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1.
Animal ; 17(10): 100982, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37797494

RESUMO

The routine use of intramammary antimicrobial products in all dairy cows at the beginning of the dry period is no longer allowed in European Union (EU) countries due to the new Regulation (EU) 2019/6 to reduce antimicrobial resistance. This study investigated the application of a selective dry cow therapy scheme and the risk factors of high individual milk somatic cell count (SCC) and individual neutrophil count in early lactation, as a response to the application of a selective dry cow therapy (SDCT) protocol. The study was carried out on three commercial farms, and a total of 243 lactating cows were monitored at the end of lactation and at the beginning of the next one, 91 of which were dried off without the use of antimicrobials (NoT) based on milk SCC, differential somatic cell count (DSCC), and the response of Vetscan DC-Q milk analyser, using a secret algorithm. The remaining 152 cows received antimicrobials (T). After calving, similar means were observed between the two treatment groups for SCC (4.8 vs 4.9 log10 cells/ml for T and NoT, respectively, P = 0.5) and total milk leucocyte count (TLC) (5 vs 5.1 log10 cells/ml for T and NoT, respectively, P = 0.7) in milk. However, the use of antimicrobials led to a lower DSCC (58 vs 64% for T and NoT, respectively, P = 0.01) and lower percentage of neutrophils (59 vs 64% for T and NoT, respectively, P = 0.05), although the levels of DSCC and percentage of neutrophils in cows dried off without antimicrobials remained lower than the risk threshold suggested by the international literature. A logistic regression was computed after the application of selective dry cow therapy to identify risk factors of high milk SCC (≥100 000 cells/mL) at the beginning of lactation. Increased milk SCC after calving was related to high SCC at the end of lactation and abandonment of antimicrobial therapy at dry-off. Moreover, the length of the dry period, milk protein content, and flank cleanliness in the last test day before dry-off were other factors in the logistic regression. Neutrophil counts at the beginning of the next lactation were affected by the same factors that influenced SCC, together with milk production, TLC, and macrophages on the last test day. The results obtained in these studied farms showed that selective dry cow therapy may be applied without adversely affecting the next lactation.


Assuntos
Anti-Infecciosos , Doenças dos Bovinos , Mastite Bovina , Feminino , Bovinos , Animais , Lactação/fisiologia , Mastite Bovina/tratamento farmacológico , Glândulas Mamárias Animais , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Contagem de Células/veterinária , Fatores de Risco , Antibacterianos , Indústria de Laticínios/métodos
2.
Sci Total Environ ; 905: 166845, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37709092

RESUMO

One popular methodology for assessing the environmental impact of livestock sector is Life Cycle Assessment (LCA), that quantifies the environmental impact of a product. Ecological Footprint (EF) performs an environmental sustainability assessment, by comparing the demand for natural capital by an economic activity with the offer of such capital within a certain territory. The aim of the study was the comparison between LCA and EF in assessing the environmental performances of milk production, assuming as case study three cattle farms with increasing levels of production intensity. Different metrics and functional units (FU) (i.e., fat and protein corrected milk, FPCM and hectare) were adopted for LCA analysis, considering some of the major impact categories. For greenhouse gases emissions, the Global Warming Potential (GWP) and the Global Temperature Potential (GTP) were considered. Both metrics were calculated assuming or not the distinction between biogenic and fossil methane. Adopting GWP as a metric, the results per kg of FPCM provided by the LCA highlighted a different trade off compared to the EF method: the farm with the highest productive intensity produced the least impactful milk in terms of GWP but had the most negative Ecological Balance (EB). The same occurred for the other impact categories. When GTP was adopted, or the hectare was considered as FU, the least intensive farm, characterized by greater feed self-sufficiency, became the one that produced the least impactful milk and had the least negative EB. The study highlighted the scientific significance of the integration between the two approaches for creating a comprehensive representation of the effects of human activities on the environment. The LCA method evaluates impacts intensity referred to a specific functional unit and its results are strongly influenced by productive efficiency; the EF method evaluates environmental sustainability of productions in relation to the territory that supports them.


