709 research outputs found
Performance evaluation of LoRa networks in a smart city scenario
No full textLow-Power Wide Area Networks (LPWANs) are continuously gaining momentum as fundamental enablers of the Internet of Things (IoT) paradigm. These networks provide longrange coverage to end nodes, exploiting license-free frequency bands. The focus of this work is on one of the most prominent LPWAN technologies: LoRaTM. We implemented a new ns-3 module to study the performance of a LoRa-based IoT network in a typical urban scenario. Simulation results show that a LoRa network can scale well, achieving packet success rates above 95% in presence of a number of end devices in the order of 10 4
Short communication: The relationship between dietary particle size and undegraded neutral detergent fibre in lactating dairy cows: A prospective cohort observational study
No full textPhysically effective NDF (peNDF) and undegraded aNDF at 240 h (uNDF.240) are important parameters for characterizing NDF in fibre evaluation and are associated with dietary physical form and fibre digestibility characteristics. A new concept that combines peNDF and uNDF.240, physically effective uNDF.240 (peuNDF.240 = pef × uNDF.240), was recently established. The peuNDF.240 value allows determination of dry matter intake (DMI), and the productive response of cows even in the absence of variation in DMI or when cows are fed rations with low uNDF.240 and high peNDF or rations with high uNDF.240 and more finely chopped fibre. The aim of this study was to improve our understanding of the relationships between dietary uNDF.240 content to other fibre fractions, average cow DMI, gross feed efficiency, and milk yield at the farm level. Furthermore, the relation between peuNDF.240 and the productive response of cows was also investigated at the farm level. In the Po’ Valley, which is a representative area for dairy production in Italy, a cohort of 22 Holstein dairy farms was monitored over two years (2019–2020). Information regarding average cow DMI, milk yield, and ration composition was obtained through interviews with farmers, and feed samples were collected and chemically analysed. Farms were classified according to their dietary uNDF.240 (% of DM) content: low (uL) ≤ 8.29 or high (uH) > 8.29. Farms with low dietary uNDF.240 used less alfalfa forage as a fibre source compared with farms with high dietary uNDF.240 (6.27 vs. 15.5 % of DM) and showed higher average milk yield (35.9 vs. 33.6 kg/cow/day, respectively) and similar DMI (23.9 vs. 24.3 kg/cow/day, respectively). Dietary peuNDF.240 was negatively related to milk yield (milk yield = 47.4 – 1.87 peuNDF.240, R2 = 0.62, adjusted R2 = 0.60, residual standard error (RSE) = 1.87, P = 0.001) and gross feed efficiency (gross feed efficiency = 1.96 – 0.08 peuNDF.240, R2 = 0.65, adjusted R2 = 0.64, RSE = 0.07, P = 0.001). The results of this study have practical significance for farmers, as they suggest that the inclusion of low digestible forages in the ration (i.e., late-harvested alfalfa characterized by high uNDF.240) may require more fine shredding to reduce the overall value of peuNDF.240 and increase cow production
Effect of Inoculants and Sealing Delay on the Fermentation Quality of Early Harvested Wheat Forage
No full textSimple Summary: Winter cereal silages are becoming a crucial component of dairy nutrition for Mediterranean countries, partially replacing maize silage even in high-producing cows. Concerns regarding the definition of their final quality and the potential for aerobic deterioration, leading to loss of dry matter, feed intake, and milk yield, need to be investigated. We evaluate the effect of different ensiling conditions, including the use of inoculants and freshly harvested plant composition, on the final silage quality, and the most relevant risk factors associated with the silage's aerobic deterioration. The dry matter at harvest affected the entire final silage quality, and acetic acid varies between the control (pure water) and the hetero-/homofermentative. The aerobic stability for all samples was 59.2 +/- 23.6 h without statistical differences within the thesis, ensuring a sufficient time for a convenient silo unload rate. Winter cereal silages can suffer from an inadequate fermentative path which can lead to aerobic instability. We evaluate the pre-ensiled conditions influencing the final fermentative quality and its aerobic stability. We studied the use of hetero/homofermentative inoculants on two early-harvest wheat samples (312 and 348 g/kg of dry matter-DM levels) undergoing three ensiling delays. The fermentative profiles were evaluated during the first ten d of ensiling, at 60 d and after 7 and 14 d of aerobic exposure. Aerobic stability was recorded during fourteen d after the silo opening. Significant (p < 0.05) differences of the final fermentative profile were related mainly to DM levels at harvest, while the use of the inoculant affected only the acetic acid significantly. Finally, the sealing delay did not significantly affect the silage fermentative profile. The overall aerobic stability was 59.2 +/- 23.6 h, and cumulative temperatures were lower than 438 for seven d of aerobic exposure and higher than 1526 for 14 d. Although the homofermentative inoculants reduced the counts of yeasts in the final silage for the earlier harvested wheat, the other samples showed yeasts counts of similar to 4.9 Log10 colony-forming units/g, with the presence of spoilage fungi (Pichia and Geotricum)
Assessment of the effectiveness of a portable NIRS instrument in controlling the mixer wagon tuning and ration management
