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Rearing conditions, morbidity and breeding performance in dairy heifers in southwest Sweden 总被引：1，自引：1，他引：0
We carried out a longitudinal study of 122 dairy herds in southwest Sweden to investigate relationships of rearing conditions and health with heifer breeding performance and to estimate the incidence of clinical diseases and survival until 1st calving. A total of 3081 animals born in 1998 (47% Swedish Red; 50% Swedish Holstein breed) were followed from birth until calving, culling or death. Information about housing, management, breeds and dates of birth, breeding and calving was obtained from farmers. Diseases were recorded by farmers and veterinarians; antibiotic treatment was used in <25% of all cases.Median time to breeding was 17.5 months, 64% of all heifers bred by AI conceived at 1st breeding, and median time to calving was 27.6 months. Age at 1st breeding (log-transformed), conception at 1st breeding (binary), and age at 1st calving (log-transformed) were analysed with three mixed models, accounting for clustering by considering random-intercept and random-slope effects at the herd level. Around 40 potential predictors or confounders were recorded and considered for modelling. Time to breeding and calving increase greatly with the time heifers spend grazing, although up to 5 months of grazing before 1st calving appears to be more favourable than no grazing at all. The effect of grazing differs depending on the season of birth. Zero-grazed heifers calve 20% later if exposed to indoor ammonia concentrations >10 ppm after start of breeding. There is considerable variation between herds in breeding performance, except for conception at 1st breeding—limiting the potential for improving conception by herd measures.Observed total disease incidence rate was 14 per 100 animal-years from 7 months of age to estimated conception and 4.7 per 100 animal-years from conception to calving, with great variation between herds. Infectious diseases were predominant, and diarrhoea, respiratory disease and ringworm were the most common diagnoses. Eight hundred and fifty-three heifers left the study before calving, due to herd exits (incidence risk 0.073%), selling off live (0.061%), spontaneous deaths (0.050%) or slaughter (0.092%). 相似文献
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Siqueira Thamires Damascena Quirino dos Santos Monnerat João Paulo Ismério Chagas Juana Catarina Cariri da Conceição Maria Gabriela de Siqueira Michelle Christina Bernardo Viana Thays Bianca Lira de Andrade Ferreira Marcelo 《Tropical animal health and production》2019,51(7):1975-1980
Tropical Animal Health and Production - The objective of this study was to evaluate the nutritional value of different roughage sources as an exclusive feed for goats and sheep from the... 相似文献
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Maria Filipa Castanheira Sonia Martínez Páramo F. Figueiredo Marco Cerqueira Sandie Millot Catarina C. V. Oliveira Catarina I. M. Martins Luís E. C. Conceição 《Fish physiology and biochemistry》2016,42(5):1441-1452
Individual differences in behaviour and physiological responses to stress are associated with evolutionary adaptive variation and thus raw material for evolution. In farmed animals, the interest in consistent trait associations, i.e. coping styles, has increased dramatically over the last years. However, one of limitations of the available knowledge, regarding the temporal consistency, is that it refers always to short-term consistency (usually few weeks). The present study used an escape response during a net restraining test, previously shown to be an indicative of coping styles in seabream, to investigate long-term consistency of coping styles both over time and during different life history stages. Results showed both short-term (14 days) consistency and long-term (8 months) consistency of escape response. However, we did not found consistency in the same behaviour after sexual maturation when the restraining test was repeated 16, 22 and 23 months after the first test was performed. In conclusion, this study showed consistent behaviour traits in seabream when juveniles, and a loss of this behavioural traits when adults. Therefore, these results underline that adding a life story approach to data interpretation as an essential step forward towards coping styles foreground. Furthermore, a fine-tuning of aquaculture rearing strategies to adapt to different coping strategies may need to be adjusted differently at early stages of development and adults to improve the welfare of farmed fish. 相似文献
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Inês Rocha Ying Ma Maria F. Carvalho Catarina Magalhães Martina Janoušková Miroslav Vosátka 《Archives of Agronomy and Soil Science》2019,65(1):31-43
Arbuscular mycorrhizal (AM) fungi and plant growth-promoting rhizobacteria, responsible for enhancing plant nutrition, vigour and growth, may be used to reduce dosages of chemical fertilisers. Technologies that allow an economically viable and efficient application of these beneficial microbes in large scale agriculture must be studied. Seed coating is a potential delivery system for efficiently introducing minor amounts of bioinoculants. Despite the dramatic reduction on inoculum dose per plant, inoculation of AM fungi via seed coating was as effective as conventional soil inoculation. Fertilisation and inoculation had a significant impact on maize shoots nutrient concentrations. Different fertilisation regimes did not influence mycorrhizal colonisation. Plants without fertilisation and singly inoculated with R. irregularis showed shoot nutrient concentration increments of 110, 93, 88 and 175% for nitrogen, phosphorus, potassium and zinc, respectively, comparing with non-inoculated controls. Plants singly inoculated with P. fluorescens via seed coating under full fertilisation, presented enhancements of 100, 75 and 141% for magnesium, zinc and manganese, respectively, comparing with non-inoculated controls. Seed coating is a promising tool for delivering microbial inoculants into the soil, while promoting sustainable production of maize. This technology is particularly pertinent in low input agriculture, with potential environmental profits and food quality improvements. 相似文献
66.
Ribeiro Hugo da Silva Joana Gomes Jesus João Magalhães Catarina Dias Joana M. Danko Anthony S. 《Journal of Soils and Sediments》2019,19(1):439-450
Purpose
Biodiesel is a renewable fuel that can be mixed with toluene and be accidentally released into anoxic ecosystems and impact soil microbial communities. Therefore, the aim of the present work was to examine, under nitrate-reduction conditions, the biodegradation of toluene in the presence of two different types of biodiesel (sunflower and rapeseed), and their impact on the bacterial community structure.
