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1.
Anatomy of the digestive tract and external body development during the embryonic stages of the caprine (Copra, bircus) The purpose of this work has been to establish the pattern of prenatal growth and normal development of the digestive tract and annex glands during goat embryonic stages. 21 embryos with ages ranging from 14 to 34 days (1.69 to 5.90 cm CR) as determined by registering the mating time, were obtained by cesarea. This material was histologically processed to obtain complete serial sections of the stomatodaeum, foregut, midgut, hindgut and cloaca. In this work, it is chronologically described the morphogenesis and histogenesis of the mouth, hypophysis, pharynx and its derivatives, stomach, intestine, liver, pancreas and cloaca. The results obtained establish chronological comparisons with the development of the lamb and gives information on the unitary origin of the gastric compartments in ruminants. 相似文献
2.
Amin A. Nomeir Nicolas P. Hajjar Ernest Hodgson Walter C. Dauterman 《Pesticide biochemistry and physiology》1980,13(2):112-120
EPN is twice as toxic as EPNO to house flies from both the Diazinon-resistant strain and the susceptible strain. EPN and EPNO are also eight times more toxic to the susceptible than the resistant strain. This is due to the ability of the resistant strain to metabolize these compounds to a greater extent. Metabolism by the glutathione S-transferases present in the 100,000g supernatant is more extensive than that by the NADPH-dependent microsomal mixed-function oxidases. The glutathione S-transferases are the major route of metabolism for EPN and appear to be the principal mechanism conferring resistance. EPN was metabolized by the microsomal fraction via oxidative desulfuration to the oxygen analog, EPNO, and by oxidative dearylation to p-nitrophenol. EPNO was metabolized by the same system to p-nitrophenol and desethyl EPNO as well as to an unknown metabolite. The soluble fraction metabolized EPN to p-nitrophenol, S-(p-nitrophenyl)glutathione, O-ethyl phenylphosphonothioic acid, and S-(O-ethyl phenylphosphonothionyl)glutathione. The identification of the latter conjugate demonstrates a new type of metabolite of organophosphorus compounds. EPNO was metabolized by the soluble fraction to p-nitrophenol and S-(p-nitrophenyl)glutathione. 相似文献
3.
Nicolas Rose Alain Abhervé-Guéguen Gérald Le Diguerher Eric Eveno Jean-Pierre Jolly Philippe Blanchard Aurélie Oger André Jestin François Madec 《Livestock Production Science》2005,95(3):177-186
The aim of this study was to determine the potential risk factors for PMWS at the individual pig level and assess the effect of the Pietrain paternal genetic background of the animals in a cohort study. The survey was set up in four PMWS-affected farms with 2 repetitions (batches) per farm. A representative sample of 60 pigs per batch, stratified according to the paternal genetic background (Pietrain: yes vs. no), was randomly selected after farrowing. The representative cohort was divided into 8 batches and the pigs were individually monitored from birth to slaughter. Survival analysis was used to determine the factors related to the time to PMWS. The litter-cluster effect was taken into account using the marginal Cox model (robust estimation of the covariance matrix) and the gamma shared frailty model which were compared.No protective effect of the Pietrain breed on the time to PMWS and the proportion of affected pigs in the offspring was found in this study. Piglets showing low circovirus type 2 (PCV2) titres at 7 weeks-old with no subsequent seroconversion and piglets from PCV2 negative sows were most likely to be affected by PMWS (HR=7.0 and 2.8, respectively). Active infection of the pregnant dams with parvovirus was related to an increased risk of PMWS in the offspring (HR=2.3). Neck injuries due to poorly performed injections in the dams were associated with an increased risk of PMWS with the marginal model (HR=2.1). Oxytocin injection (dams) during farrowing was protective against PMWS in the offspring (HR=0.6). 相似文献
4.
