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1.
Alessandro Marchetti Chiara Piccini Sergio Santucci Igino Chiuchiarelli Rosa Francaviglia 《CATENA》2011,85(3):267-273
Soil surveys are an essential source of information for land management although a limited budget often reduces the amount of data available. Even if the dataset is limited, geostatistics can provide a valid estimation tool through a weighted moving average interpolation (kriging). Often, however, the spatial variability of soil properties appears smoothed and short range variability is underestimated by this kind of interpolation technique. A more realistic distribution of a given variable on the territory can be obtained through models based on stochastic simulation. 相似文献
2.
S. Morandi M. Brasca R. Lodi L. Brusetti C. Andrighetto A. Lombardi 《Research in veterinary science》2010,88(3):427-435
The study concerns 130 Staphylococcus aureus strains isolated from different raw-milk dairy products (122 isolates) and human samples (eight isolates). Four different typing techniques were applied: biochemical profiles (Biolog GP), restriction fragment length polymorphism of coagulase gene (coaRFLP), random amplified polymorphic DNA (RAPD) and multilocus variable number tandem repeat analysis (MLVA). Moreover multiplex-PCR was used to study the distribution of genes encoding staphylococcal enterotoxins. The results of this study reveal marked genomic and phenotypic variability among the tested S. aureus. The considered techniques were all found useful for strain typing, but, based on discriminatory power as the key parameter of the typing system, MLVA and Biolog GP were found to be the most powerful techniques. The methods showed little concordance in terms of discerning the clusters of related strains. 相似文献
3.
Gottardo F Mattiello S Cozzi G Canali E Scanziani E Ravarotto L Ferrante V Verga M Andrighetto I 《Journal of animal science》2002,80(9):2362-2372
Growth performance, behavior, physiology, forestomach development, abomasal lesions, and meat quality of veal calves fed a milk-replacer diet (No Water) were compared to those obtained from calves fed the same diet and provided with increasing amounts of drinking water (Water). Two groups of 69 Polish Friesian calves, balanced according to initial BW, were assigned to two water treatments in a 3 x 2 x 2 factorial arrangement that provided solid feed in addition to the milk-replacer diet (No solid feed, 250 g x calf(-1) x d(-1) of wheat straw or the same amount of beet pulp), and the adoption of two housing systems (individual stall vs group pen). The fattening trial lasted 160 d, and calves received drinking water starting from the 2nd wk of the study. The amount of drinking water was progressively increased from 3 to 8 L x cal(-1) x d(-1). Although not dehydrated, as shown by hematocrit and Na, K, and total protein hemoconcentration, calves consumed almost all the offered amount of water throughout the fattening period. Therefore, the water provided by the milk replacer alone, which ranged between 6 to 16 L calf d(-1), was not sufficient to satisfy the need of the animal. Drinking water did not affect the calves' growth performance but it reduced nonnutritive oral behavior throughout the fattening period. Based on these results, drinking water did not cover a shortage in the calves' water requirement but it played a role in environmental enrichment. Health status was similar between treatments, although water provision reduced the episodes of feed refusal. The measurement of chronic stress by ACTH challenge showed that the administration of drinking water would be advisable when calves are fed with small amounts of solid feed for well-being. Feces consistency and animal cleanliness were not affected by drinking water. At slaughter, forestomach development was similar between treatments, and drinking water did not affect the number of calves showing rumen hair-balls and abomasal lesions. No differences in color and other meat quality traits were observed between Water and No Water calves. Despite the lack of direct effects on productive traits, when water was available, the calves drank it, and positive effects were noticed on their nonnutritive oral behaviors and chronic stress indicators. 相似文献
4.
Gabai G Cozzi G Rosi F Andrighetto I Bono G 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2002,49(2):73-80
To assess the leptin response to metabolic challenges, three Italian Simmental cows were infused for 6 h: with (a) saline (control); (b) glucose; and (c) amino acid solutions according to a 3 x 3 Latin square experiment. The infusions were carried out at the 36th week of pregnancy, and the second and 12th week of the following lactation. At each of the three infusion periods, blood samples were collected from the jugular vein before and 15, 30, 120, 180, 240, 300 and 360 min after the beginning of each infusion. All samples were analysed for leptin, insulin, glucagon, growth hormone (GH), glucose, non-esterified fatty acids (NEFA) and urea. The physiological phase of the cows significantly affected the basal concentrations of insulin, glucagon, urea and NEFA. The infusion of both glucose and the amino acid solutions did not affect leptin concentrations. Insulin response was significantly increased when animals were infused with the glucose solution and, within treatment, the greatest response was observed at the 12th week of lactation. The greatest glucagon response was observed when infusing the amino acid solution. Urea response to all treatments increased from the dry period to the 12th week of lactation. The GH and NEFA responses were not affected by treatments. The Multi Species radio-immunoassay used in this study showed a lower sensitivity for ruminant leptin which may partially explain the lack of significant leptin variations. However, it can be hypothesized that leptin variations around parturition can be affected by the negative energy balance, and leptin release is not acutely affected by glucose and amino acid availability. In addition, no short-term relationship were found between insulin, glucagon and GH and leptin release in Italian Simmental cows during the dry period and early lactation. 相似文献
5.