Materials and methodsSediment samples were spiked individually with toluene, biodiesel, and their blends in laboratory-designed microcosms. Sunflower oil biodiesel was produced in the laboratory, while rapeseed oil biodiesel was a commercial product. Degradation of biodiesels and blends was monitored by directly measuring the substrate or indirectly by determining nitrate removal during the course of the experiment. Denitrification rates were estimated with the acetylene inhibition technique. Denaturing gradient gel electrophoresis was used to assess impacts on the bacterial community structure exposed to biodiesels, blends, and toluene.
Results and discussionThe results of this study showed that toluene and biodiesel were completely degraded within 10 days. Biodiesel significantly affected the bacterial community structure at a similar magnitude, independently of its origin. Additionally, toluene impacted the bacterial community and denitrification process to a lower extent than biodiesel and a clear decrease in the relative bacterial richness and diversity was shown in samples with biodiesel and blends. To the best of our knowledge, this is one of the first reports describing degradation of biodiesel alone and blends under nitrate-reducing conditions, and also the effects of these compounds on the denitrification process. In addition, due to the recently discovered “oxygenic denitrification” process, the acetylene inhibition technique and nitrous oxide quantification may not be the most adequate tool to estimate denitrification rates. Further detailed studies are advised to understand whether the identified bacterial community shift impacts ecosystem functions.
ConclusionsOur results help to understand the biodegradation of toluene, biodiesel, and their blends in sediments under nitrate-reducing conditions and might be important in implementing bioremediation strategies in anoxic environments.
相似文献67.
Catarina C. V. Oliveira Filipe Figueiredo Florbela Soares Wilson Pinto Maria Teresa Dinis 《Fish physiology and biochemistry》2018,44(3):885-893
The present study reveals the first characterization of the plasma melatonin rhythms of the meagre (Argyrosomus regius) under aquaculture conditions. Melatonin levels were monitored during a 24 h cycle under a photoperiod of 16 L:8D and under constant darkness (DD), respectively to characterize the daily rhythm of this indoleamine and to test its endogenous origin. Besides, to identify which light intensities are perceived as night or day by this species, the degree of inhibition of nocturnal melatonin production caused by increasing intensities of light was tested (3.3, 5.3, 10.5, and 120 μW/cm2), applying 1 h light pulses at Mid-Dark. The result for melatonin daily rhythm in plasma showed a typical profile: concentration remained low during all daytime points, increasing greatly during dark points, with maximum values at 16:00 and 22:00 h, zeitgeber time. Under DD conditions, the plasma melatonin profile persisted, with a similar acrophase but with a lower amplitude between subjective day and night periods, indicating this rhythm as being endogenously driven. Moreover, meagre seemed to be very sensitive to dim levels of illumination during the night, since an intensity of just 3.3 μW/cm2 inhibited melatonin production. However, only the pulse of 5.3 μW/cm2 caused a melatonin drop till daytime concentrations. Thus, the threshold of light detection by the pineal organ was suggested as being located between 3.3 and 5.3 μW/cm2. Such results are an added value for this species biology knowledge, and in consequence to its adaptation to aquaculture conditions, allowing the improvement of culture husbandry protocols. 相似文献
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The aim of this study is to justify that the drying rate of wood can be represented by a phenomenological model defining a driving force expressed as the difference between the average wood moisture content and the equilibrium wood moisture content. The results show that the mathematical relation proposed is valid when introducing an overall mass transfer coefficient, K, at low temperature wood-drying rates. 相似文献
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Clia M. Teixeira Priscila M. Silva Rita Gamito Sandra Amoroso Nuno Lopes Catarina Freitas Henrique N. Cabral Jos L. Costa 《Fisheries Oceanography》2020,29(3):276-289
The beach‐seine fishery is a commercial fishing activity on the Portuguese coast, with reports dating as far back as the early 15th century. The main target species of this fishery are small pelagic fish such as Atlantic chub mackerel, Atlantic horse mackerel and sardine. To identify the best conditions for fishing the target species, catches of beach seine (2007–2017) were used and generalized linear models were applied, using a binomial and gamma distributions. The logistic model explained between 36.3% and 45.7% of the catches variability; the gamma model explained 9.1% and 46.9% of the catches variability, being month and wind direction the best covariates for the occurrence and/or abundance of the three small pelagic fishes in analysis. If the effort is directed to the days that meet the conditions found for each species (sardine: between May and October, wind NW, daytime; Atlantic horse mackerel: May, NW/NE wind, 800 m from the coastline; Atlantic chub mackerel: from July to August, NW moderate wind), a reduction in bycatch and discards can be achieved. This approach can have a positive economic and social impact, since it provides information for turning fisheries more efficient. 相似文献
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Ivone Figueiredo Catarina Maia Lucília Carvalho 《Fisheries Management and Ecology》2020,27(5):454-463
The undulate ray Raja undulata Lacepède is a coastal species common along the north‐eastern Atlantic Ocean and Mediterranean Sea and is highly accessible to coastal fisheries. Between 2009 and 2015, the species was under a European Union (EU) fisheries moratorium that hampered the collection of data to assess its stock status in Portuguese waters. After that period, a small experimental EU fishing quota was set for Portugal enabling collection of fishery data under a fishermen self‐sampling scenario. Based on the data collected, R. undulata abundance was estimated along the Portuguese continental coast through the application of a N‐mixture model and incorporating environmental factors. The results support the species coastal and patchy nature across the study area with higher abundances estimated in areas associated with shallow sandy bottoms as the Southwest region. The present work constitutes an important step for the management of this fishery resource, in particular concerns about its abundance trends over time and its spatial distribution and habitat requirements. 相似文献