Assuntos
Biodiversidade , Indústria de Laticínios , Humanos , Animais , Bovinos , Indústria de Laticínios/métodos , Temperatura , Leite , Estágios do Ciclo de Vida , Guanosina Trifosfato
3.
Animal ; 16(11): 100650, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36220000

RESUMO

The rising global demand for animal products and the growing public concerns about the environment and animal welfare require dairy farms to improve their efficiency and apply more sustainable farming systems. Precision Livestock Farming (PLF) could represent a valuable support in addressing these challenges. In recent years, dairy farms have been modernising and introducing new sensors and automatic systems for managing the herd. However, the diffusion of new technologies in Italian dairy farms is still limited and farmers are reluctant to invest in precision systems. The aim of the study was to investigate the presence of PLF tools in Italian dairy farms, the motivations, benefits and limits of technological investments from the farmers' point of view and the factors affecting the diffusion of technology. From November 2020 to June 2021, an online questionnaire was distributed and 52 responses were obtained. About 79% of the farms were located in Lombardy. The more represented milking system was the conventional milking parlour (73%), followed by automatic milking (19%). The average age of respondents was quite low: 35% of them was less than 40 years old and more than 50% was between 40 and 60. Statistical analyses were performed to evaluate the effects of different factors on the presence of technology at farm. The age of the farmer, the milk production level and the presence of an automatic milking system influenced the technological level of the farm. Precision systems that provide information on animal activity for the management of reproduction and on milk yield and flow are the most popular and are considered among the most useful. Management of reproduction and milk production are the areas where farmers appear to show interest for future investments as well. Younger farmers appear to have implemented more PLF systems than older ones, and they show a propensity to invest in latest generation precision tools. Farmers seem to have a growing interest in PLF, but some limits have been identified: the investment costs, followed by the lack of time to check information from sensor systems and the difficulty in data interpretation. As PLF technologies can play an important role in the development of sustainable, animal-friendly and efficient livestock production, further improvements and efforts are necessary to increase the propensity to PLF of dairy farmers. Results can be useful in the Italian context but also in other countries where dairy farming is rapidly intensifying but PLF is encountering resistance.


Assuntos
Indústria de Laticínios , Gado , Bovinos , Animais , Fazendas , Indústria de Laticínios/métodos , Leite , Fazendeiros , Agricultura , Tecnologia
4.
J Dairy Sci ; 103(5): 4863-4873, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32113778

RESUMO

The aim of the present study was to evaluate, through a survey conducted on commercial farms, the global warming potential (GWP) of different lactating cow total mixed rations (TMR) and to identify the best dietary strategies to increase feed efficiency (FE) and reduce enteric CH4 emission. A total of 171 dairy herds were selected: data about dry matter intake (DMI), lactating cow TMR composition, and milk production and composition were provided by farmers. Diet GWP (kg of CO2 equivalents; CO2eq) was calculated as sum of GWP (kg of CO2eq) of each included ingredient, considering inputs needed at field level, feed processing, and transport. For soybean solvent meal, land use change was included in the assessment. Enteric methane production (g/d) was estimated [using the equation CH4 (g/d) = 2.54 + 19.14 × DMI] to calculate CH4 emission for kilograms of fat- and protein-corrected milk (FPCM). The data set was analyzed by generalized linear model and logistic analysis using SAS 9.4 (SAS Institute Inc., Cary, NC). The frequency distribution showed wide variation among farms for GWP (kg of CO2eq) of TMR: approximately 25% of the surveyed farms showed a diet GWP of 15 kg of CO2eq, 20% showed a GWP of 13 kg of CO2eq, and 16.7% showed a GWP of 17 kg of CO2eq. The variation among farms was due to the feedstuffs used. Among feedstuffs, soybean meal (SBM) had the highest correlation with the GWP of the TMR as shown by the following equation: TMR GWP (kg of CO2eq) = 2.49 × kg of SBM + 6.9 (R2 = 0.547). Moreover, diets with inclusion of SBM >15% of dry matter (DM) did not result in higher milk production than diets with a lower inclusion of SBM (≤15%). Average daily milk production of cows was 29.8 [standard deviation (SD) 4.83] kg with fat and protein contents of 3.86% (SD 0.22) and 3.40% (SD 0.14), respectively. The average DMI (kg/d) of lactating cows was 22.3 (SD 2.23). Logistic analysis demonstrated that corn silage ≤30% of diet DM was associated with higher FE. Almost 50% of farms had an average value of 15.0 g of CH4/kg of FPCM and about 30% of farms had an average of 12.5 g of CH4/kg of FPCM. The results demonstrated that lower enteric CH4 production was related to inclusion (% of diet DM) of ≤12% alfalfa hay and >30% corn silage. Diets with >34% neutral detergent fiber had higher CH4 production (>14.0 g/kg of FPCM) than those with lower neutral detergent fiber content. In contrast, lower enteric CH4 production (≤14.0 g/kg of FPCM) was related to diets characterized by net energy of lactation (NEL) >1.61 Mcal/kg and >4% ether extract. The variability in TMR GWP shows significant potential for reducing the GWP of a diet through choice and inclusion levels of ingredients (mainly SBM) and the possibility of decreasing methane enteric emission associated with milk production on a commercial scale.