No full textThe adoption of the mixer wagon and total mixed ration aimed to decrease dysmetabolic diseases and improve feed efficiency in dairy cows. Differences between theoretical and eaten diets are imputable to errors in diet preparation or cow feed sorting. We proposed a method to measure the chemical composition and particle size distribution of the ration and determined its peNDF content through a portable Near Infra-Red spectrophotometer that allowed the calculation of two indexes: the homogeneity and the sorting indexes. In a cohort of 19 Italian Holstein breeding farms, we studied the correlation of these indexes with the mixer wagon settings. Determination coefficients in the validation (Rv2) for dry matter, crude protein, aNDF, and starch were 0.91, 0.54, 0.86, and 0.67, respectively. The ration fractions (%, w/w of wet weight) retained by the 3.8 and 1.8 mm sieves, and the bottom showed Rv2 of 0.46, 0.49, and 0.53, respectively. The homogeneity index regressed negatively with the mixer wagon load fullness (R2 = 0.374). The homogeneity-binary classification showed an odds ratio of 1.72 for dry matter and 0.39 for aNDF (p < 0.05). The sortingbinary classification showed an odds ratio of 2.54 for aNDF (p < 0.05). The studied farms showed low peNDF values (median = 17.9%)
Prevalence of gastrointestinal, liver and claw disorders in veal calves fed large amounts of solid feed through a cross-sectional study
No full textThe impact of the current practice of feeding veal calves with large amounts of solid feed (SF) on the prevalence of specific disorders on rumen, abomasum, liver and claws was investigated through a post-mortem inspection at the abattoir. Forty-one batches (“batch” referred to a group of calves of the same breed, coming from the same farm and belonging to the same slaughter group) of crossbred male calves from dairy breed were randomly inspected at 213.6 days old. On average 16.0 rumens, 15.6 abomasa, 15.1 livers, and 30.5 hind claws were checked per batch. Rumens were evaluated for the presence of hyperkeratosis and plaques; abomasa for the presence of lesions in the pyloric area; livers for the presence of lipidosis, abscess or fibrous adherence; and claws for the presence of sole hemorrhages. More than 60% of rumens per batch had signs of hyperkeratosis and plaques, and 80 to 100% of abomasa per batch showed at least 1 lesion in the pyloric area. On average 24% of livers per batch were diseased and about 65% of claws per batch had sole hemorrhages. Affected abomasa were positively correlated to rumens with plaques. Claws with sole hemorrhages tended to be positively correlated to rumens with hyperkeratosis. Calves of inspected batches were fed 311 ± 31 kg DM/cycle of milk-replacer and 158 ± 44 kg DM/cycle of SF containing more than 85% of corn grain. Based on the recorded prevalence of alterations, this feeding strategy should be reconsidered in order to improve veal calves' welfare
Wider slot in pens with fully slatted rubber mat flooring for fattening bulls: Effects on animal hygiene, health and welfare
No full textThis study investigated health and welfare of 119 Swedish fattening bulls when allowing wider slots in fully slatted rubber mats pens. On arrival Light bulls (around 120 ± 28 kg at 4.7 ± 1.3 mo of age) were allotted to 6 pens with fully slatted rubber mats, of which 3 Control pens had 30 mm slot openings and 100 mm slat width and 3 Test pens had 35 mm slot openings and 90 mm slat width. Reaching >400 kg (Heavy bulls), Control bulls were moved to 3 larger pens having 35 mm slot openings and 100 mm slat width and Test bulls to 3 pens having 40 mm slot openings and 100 mm slat width. Pens hosted 5–7 bulls. Bulls stayed in the same group (Control/Test), and were observed until slaughter (around 600 kg for 20.5 ± 2.1 mo). Total drainage area was 14% for Control and 18% for Test floors. Bull body condition, hygiene, locomotion and leg lesions were assessed on eight days during the 18 months study. At slaughter, hind feet were measured, trimmed, and evaluated for claw disorders. Two pens/floor were filmed during two 14-h sessions to monitor animal activities, social interactions, and lying postures. Wider slots did not affect body condition or hygiene on farm, although 3 Control and 1 Test bulls were penalised at slaughter for poor hygiene. Light bulls were dirtier than Heavy bulls, especially on thigh/flank areas. Bulls became dirtier in winter. Percentage of bulls showing locomotor problems was generally low and not affected by wider slots (1.09 vs. 0.91% for Control and Test bulls, respectively). Test bulls showed a slight tendency to develop more swelling on hock and carpus (0.55 vs. 3.18% for Control and Test bulls, respectively). Rubber mats did not cause toe overgrowth (mean dorsal wall of outer claw = 87.5 mm) and Test bulls showed lower prevalence of asymmetric claws (38.5 vs. 13.3% for Control and Test bulls, respectively). Interdigital hyperplasia and white line fissure were detected only in Control bulls. Outcomes of this study suggested that the 4%-unit increase in drainage area of fully slatted rubber mat floors did not impair bull behaviour, since few atypical transitions and lying sequences were recorded, or even improve flooring and animal hygiene. However, some limitations of the research require further investigations to provide evidence supporting the widening of slot openings in fully slatted rubber mat floors for fattening bulls’ welfare purpose
Hoof cortisol variation in calves during the neonatal period.
