sustainably produced animal protein, there is an intensive search for feeds to replace soybeans. Black soldier fly larvae (BSFL) appear to have great potential for replacing soybeans in poultry diets. The main objective of this study was to determine if the nutritional value of BSFL is superior to soybeans when feeding organic broilers, since smaller amounts of BSFL could replace the soybean content in the feed, thus saving even more resources.2. Eighty Hubbard S757, a slow growing organic broiler type, were fattened for 63 d, spending the last 49 d on one of five diets. Two soybean cake- and soybean oil-based diets (SS, SS-) were compared with three diets based on partially defatted BSFL meal and BSFL fat from two origins (AA-, AB-, BB-). Different from diet SS, diets SS-, AA-, AB-and BB- were designed with approximately 20% less lysine and methionine. Growth (n = 16), metabolisability, body nitrogen retention, carcase and meat quality (n = 8) were evaluated.3. Broilers of the insect-based feeding groups, AA- and AB-, grew similarly well compared to those of group SS. They also retained more nitrogen in the body than those fed BB- and SS-. Breast meat yield was higher with AA- and AB- than with BB- and SS-, but still lower than with SS. Dietary variations in physicochemical meat quality were of low practical relevance. Diet BB- resulted in a more yellow skin and meat. The fatty acid profile of the breast meat lipids reflected the high lauric acid proportion of the BSFL lipids, resulting in up to 80 times higher proportions than when feeding the soybean-based diets.4. The results indicate that high-quality BSFL, depending on their origin, may indeed be superior to soybean protein, but that the meat lipids from BSFL-fed broilers can contain significant amounts of lauric acid, which, from a human nutrition perspective, could have a negative impact on meat quality.


Asunto(s)
Alimentación Animal , Glycine max , Animales , Alimentación Animal/análisis , Pollos , Dieta/veterinaria , Dípteros , Ácidos Grasos , Larva , Lisina , Carne/análisis , Metionina , Nitrógeno , Aceite de Soja , Proteínas de Soja
6.
Schweiz Arch Tierheilkd ; 164(4): 329-338, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35383030

RESUMEN

INTRODUCTION: The development of gastric ulcers in pigs has various reasons. In Switzerland, the last survey on the prevalence of gastric ulcers and possible risk factors was performed in 2005. We aimed to reassess gastric ulcers prevalence today, in 2021. A total of 1005 stomachs from fattening pigs from 136 batches and around 87 herds were evaluated at a Swiss abattoir. The Pars oesophagea of the stomach was scored from 0=healthy to 10=severe ulceration and strictures. Scores were compared between pigs produced under the labels «Integrierte Produktion Schweiz¼ (IPS, n=242 stomachs, 18 farms) and «Qualitätsmanagement-Schweizerfleisch¼ (QM, n=649, 58 farms) and others (n=114). The results showed a prevalence of 27,2 % mild mucosal changes (Scores 1-3), 14,9 % moderate mucosal changes (Scores 4-6) and 19,1 % severe mucosal changes (Scores 7-10). Only 38,8 % of the stomachs were rated 0 and thus considered healthy. Compared to the results from 2005, there is no difference concerning the lowest scores (0-2) and the highest scores (9-10). However, there was a shift from the medium scores (3-4) to higher scores (5-8). Stomach scores turned out to be herd specific. There were differences (p < 0,01) between labels, indicating that IPS pigs had less affected stomachs. Stomachs that were empty at slaughter showed higher scores (p < 0,001). The mean carcass weight of the pigs in the slaughter groups was negatively correlated (p < 0,05) to their median stomach score. Confiscations were not related to stomach scores. The results suggest that pig stomach health has not improved since 2005. The differences between labels seem to have resulted from different regulations prescribing a minimum particle size of enrichment material in IPS. The reasons for gastric ulcer development, including those on the individual herd within label, still have to be further clarified in order to allow targeted countermeasures. Given apparent farm-specificity, scoring of a limited number of stomachs per herd during the slaughter process could facilitate the establishment of a feedback scheme.


