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1.
J Dairy Res ; 90(3): 269-272, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37691620

RESUMO

This research communication describes a pilot study measuring skin carotenoid levels of lactating dairy cows. Carotenoids are natural antioxidants, involved in cell communication and immune function, protecting against oxidative stress. They are precursors of vitamin A, important for reproduction efficiency, growth and male fertility. Therefore, easy-to-use, inexpensive methods to measure carotenoids in cattle would provide interesting data for farmers to monitor the health and nutritional status of their herds. In this study, we used a commercially available sensor based on multiple spatially resolved reflection spectroscopy (MSRRS), intended for human use, to measure the carotenoid content in bovine skin in three research herds in France, Ireland and Scotland. Carotenoid levels were measured by applying the sensor to the teat barrel, avoiding pigmented areas of skin. Mean sensor values differed significantly between herds and between diets, with pasture-based animals showing significantly higher carotenoid levels. Our results suggest that MSRRS can be used to accurately to measure skin carotenoids in cows. However, further calibration in bovines is needed to improve of the accuracy of the MSRRS sensor in cattle.


Assuntos
Carotenoides , Lactação , Feminino , Bovinos , Masculino , Animais , Humanos , Lactação/fisiologia , Projetos Piloto , Dieta/veterinária , Análise Espectral/métodos , Análise Espectral/veterinária
2.
Sensors (Basel) ; 19(5)2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30866541

RESUMO

The reticuloruminal function is central to the digestive efficiency in ruminants. For cattle, collar- and ear tag-based accelerometer monitors have been developed to assess the time spent ruminating on an individual animal. Cattle that are ill feed less and so ruminate less, thus, the estimation of the time spent ruminating provides insights into the health of individual animals. pH boluses directly provide information on the reticuloruminal function within the rumen and extended (three hours or more) periods during which the ruminal pH value remains below 5.6 is an indicator that dysfunction and poor welfare are likely. Accelerometers, incorporated into the pH boluses, have been used to indicate changes in behaviour patterns (high/low activity), utilised to detect the onset of oestrus. The paper demonstrates for the first time that by processing the reticuloruminal motion, it is possible to recover rumination periods. Reticuloruminal motion energy and the time between reticuloruminal contractions are used as inputs to a Support Vector Machine (SVM) to identify rumination periods with an overall accuracy of 86.1%, corroborated by neck mounted rumination collars.

3.
J Ext ; 53(2)2015.
Artigo em Inglês | MEDLINE | ID: mdl-29520118

RESUMO

Washington state dairy producers were surveyed to determine pest and parasite prevalence and range of current pest management strategies. Nearly all respondents reported treating their cattle or premises for flies, while 62% reported treating their animals for external parasites. Use of pyrethroid and pyrethrins insecticides was common throughout the state. Results indicated that use of non-chemical options to control flies are commonly used by Washington dairy producers and may have become more widespread since the late 1990s. Extension professionals could improve outreach education to dairies by partnering with farm supply stores, veterinarians, and feed distributors.

4.
Environ Entomol ; 43(1): 116-22, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24472203

RESUMO

We tested an immunomarking system that used egg white as marker and enzyme-linked immunosorbent assay as a detection assay to characterize face fly (Musca autumnalis DeGeer) dispersal from cow pats in a pastured beef cattle operation. In microcage assays, adult flies acquired marker after contact with cow pats that were treated with marker and field aged up to 11 d. In arena assays on sprayed full-size cow pats, 77% of eclosed face flies acquired the marker. In a field-marking study, four applications of egg white marker were applied on freshly deposited cow pats over a summer at two peripheral paddocks to a main grazing pasture of ≍50 head of beef cattle. Of the 663 face flies captured, 108 were positive for the egg white marker (16.3%). Of the marked flies, ≍ twofold more male than female flies were captured. Sex-specific dispersal distances were roughly equal up to 450 m, with 11% of female flies dispersing >450 m. Dispersal capability of face flies is discussed in relation to efficacy of rotational grazing and other IPM strategies.


Assuntos
Distribuição Animal , Muscidae , Animais , Bovinos , Clara de Ovo , Ensaio de Imunoadsorção Enzimática , Fezes , Feminino , Masculino
5.
Pest Manag Sci ; 70(1): 123-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23512609

RESUMO

BACKGROUND: Face flies, Musca autumnalis De Geer (Diptera: Muscidae), and houseflies, Musca domestica L. (Diptera: Muscidae), have a significant impact on livestock and dairy production throughout North America. Pyrethroid insecticide efficacy can be affected by exposure to direct sunlight, and the rate of photodegradation is substrate and formulation dependent. Insecticide-treated netting (ITN) is finding new applications in crop and livestock production systems. A baseline study using long-duration no-choice assays has been carried out to gauge the effectiveness of ITN treated with ß-cyfluthrin, λ-cyhalothrin and bifenthrin on face flies and houseflies. RESULTS: After 12 weeks in direct sunlight, ITN treated with ß-cyfluthrin was still highly insecticidal to face flies and houseflies, producing 100% mortality in petri dish assays. However, sunlight reduced the insecticidal activity of λ-cyhalothrin, with 3% of face flies and 50% of houseflies surviving after exposure to ITN that had been deployed for 10 weeks. Insecticidal activity was greatly reduced on bifenthrin-treated netting, with 20% of face flies and 50% of houseflies surviving in assays with netting deployed for only 3 weeks. CONCLUSION: With careful choice of the pyrethroid applied, treated netting could be an important component of livestock integrated pest management programs focused on sustainable practices.


