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21.

Ovine and caprine stockbreeding have been gaining attention in developing countries as an attractive investment. On these animals, infectious diseases of the reproductive tract, such as leptospirosis, can compromise the production leading to economic losses. The present study aimed to determine the risk factors associated with incidental leptospirosis and its influence on the reproductive parameters of ewes and goats of Espírito Santo state, Brazil. A total of 737 animals distributed on 24 herds/flocks were studied, and an overall prevalence of 10.9 % seroreactive animals was observed. Serogroup Icterohaemorrhagiae was the most frequent in goats (97.0 %) as well as in ewes (78.3 %). Regarding risk factors related to leptospirosis, the presence of waterholes and the semi-intensive breeding system were the most important associated to seroreactivity. Besides, there was an observed association between seroreactivity and reproductive failures (P?<?0.05). Moreover, seroreactive ewes (relative risk (RR)?=?1.3) and goats (RR?=?1.9) presented more chances to have abortions than seronegative animals. Furthermore, seroreactive ewes presented 11.6 more chances of having premature births when compared to the seronegative ones. It can be concluded that Leptospira infection, mainly those caused incidental strains (such as Icterohaemorrhagiae serogroup), is a significant factor to reduce the productivity of small ruminants’ herds/flocks in the studied region, and environmental measures must be considered on control programs.

  相似文献   
22.

Background

Atopic dermatitis (AD) is the most common canine allergic skin disease and can significantly affect the quality of life of affected dogs. Treating canine AD with ciclosporin has been a subject of great interest in recent years. Many studies have provided substantial evidence of ciclosporin efficacy and safety in canine AD management, and for several years ciclosporin has been recognised as a major component of canine AD multimodal therapy. As a chronic condition, canine AD requires life-long medical management and treatment success relies in large part on product ease of administration. Two studies were conducted to assess the comparative voluntary acceptance and consumption of Cyclavance® (Virbac), a new oral liquid formulation of ciclosporin, and Atopica® (Novartis) either added to a small quantity of kibbles (study 1) or administered directly into the dog’s mouth (study 2).

Results

Over the course of the two studies 70 dogs assessed each of the ciclosporin formulations and 320 individual tests were performed for each tested product. Immediate prehension (in less than 2 seconds) occurred significantly more often with Cyclavance® (90.6% of the tests) than with Atopica® (14.4% of the tests) when products were mixed with 30 grams of dry food (p < 0.001). Moreover, Cyclavance® was significantly more often easily accepted than Atopica® (99.3% vs 27.1% of the tests, respectively) when products were administered directly into the dogs’ mouth (p < 0.0001). Cyclavance® was also more often totally consumed (98.3% of the tests) than Atopica® (2.2% of the tests) when mixed with a small amount of food (p < 0.001). However, both products were totally consumed once administered directly into the dogs’ mouth.