INTRODUCTION: Le développement d'ulcères gastriques chez les porcs a des causes diverses. En Suisse, la dernière enquête sur la prévalence des ulcères gastriques et les facteurs de risque possibles a été réalisée en 2005. Nous avons voulu réévaluer la prévalence des ulcères gastriques en 2021. Un total de 1005 estomacs de porcs d'engraissement provenant de 136 lots et d'environ 87 troupeaux ont été évalués dans un abattoir suisse. La Pars œsophagea de l'estomac a été notée de 0=sain à 10=ulcérations et sténoses sévères. Les scores ont été comparés entre les porcs produits sous les labels «Production Intégrée Suisse¼ (IPS, n=242 estomacs, 18 exploitations) et «Assurance Qualité Viande Suisse¼ (QM, n=649, 58 exploitations) et les autres (n=114). Les résultats ont montré une prévalence de 27,2 % de modifications muqueuses légères (scores 1­3), 14,9 % de modifications muqueuses modérées (scores 4­6) et 19,1 % de modifications muqueuses sévères (scores 7­10). Seuls 38,8 % des estomacs ont été classés 0 et donc considérés comme sains. Par rapport aux résultats de 2005, il n'y a pas de différence entre les scores les plus bas (0­2) et les scores les plus élevés (9­10). Cependant, on constate un glissement des scores moyens (3­4) vers les scores plus élevés (5­8). Les scores d'estomac se sont avérés être spécifiques au troupeau. Il y avait des différences (p < 0,01) entre les étiquettes, indiquant que les porcs IPS avaient des estomacs moins affectés. Les estomacs qui étaient vides à l'abattage présentaient des scores plus élevés (p < 0,001). Le poids moyen de la carcasse des porcs dans les groupes d'abattage était négativement corrélé (p < 0,05) à leur score gastrique médian. Les confiscations n'étaient pas liées aux scores gastriques. Les résultats suggèrent que la santé de l'estomac des porcs ne s'est pas améliorée depuis 2005. Les différences entre les labels semblent résulter de réglementations différentes prescrivant une taille minimale des particules de matériau d'enrichissement dans les IPS. Les raisons de l'apparition d'ulcères gastriques, y compris celles concernant un lot individuel au sein d'un label, doivent encore être clarifiées afin de permettre des contre-mesures ciblées. Étant donné l'apparente spécificité des exploitations, la notation d'un nombre limité d'estomacs par troupeau au cours du processus d'abattage pourrait faciliter l'établissement d'un système de retour d'information.


Asunto(s)
Úlcera Gástrica , Enfermedades de los Porcinos , Mataderos , Animales , Prevalencia , Úlcera Gástrica/epidemiología , Úlcera Gástrica/veterinaria , Porcinos , Enfermedades de los Porcinos/epidemiología , Suiza/epidemiología
7.
Poult Sci ; 100(4): 101034, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33662662

RESUMEN

Currently, there is a great interest in finding alternative protein and energy sources to replace soybean-based feeds in poultry diets. The main objective of the present study was to completely replace soybean in layer diets with defatted meal and fat from black soldier fly larvae without adverse effects. For this purpose, 5 × 10 Lohmann Brown Classic hens were fed either a soybean-based diet or diets based on defatted black soldier fly larvae meal and fat from 2 producers (1 commercial, 1 small-scale) operating with different rearing substrates, temperatures, and larvae processing methods (10 hens/diet). The data obtained included nutrient composition of larvae meals and diets, amino acid digestibility (6 hens/diet), and metabolizability, performance and egg quality (all 10 hens/diet). In addition, the acceptance of the 4 larvae-based diets was tested against the soybean-based diet in a 6-day choice feeding situation (10 hens/treatment). The nutritional value of the larvae-based diets was equivalent to the soybean-based diet in hens with a laying performance of 98%. Although average feed intake was not significantly different over the 7 experimental weeks, the diets based on larvae feeds from the small-scale production appeared to be slightly less accepted in a choice situation than the soy-based diet and those with larvae from commercial origin. This was more likely the effect of the larvae fat rather than that of the larvae protein meal. In addition, the commercial larvae material was superior to that from the small-scale production concerning supply with digestible sulfur-containing amino acids (548 vs. 511 mg/day) and lysine (792 vs. 693 mg/day), egg weight (67 vs. 63 g), daily egg mass (66 vs. 61 g/day) and, in tendency, feed efficiency. The results indicate that soybean-based feeds can be replaced completely by black soldier fly meal and fat in diets of high-performing layers. However, because of nutritional differences between the larvae materials of different origin the quality of the larvae has to be closely monitored before being used.