Assuntos
Moscas Domésticas/efeitos dos fármacos , Controle de Insetos/instrumentação , Controle de Insetos/métodos , Inseticidas/farmacologia , Muscidae/efeitos dos fármacos , Nitrilas/farmacologia , Piretrinas/farmacologia , Animais , Luz Solar
6.
Transgenic Res ; 20(1): 201-14, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20386982

RESUMO

Genetic transformation of the codling moth, Cydia pomonella, was accomplished through embryo microinjection with a plasmid-based piggyBac vector containing the enhanced green fluorescent protein (EGFP) gene. Sequencing of the flanking regions around the inserted construct resulted in identification of insect genomic sequences, not plasmid sequences, thus providing evidence that the piggyBac EGFP cassette had integrated into the codling moth genome. EGFP-positive moths were confirmed in the 28th and earlier generations post injection through PCR and Southern blot analyses, indicating heritability of the transgene.


Assuntos
Baculoviridae/genética , Elementos de DNA Transponíveis/genética , Vetores Genéticos/genética , Proteínas de Fluorescência Verde/genética , Mariposas/genética , Transformação Genética , Animais , Embrião não Mamífero , Proteínas de Fluorescência Verde/metabolismo , Microinjeções , Mariposas/metabolismo , Plasmídeos/genética , Transgenes
7.
J Food Sci ; 75(1): S68-73, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20492204

RESUMO

UNLABELLED: The presence of Multicolored Asian Lady Beetles (MALB) in grape juice is increasingly problematic. The overall objective of this study was to determine the specific sensory impacts of MALB on Concord and Niagara grape juice. The aroma threshold for MALB-taint in both juices was determined and expressed as the best estimate threshold (BET). The aroma BET for MALB-taint in Concord grape juice was 1.8 and 0.65 MALB/L Niagara grape juice. The specific sensory attributes of the grape juices influenced by the presence of MALB were then described. In Concord grape juice, trained panelists (n = 9) found significant increases in vegetal aroma and earthy flavor as MALB concentration increased from 0.45 to 7.2 MALB/L. In Niagara grape juice, with increasing MALB concentration, trained panelists (n = 8) indicated significant decreases in honey and sweetness with corresponding increases in sourness, astringency, and vegetal and earthy aromas and flavors (P < 0.05). For both aroma and flavor, consumer rejection studies were performed using paired preference comparisons of control juice to MALB-tainted grape juice. For Concord grape juice, consumers (n = 60) rejected the aroma of MALB-tainted juice at 1.8 MALB/L and the taste/flavor of the MALB-tainted juice at 3.6 MALB/L. For Niagara juice, consumers rejected the aroma of the juice at 3.6 MALB/L. This study demonstrated the presence of MALB negatively impacts the sensory properties of Concord and Niagara grape juice. Grape juice processors may use this research for quality control measures and for establishing tolerance limits. PRACTICAL APPLICATION: The Multicolored Asian Lady Beetle (MALB), initially used for biocontrol, has been shown in previous literature to impact the sensory properties of wines. The presence of MALB in grape juice is now becoming problematic; however, there is little research describing the specific sensory impacts of MALB on grape juice. This study examined the sensory impact of MALB on both Concord and Niagara grape juice. While the threshold and trained panel evaluations from this study provide valuable sensory profile information, grape juice processors may be particularly interested in the consumer rejection of MALB-tainted grape juice as they can use this research for quality control measures and for establishing tolerance limits.


Assuntos
Besouros/fisiologia , Vitis , Adolescente , Adulto , Idoso , Animais , Bebidas , Comportamento de Escolha , Mel , Humanos , Pessoa de Meia-Idade , Odorantes , Comportamento Predatório , Paladar , Estados Unidos
8.
J Insect Sci ; 8: 1-10, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-20298117

RESUMO

The presence of volunteer potato Solanum tuberosum L., cutleaf nightshade, S. triflorum N., and hairy nightshade, S. physalifolium Rusby (Solanales: Solanaceae), throughout potato crop rotations can diminish the effectiveness of crop rotations designed to control disease and pest problems associated with growing potatoes. In greenhouse bioassays, larvae of the Colorado potato beetle, Leptinotarsa decemlineata Say (Coleoptera: Chrysomelidae) were placed in population densities of 0, 5, 10, and 40 per potato (cv. Russet Burbank) plant and 0, 5, 10, and 15 per cutleaf nightshade and hairy nightshade plant. Plants were treated with different rates of herbicides including fluroxypyr, prometryn, and mesotrione rates, and the physiological response on the potato plants was assessed by weighing shoot biomass 14 days after treatment. Consistently, across all bioassays, rate response functions were shifted as L. decemlineata density increased, such that less herbicide was required to achieve control. For instance, the herbicide rate needed to achieve 90% reduction in potato biomass was reduced from 62 to 0 g fluroxypyr per hectare and 711 to 0 g prometryn per hectare as L. decemlineata density was increased to 40 larvae per plant. Herbivory at higher L. decemlineata population densities and herbicides above certain rates resulted in large reductions in cutleaf and hairy nightshade biomass. Differences in rate response functions among L. decemlineata population densities indicated that L. decemlineata contributed to weed suppression in combination with herbicides. These data suggest that integrated weed management systems targeting volunteer potato, cutleaf nightshade, and hairy nightshade can be more effective when herbicide applications are combined with herbivory by naturally occurring Colorado potato beetles.


Assuntos
Agricultura , Besouros/fisiologia , Herbicidas , Solanaceae , Análise de Variância , Animais , Bioensaio , Biomassa , Brotos de Planta/fisiologia , Densidade Demográfica
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