No full textThe neonatal period is a critical phase of the animal’s life cycle. The hoof in the neonatal period undergoes significant changes. The claw incorporates endogenous hormones that passively diffuse from capillaries to the hoof matrix during keratinisation over a longer time period. The aim of this study was to characterize hoof cortisol concentrations in 20 calves at 30 and 60 days of age. The samples were obtained from the front right hooves during claw trimming. The clipped sole samples obtained had the thickness of 0.5–0.7 mm and, according to the rate of hoof growth, represent the endocrine milieu for approximately 1 month before trimming. Cortisol concentrations of freeze-dried clipped claw samples were evaluated by RIA after extraction with methanol. Hoof cortisol levels in calves decreased (p < 0.05) from the first to the second month of life. Because hoof cortisol detected at 30 days of age represents the cumulative effect of parturition and neonatal adaptation, the significant decrease trend suggests the progressive ability of calves to cope with the environment through the allostasis, a process promoted by body systems including the hypothalamic-pituitary-adrenal axis. This preliminary study showed that hoof can be used to measure cortisol, a hormone that could have an influence on the bovine claw’s physiology
An insight into the dairy chain of a Protected Designation of Origin cheese: The case study of Asiago cheese
No full textThe Protected Designation of Origin (PDO) label of the European Union safeguards and guarantees top-quality traditional agri-food products that must be manufactured in a specific region according to traditional production methods. Production specifications of PDO cheeses are often focused on the cheese-making process and lack information on the dairy farming system that is upstream of the chain. This case study aimed to analyze and cluster the dairy farms that supply milk to the chain of Asiago, an internationally known PDO cheese of northeastern Italy. A large survey involving all of the cheese factories of the Asiago PDO chain was made in 2017. Each cheese factory submitted a questionnaire to its supplying dairy farmers concerning (1) farm facilities and herd management and (2) feeding program of lactating cows. Results from 517 farms were processed; there were 67 ± 27% (mean ± standard deviation) respondents per cheese factory. Four clusters of dairy farms were identified by hierarchical clustering analysis. Cluster 1 (8% of the surveyed farms) and cluster 2 (22%) are small in size and low in yield, representing the traditional milk production system; farms are mainly located on mountains or hills and have autochthonous dual-purpose breeds mostly housed in tiestall barns. By rearing cattle of endangered breeds and feeding cows primarily with forages produced on-farm together with the use of pasture, these clusters, and especially cluster 1, have shown to provide essential ecosystem services for landscape and biodiversity preservation in the alpine areas. Clusters 3 and 4 (34 and 36% of the surveyed farms, respectively) gather medium-scale farms mainly located in the lowland that operate according to modern management and housing systems and rear high-producing dairy cows. These cows are mainly fed total mixed rations based on corn silage, but the dietary forage:concentrate ratio is kept relatively high, as farmers are more interested in producing high-quality milk for cheese-making than pushing for yield. Regardless of the cluster allocation, a considerable cow longevity, which is a recognized “iceberg indicator” of cattle well-being, was highlighted. This study showed that different farming systems may lay behind a single PDO cheese. The knowledge of their characteristics is important to reinforce the PDO production specifications as well as to distinguish and protect niche products that come from specific groups of farms that provide essential ecosystem services
Spectral features of 21 Lutetia, target of Rosetta mission
No full textThe International Rosetta Mission, successfully
launched on March 2nd 2004, will encounter
comet 67P/Churyumov-
Gerasimenko, the principal target of the
mission, in 2014. During its long journey
Rosetta will fly-by also two asteroids: 2867
Steins (September 2008) at a distance of
about 1700 km and at a relatively low speed
of about 9 kilometers per second and 21 Lutetia
(July 2010) at about 3000 km at a speed
of 15 kilometers per second.
Rosetta will try to answer to the main questions
related to the origin and evolution of the
Solar System as minor bodies contains the
record of the chemical, physical and dynamical
primordial processes of the formation of
our planetary system.
In this work we present the analysis of two
visible spectra of Lutetia taken at NTT-ESO,
Chile, in order to confirm the presence of
absorption bands previously determined on
other spectra of the asteroid (Lazzarin et al.,
A&A, 2004).In particular, we investigated the spectral region
where these bands were detected by using
a higher spectral resolution. We confirm
a broad complex feature between 0.45
and 0.55 micron and two narrower features
around 0.47 and 0.52 micron which possible
origin will be discussed.
A more precise knowledge of the surface
composition of Lutetia is particularly
important for the definition of the observational
strategy of the Rosetta mission
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