Assuntos
Ração Animal , Bovinos/metabolismo , Dieta/veterinária , Lactação , Metano/metabolismo , Animais , Feminino , Itália , Leite , Rúmen/metabolismo , Silagem , Glycine max , Inquéritos e Questionários , Zea mays
5.
Meat Sci ; 145: 447-454, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30055437

RESUMO

The aim of this trial was to analyse the environmental impact of the rabbit production system, through a cradle to-slaughterhouse gate using a life cycle approach. Since in a rabbit farm the production efficiency depends on the feed conversion and quantity of meat produced, scenarios characterized by different slaughter weights and dissimilar level of mortality during the fattening phase were hypothesized. Climate change determined in the standard rabbit resulted in 3.86 kg CO2 eq/kg live weight, slightly higher than that of broilers and not different from that of pork. High and Low mortality scenarios resulted in impact changes from +5.22 and -2.31%, respectively, compared with the standard system. An increase of environmental impact values (up to 36%) was registered when live weight enhanced from 2.7 to 2.9 kg for standard and heavy rabbits. The results obtained underline the strict link between the ability to convert feed into meat and the environmental sustainability of meat production also in the rabbit system.


Assuntos
Matadouros , Ração Animal , Criação de Animais Domésticos , Peso Corporal , Mudança Climática , Conservação dos Recursos Naturais , Carne , Animais , Dieta , Meio Ambiente , Humanos , Indústria de Embalagem de Carne , Coelhos
6.
Sci Total Environ ; 626: 1200-1209, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29898527

RESUMO

The dairy sector is recognised as one of the most impacting agricultural activities. In Italy approximately 24% of cow's milk is destined to Grana Padano, a Protected Designation of Origin long ripening cheese. The Grana Padano production has increased by 10% in the last decade and approximately reached 183,000 t in 2015. Around 38% of this production is exported to Germany, US, France and to the rest of the world. This study evaluated the environmental impact of production of Grana Padano, through a "cradle to cheese factory gate" Life Cycle Assessment. The study involved an Italian cheese factory that produces about 3.6% of the total production of Grana Padano cheese and a group of 5 dairy farms, chosen among the farms that sold all milk produced to the cheese factory. The functional unit was 1 kg of Grana Padano cheese 12-month ripened. Environmental impacts of co-products: whey, cream, butter and buttermilk were also evaluated. Two sensitivity analyses were conducted: the first one had the aim to explore the effect of different allocation methods based on dry matter content, economic or nutritive value of cheese, respectively; the second one considered the variation of the impacts of milk production and its effect on cheese environmental impact. Milk production phase gave the most important contribution to the environmental impact of cheese, with a percentage of 93.5-99.6% depending on the impact category. Excluding milk production from the system boundary, milk transport and use of electricity were the main responsible of the environmental impact of cheese-making process. The climate change impact for the production of 1 kg Grana Padano was 10.3 kg of CO2 eq, using a dry matter allocation method, while 16.9 and 15.2 kg of CO2 eq adopting economic and nutritive value allocation methods, respectively.

7.
J Dairy Sci ; 97(7): 4579-93, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24792806

RESUMO

The intensification process of the livestock sector has been characterized in recent decades by increasing output of product per hectare, increasing stocking rate, including more concentrated feed in the diet, and improving the genetic merit of the breeds. In dairy farming, the effects of intensification on the environmental impact of milk production are not completely clarified. The aim of the current study was to assess the environmental impacts of dairy production by a life cycle approach and to identify relations between farming intensity and environmental performances expressed on milk and land units. A group of 28 dairy farms located in northern Italy was involved in the study; data collected during personal interviews of farmers were analyzed to estimate emissions (global warming potential, acidification, and eutrophication potentials) and nonrenewable source consumption (energy and land use). The environmental impacts of milk production obtained from the life cycle assessment were similar to those of other recent studies and showed high variability among the farms. From a cluster analysis, 3 groups of farms were identified, characterized by different levels of production intensity. Clusters of farms showed similar environmental performances on product basis, despite important differences in terms of intensification level, management, and structural characteristics. Our study pointed out that, from a product perspective, the most environmentally friendly way to produce milk is not clearly identifiable. However, the principal component analysis showed that some characteristics related to farming intensification, such as milk production per cow, dairy efficiency, and stocking density, were negatively related to the impacts per kilogram of product, suggesting a role of these factors in the mitigation strategy of environmental burden of milk production on a global scale. Considering the environmental burden on a local perspective, the impacts per hectare were positively associated with the intensification level.