Asunto(s)
Dípteros , Glycine max , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Pollos , Dieta/veterinaria , Femenino , Larva , Comidas
8.
Appl Radiat Isot ; 166: 109381, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32987234

RESUMEN

- New estimates of partial α-decay half-life, T1/2, for 156-162,174,176Hf isotopes by a semi-empirical, one-parameter model are given. The used model is based on the quantum mechanical tunneling mechanism through a potential barrier, where the Coulomb, centrifugal and overlapping components to the barrier have been considered within the spherical nucleus approximation. This approach enables to reproduce, within a factor 2, the measured T1/2 of ground-state to ground-state (gs-gs) α-transitions for the artificially produced 156-162Hf isotopes. Half-life predictions for α-transitions from the ground-state of 159,161Hf isotopes to the first gamma-excited level of 155,157Yb isotopes are reported for the first time. The model also provides T1/2-values of (2.43±0.28)×1016 a and (1.47±0.19)×1020 a for the naturally occurring 174Hf and 176Hf isotopes, respectively, in quite good agreement with a number of estimates by other authors. In addition, the present methodology indicates that 174,176Hf isotopes exhibit α-transition to the first gamma-excited level of their daughter Ytterbium isotopes which half-lives are found (0.9±0.1)×1018 a and (0.72±0.08)×1022 a, respectively, with a chance of being measured by improved α-detection and α-spectrometry methods available nowadays.

9.
Animal ; 14(3): 538-548, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31576794

RESUMEN

Plant secondary compounds (PSC) are prevalent in many woody, temperate-climate plant species and play a crucial role in dietary attempts to mitigate methane emissions in ruminants. However, their application requires sufficient palatability and feeding value. In the present study, leaves from silver birch (Betula pendula), hazel (Corylus avellana), blackcurrant (Ribes nigrum), green grape vine (Vitis vinifera) and the herbs rosebay willow (Epilobium angustifolium) and wood avens (Geum urbanum) were tested in various doses with the Hohenheim gas test method in vitro and their short-term palatability in dairy cows. For the palatability experiment, the plants were pelleted with lucerne in different proportions to obtain the same phenol content, but realised contents differed from expected contents. The pellets were provided separately from a mixed basal ration (0.4 : 0.6) to each cow, in a randomised order, for 3 days per plant. All plants mitigated in vitro methane and ammonia formation, often in a linear dose response. These levels of effects differed among plants. Significant effects were observed at 100 (hazel, rosebay willow) to 400 g/kg of plant material. The test plants had a lower feeding value than the high-quality basal diet. This was indicated by in vitro organic matter digestibility, short-chain fatty acid formation and calculated contents of net energy of lactation. Simultaneously, the linear depression of ammonia formation indicated a dose-dependent increase of utilisable CP. Only blackcurrant and birch were less preferred to lucerne. However, this aversion subsided on day 3 of offer. The rosebay willow pellets had the highest phenol content but were not the least palatable. Accordingly, PSC may not be the main determinants of palatability for the plants tested. Plants did not differ significantly in their short-term effects on milk yield and composition, and all of the plants substantially reduced milk urea content. Overall, the results suggest that hazel and vine leaves, and rosebay willow and wood avens herbs should be tested for their potential to mitigate methane and N emissions in vivo.


Asunto(s)
Lactancia , Metano , Amoníaco/metabolismo , Animales , Bovinos , Dieta/veterinaria , Digestión , Femenino , Fermentación , Metano/metabolismo , Leche/química , Rumen/metabolismo , Ensilaje/análisis , Madera/química
11.
Pediatr Transplant ; 21(6)2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28649784

RESUMEN

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is the treatment of choice for a variety of congenital disorders. We report the experience of children affected by congenital diseases other than bone marrow failure syndromes who received allo-HSCT over a period of 25 years at G. Gaslini Paediatric Research Institute. HSCTs were performed in 57 children with congenital diseases (25 with congenital immunodeficiencies, 10 with severe combined immunodeficiencies, and 22 with metabolic diseases). Overall survival rate at 3 years in the whole group of patients was 76.9%, with a trend in favor of better outcome in children with metabolic diseases and in those who received cord blood cells (85.9%) vs bone marrow cells (72.4%).