Vascellari M Pozza G Poppi L Capello K Angeletti R Ravarotto L Andrighetto I Mutinelli F 《The Veterinary record》2008,163(5):147-151
The histological status of the thymus, blood cortisol concentration and circulating neutrophil:lymphocyte ratio were evaluated in 349 slaughtered beef cattle, to assess the potential of these parameters as indirect biomarkers of the illegal use of corticosteroids in meat production. The livers of 20 of the animals were analysed chemically for residues of corticosteroids. The morphology of the thymus was examined for adipose tissue infiltration, cortical atrophy and 'starry sky' appearance, and on the basis of these characteristics, the animals were considered to be negative, suspected or positive for illegal corticosteroid treatment. The animals considered to be negative had a mean cortisol concentration that was significantly higher (29 ng/ml) than that of the animals suspected for corticosteroid treatment (22 ng/ml). Using the chemical analysis as the gold standard for identifying illegally treated animals, the histological examination of the thymus had a sensitivity of 100 per cent and a specificity of 85 per cent. The samples that were positive by chemical analysis had cortisol concentrations of less than 2.0 ng/ml, whereas the mean cortisol concentration of the negative samples was 10.3 ng/ml. 相似文献
6.
R. De Nardi G. Marchesini A.‐L. Stefani A. Barberio I. Andrighetto S. Segato 《Journal of animal physiology and animal nutrition》2014,98(3):504-510
The particle size of cereal grains has been found to modulate the rate of passage from the rumen and the digestibility of starch and neutral detergent fibre (NDF), but few studies have examined its impact on reticular pH. The study aimed to evaluate the effect of feeding finely ground maize on the risk of ruminal acidosis, milk yield and composition. Twelve Holstein‐Friesian cows were assigned to one of two experimental groups and fed according to a cross‐over design. Diets were isoenergetic and isonitrogenous and were characterised by the same NDF and ADF, differing only in maize particle size. In the control diet (Ct), the maize meal was ground to 1.0 mm, whereas in the experimental diet, it was finely ground (Fg) to 0.5 mm. The pH and temperature of the reticulum were continuously measured in eight cows throughout the trial using indwelling sensors. Dry matter intake was higher in cows offered Fg diet than in Ct (19.0 vs. 20.3 kg/day; p = 0.067). However, milk yield (p = 0.855) and the 3.5% fat‐corrected milk (FCM) (p = 0.724) did not show any differences between the diets. Casein (2.48 vs. 2.57%; p = 0.035) and crude protein (CP) (3.18 vs. 3.31%; p = 0.021) resulted higher in Fg. Similarly, starch digestibility increased in animals offered Fg diet versus Ct (0.94 vs. 0.98; p = 0.078). Among the reticular parameters, the Fg‐fed cows spent a significantly higher time below the 5.5 pH threshold (15 vs. 61 min/day; p = 0.047) and had an average daily variation in reticular pH characterised by a lower nadir pH (5.95 vs. 5.72; p < 0.001) and a higher pH range (0.79 vs. 0.94; p = 0.003). In this study, grain particle size affected the risk of the onset of ruminal acidosis. Therefore, it should be carefully considered when formulating rations. 相似文献
7.
Wei acid digestion is commonly used for the elemental analysis of the labile (i.e. organic, exchangeable plus soluble) pool in organic soil horizons. However, this method is not entirely specific for this pool in samples containing mineral admixtures. In this study, these admixtures are found to release significant amounts of elements, although these admixtures are highly quartzitic. A statistical evaluation of ash and element concentrations shows that, for a wide range of ash concentrations, only for phosphorus and calcium reliable concentrations of their labile pool were obtained. Acid extraction after dry ashing showed to produce somewhat better results at low ash concentrations, but suffered from large overestimations at high ash contents as well. Therefore, elemental analyses in element dynamics studies merit a critical consideration of the digestion technique used. Implications of overestimations for such studies are discussed. 相似文献
8.