Assuntos
Indústria de Laticínios/métodos , Meio Ambiente , Leite/metabolismo , Animais , Bovinos , Conservação de Recursos Energéticos , Conservação dos Recursos Naturais , Eutrofização , Feminino , Aquecimento Global , Itália , Lactação
8.
Eur J Clin Microbiol Infect Dis ; 28(1): 95-8, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18663498

RESUMO

This study performed a retrospective analysis on the relationship between blood culture time-to-positivity (TP) and type of isolated microorganism, antibiotic administration, and immunological status of the patients. We analyzed the data related to 1,218 positive blood cultures. When compared to Gram positive bacteraemia, the percentage of Gram negative growth was higher and the mean TP significantly shorter (p < 0.0001). In patients receiving antibiotics, median and mean TPs of blood culture were different for Gram positive bacteraemia (log-rank p = 0.0022, Wilcoxon p < 0.0001) but not for Gram negative (log-rank p = 0.4011, Wilcoxon p = 0.1585). No statistically significant effect on TP was found for sampling site, interaction between sampling site and antibiotic administration, and immunological status of the patient. In conclusion, TP is independent of antibiotic therapy in cases of Gram negative bacteraemia, while for Gram positive bacteraemia a prolongation of TP occurs.


Assuntos
Antibacterianos/uso terapêutico , Bacteriemia/diagnóstico , Bacteriemia/tratamento farmacológico , Sangue/microbiologia , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Adulto , Hospitais , Humanos , Neoplasias/complicações , Estudos Retrospectivos , Fatores de Tempo
9.
J Colloid Interface Sci ; 319(1): 160-8, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-18096179

RESUMO

The dispersion behavior of clusters of hydrophilic and hydrophobic silica treated with a thermoresponsive polymer has been investigated. The influence of the thermoresponsive interfacial chemistry was assessed by performing dispersion studies in poly(dimethylsiloxane) (PDMS) at 25 and 68 degrees C for agglomerates of powders incorporating poly(N-isopropyl acrylamide) (PNIPAM), a thermoresponsive polymer, and water. While the dispersion of clusters of hydrophilic silica was found to be temperature independent, dispersion of hydrophobic silica exhibited a temperature dependency. The response of the polymer upon temperature variation brings about modifications in the interparticle interactions of the PNIPAM-treated powders thus leading to changes in the cluster cohesivity. The dependence of the cluster cohesivity on temperature was evidenced through changes in the dispersion mechanism and kinetics of the treated silica clusters at both tested temperatures. In addition, optical microscopy of silica suspensions with and without PNIPAM at 25 and 60 degrees C, illustrated the effect of the polymer presence and configuration on the particle-particle interaction forces. While micrographs of the particles at 25 degrees C show less evidence of particle aggregation, the micrographs at 60 degrees C illustrate an increase in aggregation suggesting an enhancement in the attractive forces between particles.

10.
Minerva Stomatol ; 56(10): 481-95, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18091665

RESUMO

AIM: To analyze the data collected in 13 years of clinical controls in patients with oral rehabilitation on Bone System dental implant systems and to evaluate the success, failure and complications in daily implant dentistry, without strict inclusion criteria, in order to define the success or survival or failure of dental implants. METHODS: A total of 477 patients (231 men and 246 women) received dental implants for oral rehabilitation in 3 different private dental offices in Piedmont, Italy. A total of 1 021 fixtures were implanted from 1992 to 2004; patients were followed up for a maximum of 13 years. Surgery was performed by the same operator using the same dental implant system (Bone System, Italy), with manufacturer modifications and improvements to the system as it evolved during the study period. Treatment planning and oral reconstruction on the inserted implants were carried out by 3 different specialists in prosthesis dentistry and 4 dental laboratory technicians. In the follow-up period, clinical success was defined as the degree of patient satisfaction and as the survival of restorations on dental implants. RESULTS: The survival rate of the fixtures was 95.9%; the clinical effectiveness was 92.8%; the failure rate was 4.1%. Complications included peri-implantitis, implant fractures and technical complications related to implant components and prostheses. Long-term implant survival and clinical success were not influenced by anatomic site (maxilla or mandible). CONCLUSION: Dental implant therapy is a viable option for oral rehabilitation; if correctly managed, it may provide predictable results.