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Síndromes de Inmunodeficiencia/terapia , Errores Innatos del Metabolismo/terapia , Adolescente , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Síndromes de Inmunodeficiencia/congénito , Síndromes de Inmunodeficiencia/mortalidad , Lactante , Recién Nacido , Estimación de Kaplan-Meier , Masculino , Errores Innatos del Metabolismo/mortalidad , Tasa de Supervivencia , Resultado del Tratamiento
12.
J Dairy Sci ; 100(2): 1331-1339, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27988131

RESUMEN

Dairy cow body size has increased over time because of breeding selection for higher milk yield, but milking stall dimensions have never been adjusted and are based on the practical experience of milking-machine manufacturers and advisory institutions. Narrow, limited milking stall dimensions might lead to behavioral changes during milking due to lack of comfort. The aim of this study was to examine the current space allowance in milking stalls on dairy farms and assess the effect of space allowance on cow behavior during milking. On 15 Swiss dairy farms, we measured clear milking stall dimensions and cow body dimensions. We calculated space ratios for length (SRlength) and width (SRwidth) by dividing the milking stall length or width by cow body length or belly width, respectively. When the space ratio was >1, we assumed that the body length or width of cow was smaller than the milking stall length or width. On each farm, 10 healthy cows were chosen for behavioral observation during 1 evening milking. We recorded rumination, elimination, and latency to enter the milking stall by direct observation. Hind leg activity was recorded using acceleration loggers. Data were analyzed using general linear mixed-effects models with farm as a random effect. Due to a strong collinearity between SRwidth and SRlength, we chose SRlength for further analysis, because it is based on skeletal characteristics. The SRlength was smallest in side-by-side parlors (1.07 ± 0.01) and largest in tandem parlors (1.18 ± 0.01). More cows had a tendency to ruminate with increasing SRlength (odds ratio: 1.8). None of hind leg activity, maximum peaks of hind leg accelerations, or latency to enter the milking stall were significantly affected by SRlength. Latency to enter the milking stall was longer for group milking parlors (side-by-side: 44.0 ± 3.2 s; herringbone: 34.3 ± 2.9 s) than for tandem parlors (19.0 ± 2.7 s). Milking parlor type had no effect on hind leg activity, maximum peaks of hind leg accelerations or rumination. The SRlength affected rumination behavior to some extent, indicating that cow comfort was positively affected by larger milking stall length. Because cow comfort is important for good milking performance, further investigations of milking stall dimensions for cow comfort and thus welfare are needed. Furthermore, the results showed that parlor type affected cow behavior, irrespective of SRlength, making future research necessary to identify the factors leading to this effect of parlor type.


Asunto(s)
Industria Lechera , Leche , Animales , Conducta Animal , Bovinos , Femenino , Lactancia
13.
Phys Chem Chem Phys ; 18(36): 25364-25372, 2016 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-27722644

RESUMEN

This paper reports on the morphological and electrical characterization at the nanometer scale and the investigation of the field emission characteristics of glassy carbon (GC) plates which underwent H-induced physical/chemical processes occurring in a dual-mode MW-RF plasma reactor. Plasma treatment produced on the GC surface arrays of vertically aligned conically shaped nanostructures, with density and height depending on the plasma characteristics. Two kinds of samples obtained under two different bias regimes have been deeply analyzed using an AFM apparatus equipped with tools for electric forces and surface potential measurements. The features of electron emission via the Field Emission (FE) mechanism have been correlated with the morphology and the structure at the nanoscale of the treated glassy carbon samples. The measured current density and the characteristics of the emission, which follow the Fowler-Nordheim law, indicate that the plasma-based methodology utilized for the engineering of the GC surfaces is able to turn conventional GC plates into efficient emission devices. The outstanding properties of GC suggest the use of such nanostructured materials for the assembling of cold cathodes to be used in a harsh environment and under extreme P/T conditions.