Talbot CE Mueller K Granger N Jeffery ND 《Journal of the American Veterinary Medical Association》2007,231(10):1558-1561
CASE DESCRIPTION: A 1-month-old female alpaca was examined because of progressive clinical signs consistent with an intracranial lesion. CLINICAL FINDINGS: Clinical signs included signs of depression, lethargy, tetraparesis, and neck weakness. Two large isointense intracranial masses could be seen on T1-weighted magnetic resonance images. On T2-weighted images, the masses contained concentric rings of hypointense and hyperintense material. TREATMENT AND OUTCOME: 2 abscesses were removed via a craniotomy that incorporated removal of the sagittal crest and surrounding skull and transection of the sagittal sinus. The bony deficit was replaced with polypropylene mesh. The alpaca recovered within 2 weeks and was fully integrated into the herd within 1 month after surgery. CLINICAL RELEVANCE: Findings indicated that surgical removal is a feasible means of successfully treating intracranial abscesses in juvenile alpacas. 相似文献
5.
Fabrizio Lisi Ramzi Mansour Carmelo Cavallaro Tuğcan Alınç Emanuele Porcu Michele Ricupero Lucia Zappalà Nicolas Desneux Antonio Biondi 《Pest management science》2023,79(12):5003-5014
Background
Although the pupal parasitoid Trichopria drosophilae is used in conservative and augmentative biocontrol of Drosophila suzukii infestations, current pest management strategies mostly rely on multiple insecticide applications. In this context, the aim of the study was to investigate the baseline toxicity of nine insecticides on D. suzukii larvae and their multiple sublethal effects (LC10) on immature stages of the pest feeding on contaminated diet and T. drosophilae developing within the intoxicated host.Results
Chlorpyriphos and azadirachtin showed the lowest and the highest LC10, the values of which were 9.78 × 1013 and 1.46 × 103 times lower than their recommended label field rate, respectively. Among tested insecticides, imidacloprid, malathion and dimethoate were the only treatments that did not affect the juvenile development time of D. suzukii, while spinosad and the organophosphates chlorpyriphos and dimethoate did not influence fly pupal size. No sublethal effects were recorded on T. drosophilae degree of infestation (DI) and juvenile development time. On the contrary, cyazypyr and dimethoate negatively affected the success of parasitism (SP) and the number of progeny of the pupal parasitoid, in association with malathion for the first parameter and spinosad for the fertility. Compared to the untreated control, more female progeny emerged following azadirachtin exposure, while dimethoate caused the opposite effect. Imidacloprid, lambda-cyhalothrin and spinetoram decreased hind tibia length of emerged parasitoids.Conclusion
This study provides new insights on the (eco)toxicological profile of nine insecticides and new information needed to support the deployment of T. drosophilae in the field within the sustainable management techniques against D. suzukii. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献6.
7.
The productivity and financial performance of dairy farms in New Zealand and Japan (Hokkaido) were analyzed. By recomposing the official statistics on the dairy industry relative to Japan, New Zealand has low milk yield productivity per cow, but higher per hectare performance because of their seasonal breeding and pasture grazing systems. In the revenue and expenses analysis, New Zealand had a high cash surplus ratio compared with Hokkaido. In the cost analysis, for expenses on a “per kg of raw milk” basis, New Zealand milk production costs are 29% of those in Hokkaido. More than 60% of the production costs were attributable to feed, interest charges and wages in New Zealand. In Hokkaido, the feed cost alone accounted for 73% of the total cost. There is also a remarkably high interest expenditure in New Zealand caused by non‐subsidized fund procurement from finance organizations. In the financial analysis, New Zealand dairy farms have only approximately 50% of the total assets per cow compared with farms in Hokkaido. But total liabilities per cow in Hokkaido are twofold to threefold greater than in New Zealand. The difference between total assets and total liabilities shows that Hokkaido dairy farmers have an equity that is 50–200% greater than New Zealand dairy farmers. In the management analysis, New Zealand has a low turnover ratio of gross assets caused by the seasonal breeding system. In conclusion, New Zealand has higher per hectare production performance than Hokkaido, but has a low utilization of gross assets caused by a seasonal breeding system based on pasture grazing. 相似文献
8.