I. Andrighetto P. Berzaghi G. Cozzi F. Gottardo M. Zancan 《Journal of Agronomy and Crop Science》1997,179(4):251-256
Spring cut Italian ryegrass was harvested at two different stages of maturity: lake vegetative (EARLY) and flowering (LATE). The wilted forage was round baled and then ensiled by wrapping in plastic film. EARLY harvest reduced dry matter (DM) yield significantly as compared to LATE (5.6 vs. 10.5 t ha−1 ; P < 0.01). However, forage quality both before and after ensiling was better for EARLY with higher crude protein (CP) and non-structural carbohydrates content and a lower amount of cell walls (NDF). Higher pH and the fermentation characteristics confirmed the poor quality of LATE silage, having higher content of butyrate, propionate and acid detergent insoluble nitrogen and a lower concentration of lactic acid.
Dry matter intake of EARLY silage by sheep (average 65.0 ± 7.3 kg LW) fed solely forage ad libitum was 37 % higher than LATE (1386 vs. 1011 g DM day−1 ; P < 0.05) due to its better palatability and digestibility. In vivo DM digestibility of EARLY silage was 76.1 % while it decreased to 58.2 % for LATE silage. Estimated metabolizable energy content of EARLY silage (11.5 MJ kg−1 DM) was 29 % higher than LATE (8.9 MJ kg−1 DM) resulting as similar to the reference value of a high quality perennial ryegrass silage. The forage conservation system of ensiled round bales is effective and recommended when spring cut Italian ryegrass is harvested at an early stage of maturity. 相似文献
Dry matter intake of EARLY silage by sheep (average 65.0 ± 7.3 kg LW) fed solely forage ad libitum was 37 % higher than LATE (1386 vs. 1011 g DM day
9.
Morgante M Stelletta C Berzaghi P Gianesella M Andrighetto I 《Journal of animal physiology and animal nutrition》2007,91(5-6):226-234
Subacute rumen acidosis (SARA) represents one of the most important metabolic disorders in intensive dairy farms that affects rumen fermentations, animal welfare, productivity and farm profitability. The aim of the present study was to study the occurrence of SARA in intensive Italian dairy herds and to determine the relationship between diet composition, ruminal pH and short chain fatty acids (SCFA) concentration. Ten commercial dairy herds were investigated; twelve cows in each herd were selected randomly among animal without clinical signs of disease, with good body condition and between 5 and 60 day-in-milk (DIM), to perform rumenocentesis and obtain rumen fluid. Ruminal pH was determined immediately after sampling and concentration of SCFA in ruminal fluid was determined on samples after storage. An other objective of this research was to study in detail the effects of rumenocentesis on animal health: this study could confirm the extreme validity of this technique as ruminal sampling. Results were subject to anova and correlation analysis using SIGMA STAT 2.03. The results indicated the presence of SARA in three herds (more than 33% cows with rumen pH < 5.5), a critical situation (more than 33% cows with rumen pH < 5.8) in five farms and a normal rumen pH condition in two herds. In particular, dairy herds show on average SCFA concentration of 150, 145, 123 mmol/l for low pH, critical pH and normal pH herds respectively. There were not significant differences among diet composition even if herds with SARA showed a light discordance between initially chemistry composition and residual feed. In the affected herds it was not possible to understand the exact causes of SARA. Animal management seems to be one of the most important factors in developing SARA including total mixed ration preparation. 相似文献
10.
Multivariate analysis of heat tolerance characteristics in Santa Inês and crossbred lambs in the Federal District of Brazil 总被引:1,自引:1,他引:0
Marilma Pachêco Chediak Correa Bruno Stéfano Lima Dallago Samuel Rezende Paiva Maria Eugênia Andrighetto Canozzi Helder Louvandini Júlio Jardim Barcellos Concepta McManus 《Tropical animal health and production》2013,45(6):1407-1414
Heat tolerance is an important trait for deciding on which genetic resource to use on farms in tropical regions. Three genetic groups of lambs were evaluated by physical and physiological parameters related to adaptation and multivariate analyses used to test if these traits were efficient in separating the genetic groups and which traits were more important in this separation. Crossbred lambs were more similar to each other than to Santa Inês, in general; but individually there was an overlap between Ile de France and Santa Inês lambs. Size traits had higher canonical correlation with physiological variables, while rectal temperature, heart rate, and hemoglobin were more highly correlated with physical traits. Error rates using only physiological traits were high, suggesting that these are inefficient in separating groups of lambs for heat tolerance, while separation with physical traits was more efficient. 相似文献