14.
J Nanosci Nanotechnol ; 15(2): 972-88, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26353603

RESUMEN

Nanodiamonds are a novel class of nanomaterials which have raised much attention for application in biomedical field, as they combine the possibility of being produced on large scale using relatively inexpensive synthetic processes, of being fluorescent as a consequence of the presence of nitrogen vacancies, of having their surfaces functionalized, and of having good biocompatibility. Among other applications, we mainly focus on drug delivery, including cell interaction, targeting, cancer therapy, gene and protein delivery. In addition, nanodiamonds for bone and dental implants and for antibacterial use is discussed. Techniques for detection and imaging of nanodiamonds in biological tissues are also reviewed, including electron microscopy, fluorescence microscopy, Raman mapping, atomic force microscopy, thermal imaging, magnetic resonance imaging, and positron emission tomography, either in vitro, in vivo, or ex vivo. Toxicological aspects related to the use of nanodiamonds are also discussed. Finally, patents, preclinical and clinical trials based on the use of nanodiamonds for biomedical applications are reviewed.


Asunto(s)
Microscopía Fluorescente/métodos , Nanocápsulas/química , Nanodiamantes/uso terapéutico , Prótesis e Implantes , Composición de Medicamentos/métodos , Nanocápsulas/ultraestructura , Nanodiamantes/química
15.
J Nanosci Nanotechnol ; 15(2): 1022-9, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26353608

RESUMEN

In this paper we present some strategies that are being developed in our labs towards enabling nanodiamond-based applications for drug delivery. Rhodamine B (RhB) has been choosen as model molecule to study the loading of nanodiamonds with active moieties and the conditions for their controlled release. In order to test the chemical/physical interactions between functionalized detonation nanodiamond (DND) and complex molecules, we prepared and tested different RhB@DND systems, with RhB adsorbed or linked by ionic bonding to the DND surface. The chemical state of the DND surfaces before conjugation with the RhB molecules, and the chemical features of the DND-RhB interactions have been deeply analysed by coupling DND with Au nanoparticles and taking advantage of surface enhanced Raman spectroscopy SERS. The effects due to temperature and pH variations on the process of RhB release from the DND carrier have been also investigated. The amounts of released molecules are consistent with those required for effective drug action in conventional therapeutic applications, and this makes the DND promising nanostructured cargos for drug delivery applications.


Asunto(s)
Nanocápsulas/química , Nanocápsulas/ultraestructura , Nanodiamantes/química , Nanodiamantes/ultraestructura , Rodaminas/análisis , Rodaminas/química , Espectrometría de Fluorescencia/métodos , Difusión , Composición de Medicamentos/métodos , Colorantes Fluorescentes/análisis , Colorantes Fluorescentes/química
16.
J Phys Condens Matter ; 23(47): 475302, 2011 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-22075922

RESUMEN

We compare, over wide temperature ranges, the transport properties of single-wall carbon nanotubes arranged in the form of aligned arrays or in the form of fibres. The experimental data show that both the forms of aggregates present a crossover in the transport mechanism from three-dimensional hopping of the electrons between localized states at high temperature to fluctuation-induced tunnelling across potential barriers at low temperature. The role of the junctions formed between the bundles in the array and between the nanotubes inside the fibres is discussed on the basis of the experimental results.


Asunto(s)
Conductividad Eléctrica , Nanotubos de Carbono , Temperatura , Impedancia Eléctrica , Fenómenos Magnéticos
17.
J Nanosci Nanotechnol ; 11(9): 8185-9, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22097552

RESUMEN

Deposits of individual diamond grains and continuous polycrystalline diamond layers have been generated by means of a HFCVD technique onto different types of untreated or seeded NbN surfaces. To test the feasibility of using diamond layers as protective coatings for aerospace applications, we carried out diamond deposition onto the lithographically defined NbN microelectrodes of a NbN/SiO2 multifinger device. The morphological and structural features of the diamond deposits and of the substrates were characterized by FE-SEM, XRD and Raman spectroscopy. The preferential growth of diamond on the superconductive NbN enables the selective coating of the NbN microstripes sputtered on the insulating SiO2. Moreover the diamond coating procedure is able to preserve the structural integrity of the substrate material and to retain the shaped architecture of the device. For the polycrystalline diamond layers grown on NbN a residual stress of -9.8 GPa, largely due to thermal stress, has been estimated by Raman analysis. The diamond coatings of the NbN-based architectures result to be mechanically stable.