Conclusions

By facilitating cicloporin administration and consumption, Cyclavance® liquid formulation offers an interesting alternative to capsules that may improve dosing compliance and therefore the ability to benefit from the therapeutic effects in the long-term treatment of canine AD.  相似文献   
23.
The odor-active compounds of dry-fermented sausages with added nitrite or nitrate as curing agents were identified by gas chromatography-olfactometry (GC-O) applying the detection frequency (DF) method. The quantification of these compounds in the sausage was determined by multiple headspace solid-phase microextraction (multiple HS-SPME). There were no specific odor-active compounds related to the use of nitrite or nitrate although there were differences in the DF value of several compounds. The nitrite-added sausages presented higher DF values for ethanol, 1-hexanol, propanoic acid, 2-heptenal, and nonanal while the nitrate-added sausages had higher DF values for phenylacetaldehyde and 3-methyl-butanal. Eighteen compounds were quantified by multiple HS-SPME. Most of them were above their air detection thresholds, but only hexanal, heptanal, and 1-octen-3-ol were in a concentration higher than their oil threshold values. These compounds would probably be the main contributors to the aroma of fermented sausages.  相似文献   
24.
The time evolution of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH*) concentration in four solvents (methanol, ethanol, propanol, and acetonitrile) during its reduction by three flavanones containing an isolated p-catechol group (taxifolin, eriodyctiol, and fustin) as well as the time evolution of the mass spectra of the reaction mixture has been determined by spectrophotometry and liquid mass spectrometry, respectively. In alcoholic solvents the reduction curves consisted of an initial short but fast kinetics step followed by a longer slow kinetics step; in contrast, in acetonitrile the reduction curves completely lacked the slow kinetics step. From the results, a kinetic model for the reaction of reduction of the DPPH* by the isolated p-catechol group in flavanone type structures is proposed. According to this model, the p-catechol group rapidly transfers two hydrogen atoms to DPPH*, through a fast rate constant k1, yielding the corresponding o-quinone. Then, the intermediate o-quinone forms an adduct with the alcoholic solvent, through a slow rate constant k2, and regenerates the p-catechol group. The regenerated p-catechol group reduces additional DPPH* through a fast rate constant k3, yielding the corresponding o-quinone, which can form a new adduct with the solvent to regenerate the p-catechol group, and so on. From the kinetics model, two explicit kinetics equations have been derived that fit very well the experimental data points acquired from all assayed compounds in all of the experiments carried out, thus allowing an accurate determination of the corresponding rate and stoichiometric constants.  相似文献   
25.
The effect of four sterol biosynthesis-inhibiting fungicides added to the pitching wort on the evolution of several organoleptic parameters during the primary fermentation of young lager beer was assessed. Pyrimidine (nuarimol and fenarimol) and triazole (myclobutanil and propiconazole) fungicides were individually supplied to the pitching wort to obtain a concentration of 1 mg/L. A marked influence in the fermentation rate was observed for the samples with propiconazole residues. From the fourth day onward, the fermentation prematurely ceased (stuck fermentation), and therefore, statistical significant differences were found in fermented extract, alcohol content, fermentable carbohydrates, pH, color, and total polyphenol and flavonoid contents of beer. Myclobutanil residues are only influenced in the total polyphenol and flavonoid contents, while differences in the analyzed parameters were not noticeable for the samples containing nuarimol and fenarimol residues in comparison with the blank sample.  相似文献   
26.
27.
This study was conducted to determine the age and liveweight at puberty of 120 crossbred beef heifers submitted to four diets to achieve predetermined weight gains (kg/day): 0.5 (G500; n?=?32), 0.75 (G750; n?=?32), 1.0 (G1000; n?=?29), and 1.25 (G1250; n?=?27). Animals were classified depending on their level of crossing between Nelore (N) and Hereford (H): 25%N-75%H, 37.5%N-63.5%H, 43.7%N-56.7%H, 50%N-50%H, and 75%N-25%H. Reproductive evaluation was performed at the beginning and at the end of the experimental period by ultrasonography and hormone analysis. The average age and liveweight at puberty were 388.0?±?1.9 days and 331.4?±?1.3 kg, respectively. Animals from the 25%N-75%H group reached puberty earlier than heifers from other genetic groups supplemented with G1250 diet (P?<?0.05). Heifers with higher degree of Nelore (75%N-25%H) fed with G1000 diet showed estrus 42 days prior to mating, but only 57 % reached puberty at mating (P?<?0.05). Heifers with follicles of higher diameter reached puberty (P?<?0.05) earlier. Higher average daily weight gain showed a positive effect on follicular diameter and IGF-I level at puberty (P?<?0.01). Concentrations of GH were lower in heifers fed G1250 compared to G1000 diet (P?<?0.05). There was a significant interaction between nutritional level and insulin levels at puberty (P?<?0.01). We demonstrated the relationship between IGF-I and average daily gain on the onset of puberty in heifers. In conclusion, heifers submitted to the higher feeding level showed a higher follicular diameter and were younger at puberty.  相似文献   
28.
Ultrastructural morphological injuries and maturation rates were investigated in equine oocytes exposed to vitrification solutions (VS) containing synthetic ice blockers (SIBs) during different exposure times. In experiment 1, compact cumulus-oocyte complexes (COCs; n = 30) were randomly allocated to treatments: (1) fresh fixed (control); (2) VS-1 (1.4 M dimethyl sulfoxide [DMSO] + 1.8 M ethylene glycol [EG] + 1% SIB) for 3 minutes of equilibrium time and VS-2 (2.8 M DMSO + 3.6 M EG + 0.6 M sucrose + 1% SIB) for 1 minute (Eq-long); and (3) VS-1 for 1.5 minutes and VS-2 for 30 seconds (Eq-short). In experiment 2, compact (n = 248) and expanded (n = 264) COCs were evenly distributed to the following treatments: (1) immediate maturation in vitro (control); (2) vitrification using the Eq-short protocol as in experiment 1; and (3) vitrification using a stock solution containing 2.8 M formamide, 2.8 M DMSO, 2.7 M EG, 7% polyvinylpyrrolidone, and 1% SIB (Eq-short-mod). More (P < .02) oocytes with normal ultrastructural morphology were seen in fresh control and Eq-short groups than in Eq-long group. Metaphase-II (MII) rates were higher (P < .05) for oocytes with expanded cumulus than compact cumulus in the control group, and higher (P < .05) for oocytes with expanded cumulus than compact cumulus in Eq-short and Eq-short-mod groups. No difference in MII rates was detected among groups within each type of COC. In conclusion, reduction of exposure time to VS better preserved oocyte ultrastructural features, and MII rates were higher for vitrified oocytes with expanded cumulus. This study advances our knowledge on potential alternatives for vitrification of immature equine oocytes.  相似文献   
29.
Background: Tectono grandis (teak) is one of the most important tropical timber species occurring naturally in India. Appropriate growth models, based on advanced modeling techniques, are not available but are necessary for the successful management of teak stands in the country. Long-term forest planning requires mathematical models and the principles of Dynamical System Theory provide a solid foundation for these.
Methods: The state-space approach makes it possible to accommodate disturbances and avarying environment. In this paper, an attempt has been made to develop a dynamic growth model based on the limited data, consisting of three annual measurements, collected from 22 teak sample plots in Karnataka, Southern India.
Results: A biologically consistent whole-stand growth model has been presented which uses the state-space approach for modelling rates of change of three state-variables viz., dominant height, stems per hectare and stand basal area. Moreover, the model includes a stand volume equation as an output function to estimate this variable at any point in time. Transition functions were fitted separately and simultaneously. Moreover, a continuous autoregressive error structure is also included in the modelling process. For fitting volume equation, generalized method of moments was used to get efficient parameter estimates under heteroscedastic conditions.
Conclusions: A simple model containing few free parameters performed well and is particularly well suited to situations where available data is scarce.  相似文献   
30.
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