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51.
Merle R Busse M Rechter G Meer U 《Berliner und Münchener tier?rztliche Wochenschrift》2012,125(1-2):52-59
In order to simplify the design of representative studies in animal populations the structural differences of animal husbandry (cattle, pigs and laying hens) in Germany were characterised. Several regions were defined and thus districts identified which are typical for the respective region and can be regarded as representatives for the whole region. Data on animal husbandry as well as human population per district originated from the Federal Statistical Office and were linked to the geometric data of the Federal Agency for Cartography and Geodesy. By this, data of "livestock units/square kilometre area" and "farms/square kilometre area" per district were calculated using methods of the spatial statistics Global Moran's Index, Anselin Local Moran's Index and Getis-Ord Gi*. With the help of these analyses six clusters could be identified which resulted in four large (Middle, Northwest, East, and South) and one smaller region (Northern Upper-Rhine) respecting the federal state borders. These regions differed significantly regarding animal and farm densities. The selection of typical districts was carried out with the help of the respective animal and farm data of the species pigs, dairy cattle and laying hens. The means of the selected districts (three to six per region) were within the 60%- and the 80%-percentile of at least two of the analysed variables. Concerning the region Northern Upper-Rhine no representative district was selected. This presented regionalisation including representative districts can be used for the design of scientific studies that are associated with animal husbandry in Germany. 相似文献
52.
Alejandro Mendoza Daniel Cavestany Gonzalo Roig Julio Ariztia Claudia Pereira Alejandro La Manna David A. Contreras Carlos S. Galina 《Livestock Science》2010,127(1):60-66
The effect of restricted suckling on milk yield and composition, udder health, and postpartum anoestrus in dairy cows in pasture-based systems, was studied in 32 Holstein multiparous cows and their calves. At calving, each cow–calf pair was randomly assigned to one of two treatments: restricted suckling (RS) of the cows by her own or another calf, twice daily for 30 min or artificial rearing (AR) of the calves with milk obtained from the bulk tank, offered twice a day in buckets. Treatments were applied until week 8 after calving. The diet of the cows consisted of direct grazing in improved pastures, corn silage and a commercial concentrate which was offered at milking. Milk production and composition, udder health, body condition score of the cows, body weight and milk intake of the calves were measured weekly, and the first postpartum ovulation was determined three times a week by ovarian ultrasonography. Cows with RS management had a lower machine-milked milk yield (17.9 vs. 24.8 kg/d), a lower fat percentage (3.21 vs. 4.11%) and 4% fat-corrected milk yield (16.2 vs. 25.7 kg/d), and also a lower average milk flow (1.35 vs. 1.76 kg/min) than cows in the AR treatment. There was no effect of treatment on milk protein percentage or udder health as measured by milk electrical conductivity. The interval from calving to first postpartum ovulation was shorter in the AR cows than in the RS cows (18.5 vs. 21.8 days). The RS calves consumed more milk (7.2 vs. 5.4 kg/d), gained more body weight (0.813 vs. 0.656 kg/d), and had a higher body weight at weaning (84.3 vs. 73.3 kg) than AR calves. Restricted suckling of grazing dairy cows had a negative effect on machine-milked milk yield, fat percentage and 4% fat-corrected milk yield, but had no effect on udder health or on improved weight gain and body weight at weaning of the calves. 相似文献
53.
The purpose of the study is to analyze the productivity and ecological functions of birch and oak stands growing under various anthropogenic influences. The objects of the study are birch and oak stands in permanent test plots of the Forest Experimental District of the Russian State Agrarian University—Moscow Timiryazev Agricultural Academy. It is revealed that oak stands are more productive than birch stands in the conditions of the city of Moscow. The contribution of both tree species to the formation of a positive oxygen balance of cities is approximately the same. Analysis of leaf surface index values shows that crowns of birch stands are capable of retaining more solids suspended in the air than oak stands. To maintain the ecological, aesthetic, sanitary-hygienic, and oxygen-producing functions of stands in the conditions of the city of Moscow, it is necessary to carry out economic measures aimed at the formation of mixed, uneven-aged coniferous- deciduous forests. 相似文献
54.
Elena N. Kashinskaya Evgeniy P. Simonov Galina I. Izvekova Aleksey N. Parshukov Karl B. Andree Mikhail M. Solovyev 《Journal of fish diseases》2020,43(1):23-38
Using the approach of sequencing the V3-V4 region of the 16S rRNA gene, we have analysed the bacterial diversity associated with the distinct compartments of the gastrointestinal tract of perch (Perca fluviatilis) and cestodes (Proteocephalus sp.) parasitizing their digestive tract. The dominant microbiota associated with cestodes (Proteocephalus sp.) was represented by bacteria from the genera Serratia, Pseudomonas and Mycoplasma. By comparing the associated microbiota of perch and cestodes, a clear difference in bacterial composition and diversity was revealed between the community from the stomach content and other parts of the gastrointestinal tract of fish. Microbiota associated with cestodes was not significantly different in comparison with microbiota of different subcompartments of perch (mucosa and content of intestine and pyloric caeca) (ADONIS, p > .05) excluding microbiota of stomach content (ADONIS, p ≤ .05). PICRUSt-based functional assessments of the microbial communities of perch and cestodes indicated that they mainly linked in terms of metabolism and environmental information processing and could play an important role in the nutrition and health of host. 相似文献
55.