18.
G Chir ; 31(8-9): 379-82, 2010.
Artículo en Italiano | MEDLINE | ID: mdl-20843441

RESUMEN

The authors want to present five cases (from May 1999 to May 2009) of acute abdomen from perforation of the foreign body introduced with food. They highlight how the accidental ingestion is very common but the perforation is rare. The preoperative diagnosis, in these cases, is always very difficult and the radiological examinations are not always able to resolve the diagnostic doubt with other acute intestinal diseases that are responsible of perforation. Then, the surgery procedure is, necessarily, the only possible diagnostic and therapeutic means. The mortality and the morbidity remain still high first of all for the delay in the diagnosis and the advanced age of patients.


Asunto(s)
Ciego/lesiones , Colon Sigmoide/lesiones , Migración de Cuerpo Extraño/complicaciones , Migración de Cuerpo Extraño/cirugía , Íleon/lesiones , Perforación Intestinal/etiología , Perforación Intestinal/cirugía , Abdomen Agudo/etiología , Anciano , Anciano de 80 o más Años , Femenino , Migración de Cuerpo Extraño/diagnóstico , Humanos , Perforación Intestinal/diagnóstico , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
19.
Scand J Immunol ; 71(1): 45-51, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20017809

RESUMEN

Surrogate markers for monitoring immuno-virological discordant responders, in addition to plasma viral load and CD4 cells, are still lacking. We assessed the diagnostic utility of CD38 expression on CD8 T cell assay, alone or in association with lymphocyte proliferation to mycotic antigens, in evaluating antiretroviral response. 28 vertically HIV-infected youths, 21 HAART- and seven 2 nucleotide reverse transcriptase inhibitors-treated, were enrolled in a retrospective study. Responders (57.1%) and non-responders (42.9%) to stable antiretroviral therapy for a minimum of 6 months, on the basis of viral load and CD4 T cells, comprehensively evaluated by CD38 expression on CD8 T lymphocytes [measured as CD38 antibody bound per CD8 T cell (CD38 ABC) and %CD38+ of total CD8 T cells (%CD38/CD8)] and lymphocyte proliferation to P. jiroveci, C. albicans, C. neoformans, A. fumigatus at a single time point after treatment, were selected. CD38 expression > or =2401 CD38 ABC and > or =85% CD38/CD8 cut-off points, accurately discriminates responders versus non-responders, both measures resulting in 75.0% (CI 42.8-94.5) sensitivity (identification of non-responder) and 93.8% (CI 69.8-99.8) specificity (identification of responder), when considered as single assays. The association '> or =2401 CD38 ABC or > or =85% CD38/CD8' improved sensitivity to 83.3% (CI 51.6-97.9), while the association '<2401 CD38ABC (or <85% CD38/CD8) and lymphoproliferative response positive to > or =2 tested organisms' improved specificity to 100% (CI 79.4-100). In conclusions, CD38 expression and mycotic antigen-specific T-cell proliferation may be used as additional parameters to existing criteria to evaluate antiretroviral response in immuno-virological discordant patients.


Asunto(s)
ADP-Ribosil Ciclasa 1/fisiología , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Linfocitos T CD8-positivos/inmunología , VIH-1 , Glicoproteínas de Membrana/fisiología , ADP-Ribosil Ciclasa 1/análisis , Síndrome de Inmunodeficiencia Adquirida/inmunología , Síndrome de Inmunodeficiencia Adquirida/virología , Adolescente , Antígenos Fúngicos/inmunología , Terapia Antirretroviral Altamente Activa , Niño , Femenino , Humanos , Activación de Linfocitos , Masculino , Glicoproteínas de Membrana/análisis , Curva ROC
20.
J Nanosci Nanotechnol ; 9(3): 2124-7, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19435091

RESUMEN

Electrochemical Double Layer Capacitors (EDLC), also known as supercapacitors, have been fabricated using Single Walled Carbon Nanotubes (SWCNTs) as active material for electrode assembling. In particular a new way of fabrication of ultra-thin electrodes (< or = 25 microm) directly formed on the separator has been proposed, and a prototype of EDLC has been realized and tested. For such devices the specific capacitance is in the range 40-45 F/g and the internal resistances in the range 6-8 omega x cm2, at current density of 2 mA x cm-2.

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