A simulation model of the phenology of Cydia funebrana (plum fruit moth) is presented. The Logan function was used to determine the temperature‐dependent developmental rates of the eggs, larvae and pupae; a linear equation was used for the ageing rate of females. The mean fecundity of females as a function of age was expressed by a modified Bieri's function. In order to simulate the stochastic process, a time‐distributed delay model was used. Results from the validation of the model in northern Italy (1995 and 1997) are reported. Catches of male moths in pheromone traps and oviposition activity were monitored in orchards of mid‐ and late‐ripening plum cultivars. The model was then run using temperature data from each farm. When the oviposition activity forecast by the model was compared with that actually observed in the orchards, good correlations between actual and forecast oviposition were obtained. The model is already available for technicians in Emilia‐Romagna and is a valuable tool in integrated fruit production; it gives an indication of the right moment to apply insecticides or to carry out further monitoring activity to assess the risk of C. funebrana damage (e.g. by sampling actual oviposition on just a single occasion). 相似文献
9.
Marron N Dreyer E Boudouresque E Delay D Petit JM Delmotte FM Brignolas F 《Tree physiology》2003,23(18):1225-1235
Responses to successive drought and re-watering cycles (1-3 cycles) were compared in greenhouse-grown cuttings of Populus x canadensis (Moench) clones, 'Luisa_ Avanzo' and 'Dorskamp.' Total leaf number increment rate, duration of leaf expansion, total and individual leaf area expansion rates and stomatal conductance were recorded periodically during the experiment. Soil water content (SWC) and predawn leaf water potential (Psi(WP)) were measured four times during each drought cycle. In parallel, relative leaf water content (RWC) and specific leaf area (SLA) were estimated on leaves collected from the top to bottom of each cutting. Under well-watered conditions, 'Luisa_Avanzo' and 'Dorskamp' differed in their patterns of leaf area expansion. Although duration of leaf expansion was similar between clones, 'Luisa_ Avanzo' exhibited higher total leaf number increment rates and individual leaf area increases than 'Dorskamp.' As a result, 'Luisa_Avanzo' cuttings reached larger individual and total leaf areas than 'Dorskamp.' 'Dorskamp' leaves had lower SLA than 'Luisa_Avanzo' leaves. In response to successive drought cycles, both clones underwent decreases in total leaf number increment rates and in total leaf area expansion rates, but both whole-plant and individual leaf areas were drastically reduced only in 'Luisa_Avanzo.' 'Dorskamp' maintained a constant leaf area as a result of an increase in the duration of leaf expansion during drought and a significant stimulation of individual leaf area expansion rate and total leaf number increment rate in response to re-watering. Drought caused a greater decrease in SLA in 'Luisa_Avanzo' than in 'Dorskamp.' Expanded leaves of 'Dorskamp' were constitutively dense or thick, or both, whereas leaves of 'Luisa_Avanzo' became dense or thick, or both, only in response to drought. In both clones, re-watering caused partial recovery of SLA to control values. Our data confirm previous field and greenhouse observations that 'Dorskamp' is more tolerant to successive drought and re-watering cycles than 'Luisa_Avanzo.' We conclude that this difference is mainly attributable to the plasticity of 'Dorskamp' after re-watering, rather than to clonal differences in drought responses. 相似文献
10.
Mathieu Jonard Frédéric André François Jonard Nicolas Mouton Pierre Procès Quentin Ponette 《Annals of Forest Science》2007,64(2):141-150
Total Soil Respiration (TSR) was measured in pure and mixed stands of oak and beech and was partitioned into two contributions using the forest floor removal technique: Mineral Soil Respiration (MSR) and Forest Floor Respiration (FFR). In addition, laboratory incubations of the forest floor and the Ah horizon were performed to evaluate the heterotrophic respiration and the DOC production of these horizons. The relationships between soil temperature and the various soil respiration contributions in the three stands were compared using Q 10 functions. In situ, significant differences (α = 0,05) between stands were observed for the R 10 parameter (respiration rate at 10 °C) of the TSR, MSR and FFR contributions, while only the temperature sensitivity (Q 10) of TSR was significantly affected by stand composition. The effect of soil water content was only significant on MSR and followed different patterns according to stand composition. Under controlled conditions, the R 10 of the forest floor and of the Ah horizon varied with stand composition and the Q 10 of the forest floor decreased in the order: oak (2.27) > mixture (2.01) > beech (1.71). 相似文献