Assuntos
Prótese Dentária Fixada por Implante , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Estudos Retrospectivos , Fatores de Tempo
11.
J Dairy Sci ; 90(3): 1159-67, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17297090

RESUMO

The study of milk flow curves provides useful information for enhancing milking efficiency and protecting udder health by adapting milking machine and milking procedures to the physiological requirements of the cow. The aim of this experiment was to investigate, using field data, the relationships among traits of the milk flow curves, their sources of variation, and milking performances in terms of milk production, machine-on time, and udder health. A total of 2,486 milk flow curves of the whole udder were collected in 82 Italian Holstein-Friesian dairy herds in the Lombardy region of Italy. Approximately one-third (35.1%) of milk flow curves were classified as bimodal. Most flow characteristics were influenced by lactation number, days in milk, and peak flow but also strongly affected by premilking operations. Proper udder preparation, including forestripping and predipping, resulted in better milking performances compared with poor preparation, with greater milk yield per milking, shorter milking time, and lesser bimodality. Premilking delay time, between the start of teat stimulation and cup attachment, affected milking time significantly: The shortest milking time was obtained for a range of delay time between 1 and 60 s. As the delay time increased, the percentage of bimodality dropped significantly. Increasing the number of clusters per operator led to greater percentages of bimodal curves. The greater somatic cell count of cows with bimodal curves supports the hypothesis of the negative effect of bimodality on udder health and indicates the importance of avoiding its occurrence using proper pre-milking procedures.


Assuntos
Bovinos/fisiologia , Indústria de Laticínios/métodos , Lactação/fisiologia , Glândulas Mamárias Animais/fisiologia , Leite/metabolismo , Animais , Indústria de Laticínios/instrumentação , Feminino , Análise dos Mínimos Quadrados , Fatores de Tempo
12.
J Dairy Sci ; 84(11): 2450-9, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11768086

RESUMO

The objective of the experiment was to compare a silage-based control diet (C) with a nonforage diet (NF) in dairy goats throughout lactation in terms of animal performance and energy utilization. Eight Saanen goats were divided into two groups and fed C or NF, a commercial blend that included sunflower meal, cassava, coconut meal, and whole cottonseeds as the main ingredients that was characterized by a small particle size and a high crude protein content. In early, mid, and late lactation (44, 100, and 219 days in milk) the goats were individually tested for dry matter intake (DMI), digestibility, milk yield and composition, milk renneting properties, rumen and plasma parameters, and nitrogen and energy utilization (open circuit respiration chambers). During early and mid lactation, the NF fed goats had a very high DMI: 2946 and 2915 g/d, respectively. Nevertheless, milk yield was similar for the two treatments: 4369 vs. 4342 and 3882 vs. 3841 g/d for goats fed diets C and NF during the first and second periods, respectively. Milk fat content was not statistically different between the two diets. The protein content and rheological parameters of milk were similar for the two diets. Nonprotein nitrogen and urea levels in milk of goats fed NF were significantly higher than goats fed C. Ruminal ammonia and plasma urea nitrogen were also significantly increased by diet NF, due to its high protein content. Plasma glucose, beta-hydroxybutyrate, and nonesterified fatty acids and ruminal volatile fatty acids were not influenced by dietary treatment. Dietary NF significantly decreased energy digestibility (74.5 vs. 65.8%, on average for the lactation, for C and NF, respectively) and had a significantly lower metabolizability (metabolizable energy/intake energy; 66.6 vs 58.0%, on average); however, the efficiency of utilization of metabolizable energy was unaffected by the diet. In conclusion, goats were fed a nonforage diet during the entire lactation without detrimental effect on their health and productive performance.


Assuntos
Ração Animal/análise , Cabras/fisiologia , Leite/metabolismo , Nitrogênio/metabolismo , Animais , Nitrogênio da Ureia Sanguínea , Peso Corporal , Ingestão de Energia , Metabolismo Energético , Feminino , Lactação , Leite/química , Fatores de Tempo
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