Information on persistence ofBacillus thuringiensis (Bt) is needed to improve the microbial pest management programs against the pine processionary mothThaumetopoea wilkinsoni in pine forests in Israel. The persistence of the microbe under natural conditions of rain and sunlight was evaluated and
is documented here for the first time. Pine saplings were sprayed with three commercialBt products, Foray 48B, Delfin WG and Dipel DF, all used at 32,000 IU mg−1 in a formulation with 1% (w/v) of condensed milk. In experiments conducted in November and December of 2004, the saplings
were either exposed to rain and sunlight or were sheltered to avoid these environmental factors. The lowest rainfall recorded
in the 8-day experiments was 16.5 mm (test 2) and the heaviest was 71.1 mm (test 1). Solar irradiation ranged from 9.4 to
10.9 MJ m−2. The minimum temperature was close to 10°C and the maximum was less than 23°C. Needles of the treated saplings and their
controls were sampled after 0, 1, 5 and 8 days, and were fed to 1
st
or 2
nd
instar larvae. Dipel DF persisted better than Delfin WG and still retained its initial activity of 80–100% mortality on day
8 at low rainfall (test 2). Dripping ofBt from upper to lower branches was quantified with the larval bioassays. The milk formulation proved to be an effective rain-fasting
adjuvant.
http://www.phytoparasitica.org posting May 4, 2007. 相似文献
56.
57.
David A. Contreras Carlos S. Galina Peter Chenoweth 《Reproduction in domestic animals》2021,56(12):1479-1485
Small community cattle farmers in the tropics are facing challenges to deliver quality products whilst under pressure to increase milk and beef yields per cow. These challenges could be partially met by crossbreeding Bos taurus with Bos indicus (F1) cattle utilizing embryo transfer (ET) technology. The Bos taurus infusion would increase milk production, whilst the Bos indicus influence can improve resistance to the harsh environment of the tropics. Here, individuals from existing herds can be used to produce F1 embryos which benefit from hybrid vigour. Resultant female offspring would in turn receive an F1 embryo on reaching breeding maturity. This approach would help to provide a cost-effective, systematic approach to improve productivity in dairy and beef cattle in the tropics. However, full usage of ET, including in vitro applications, in the tropics will require improvements in procedures, resources and education. 相似文献
58.
Aly R Ravid U Abu-Nassar J Botnick I Lebedev G Gal S Ziadna H Achdari G Smirov E Meir A Ghanim M 《Pest management science》2011,67(12):1493-1498
BACKGROUND: Ecdysteroids are steroid hormones that control moulting and govern several changes during metamorphoses in arthropods. The discovery of the same molecules (phytoecdysteroids) in several plant species displayed a wide array of rather beneficial agricultural impact. Many representatives of the genus Ajuga plants contain phytoecdysteroids with a 5β‐7‐ene‐6‐one system exhibiting physiological activities in insects. RESULTS: By means of chromatographic (silica gel column, TLC) and LC‐MS, two major ecdysteroids (20‐hydroxyecdysone and cyasterone) have been isolated and identified from Israeli carpet bugle Ajuga iva (L.) Schreber (Lamiales: Lamiaceae) plants. Ajuga iva extract fractionated on the silica gel column yielded two fractions that showed high activity against the sweetpotato whitefly Bemisis tabaci and the persea mite Oligonychus perseae. A dose of 5 mg AI L?1 of the purely identified A. iva ecdysterone significantly reduced fecundity, fertility and survival of these pests, while commercial 20‐hydroxyecdysone at the same dose had lesser effects. CONCLUSION: The results demonstrate considerable efficacy of natural phytoecdysteroids against major agricultural pests, and suggests that these materials should be considered for potential development of friendly control agents. Copyright © 2011 Society of Chemical Industry 相似文献
59.
Flufenerim, a novel insecticide acting on diverse insect pests: biological mode of action and biochemical aspects 总被引:1,自引:0,他引:1
Ghanim M Lebedev G Kontsedalov S Ishaaya I 《Journal of agricultural and food chemistry》2011,59(7):2839-2844
A new chemical compound was tested for its insecticidal activity against several major insect pests. The compound, called "flufenerim", has a core pyrimidine structure and an unknown mode of action and showed potent activity against the sweet potato whitefly Bemisia tabaci (Gennadius), the green peach aphid Myzus persicae (Sulzer), and the African cotton leafworm Spodoptera littoralis (Boisduval); however, it did not show any activity against two thrips species: western flower thrips Frankliniella occidentalis (Pergande) and tobacco thrips Thrips tabaci (Lindeman). The compound was relatively potent against the three tested pests and caused mortality rates that reached up to 100% at concentrations under 10 mg of active ingredient (ai) L(-1). The action of the compound was very fast, and mortality was observed within 48 h after exposure of the insects to treated leaves. A unique characteristic of this compound is its very short residual activity, which approximates to 4 days after application under laboratory conditions and to 2 days under outdoor conditions for both B. tabaci and S. littoralis. Although this new compound's mode of action is yet unknown, its rapid and potent action against sap-sucking pests suggests that it acts on a very important target site in the insect body and possibly could be applied very close to harvesting. 相似文献
60.