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1.
Using anatomical as well as radiographic and tomographic methods, sixty brains of the N. American mink were examined. It was found that the brain consists of four ventricles. Also, it was noted that the posterior horn was missing and that there was the olfactory recess present in the lateral ventricle, a large-size interthalamic connection present in the third ventricle, and a flat, necklace-like bottom in the fourth ventricle. Only recently, the ins and outs of the mink's anatomical structure have begun to absorb anatomists. Apparently, it is related to the fact that furry animals, among them the mink, are being domesticated as if "before our eyes". For this reason and because of the easy access to material, examining of the brain ventricles in the mink was taken up.  相似文献   
2.
Infrared thermography is a non-invasive technique which allows to distinguish between pregnant and non-pregnant animals. Detecting accurate body surface temperatures can be challenging due to external factors altering thermograph measurements. This study aimed to determine the associations between the ambient temperature, the hair coat features and the temperatures of mares' abdomens. It compared pregnant and non-pregnant mares throughout 11 months. The research was carried out on 40 Konik Polski mares, which were divided into pregnant and non-pregnant groups. The temperature (Tmax, maximal; Taver, average; Tmin, minimal) of the mares' abdomen was evaluated in two regions of interest: the whole area of the lateral surface of the mares' abdomen (Px1) and the flank area of the lateral surface of mares' abdomen (Px2). During the increasing period, the slopes in the linear regression equation did not differ significantly for ambient (Tamb) and surface temperatures in both groups. In the decreasing period, the slopes did not differ significantly for Tamb and Tmax in the non-pregnant group. They also did not differ for Tamb and Taver in Px1 and Tamb and Tmin in Px1 in both pregnant and non-pregnant groups respectively. Other slopes varied significantly (p < .001). There was no evidence of parallel changes in hair coat features and measured temperatures. The flank area appears more suitable for thermal imaging in pregnant mares due to the seasonal fluctuations in hair coat lengths.  相似文献   
3.
Gastrointestinal microbiota play a key role in the nutrients digestion and hence maintaining animal health and welfare. The diet offered to the animals in captivity may differ considerably from that on natural pastures. In a stabled maintenance system, horses have a limited choice of habitat and feed. Time spend for feeding is relevant for equine welfare because the reduction of the time devoted for foraging may be responsible for inducing gastric inflammation and ulceration. Therefore, in the present study, it was hypothesized that fecal bacterial fermentative processes differ between free-roaming and stabled Konik Polski Horses (KPHs) with respect to microbial enzymatic activity, and thus the fecal concentration of short-chain fatty acids (SCFA), which can be further utilized for assessing the feeding behavior and welfare in free-roaming versus stabled horses. The SCFA concentration and profile, as well as the extracellular and intracellular activities of selected bacterial enzymes, were characterized in horse feces collected during the winter and summer feeding seasons. The results showed higher enzymatic activity and SCFA production in the feces excreted by free-roaming versus stabled horses, especially during summer. An increase in pasture plant diversity may be beneficial for the gastrointestinal microbiota and hence for maintaining health and welfare.  相似文献   
4.
1. The aim of this study was to evaluate the occurrence of Campylobacter spp. in domestic and free-living pigeons and to evaluate the antibiotic resistance profiles.

2. The material consisted of cloacal swabs obtained from 108 homing pigeons and fresh faeces from 72 wild birds from Lublin and its vicinity. The identification of strains isolated on differential/selective media for Campylobacter spp. was carried out by MALDI-TOF and PCR. The susceptibility to antibiotics was evaluated by minimum inhibitory concentration (MIC) in Mueller-Hinton broth.

3. A total of 35 strains of Campylobacter spp. were isolated; 27 were identified as Campylobacter jejuni and 8 as Campylobacter coli. Over half of the isolates were resistant to erythromycin and streptomycin, 40% of strains were resistant to tetracycline and ampicillin and 37% isolates were resistant to amoxicillin. Resistance to two or more antibiotics was observed in all strains tested.

4. The results indicate that both domestic and free-living pigeons are reservoirs for bacteria of the genus Campylobacter, which are characterised by varied and growing resistance to commonly used antibiotics.  相似文献   

5.
Here organogenesis of tarda tulip (Tulipa tarda Stapf.) from callus explants is presented. The callus tissue was cultivated on MS media containing 3% or 6% sucrose and either no addition of BAP (6-benzyl-aminopurine) or supplemented with 0.5 μM BAP. The cultures were maintained under a 16?h photoperiod under white, red or blue fluorescent light, at 20?±?2°C for 12 weeks. This study aimed to determine the most suitable light conditions and medium composition for seed-derived callus explants in order to obtain an efficient formation of adventitious bulbs. There were no differences between the spectra of light in differentiating adventitious bulbs. Explants cultured in darkness (control), on 0.5?µM BAP and 3% sucrose, formed the highest number of adventitious bulbs. The efficiency of adventitious organogenesis amounted to 36.6 bulbs per 1?g of callus tissue. The fresh weight of biomass, cultured in these conditions, increased within 12 weeks from 1 to 6.99?g. Supplementation with BAP of the medium containing 3% sucrose promoted the formation of bulbs, but in the case of the medium with 6% sucrose, BAP had an adverse influence under every type of light. The obtained results provide a useful protocol for the micropropagation of T. tarda, which can be used commercially for rapid and cost-effective production of the tulip.  相似文献   
6.
The thalamic nuclei with their defined set of input-output connections are the primary channel for information flow to the cerebral cortex. Several data suggest that neurons of that area are involved in the response to various aversive stimulations. However the pattern of activation seems to depend on the stress model as well as the stage of maturation. In the present study we would like to check which nuclei of the thalamus show expression of c-fos in the response to the "open field test", and how this response pattern changes during the maturation process. 30 rats of age ranged from P0 to P120 (P-postnatal day) were studied. The experimental group was exposed to the "open field test" for 10 minutes. After perfusion and fixation, brains were cut and stained for c-fos with immunohistochemical method. Our results showed that during development the pattern of c-fos activity in the thalamic nuclei after stress stimulation undergoes significant changes. Distinct c-fos expression was observed in the paraventricular nucleus, intergeniculate leaflet and ventral lateral geniculate nucleus. These findings suggest that these nuclei may play a direct role in the stress reaction involved in the response to the "open field test".  相似文献   
7.
A distinguishing feature of the most common types of glaucoma is an increased intra‐ocular pressure (IOP), which has a damaging effect on optic nerve axons, leading to the progressive loss of retinal ganglion cells. Therefore, IOP‐lowering medications are the mainstay of glaucoma therapy. Topical prostaglandin F2α analogs (PGAs) are a relatively new class of ocular hypotensive drugs, which have made a huge impact on the treatment of glaucoma in dogs. This study summarizes the current state of knowledge on the mechanism of action of these agents and their effect on IOP in dogs and cats. It also discusses potential harmful side effects of PGAs and presents contemporary opinions about their role and place in the medical management of glaucoma in small animals.  相似文献   
8.
The objective of this study has been to determine the influence of food and ions on the pharmacokinetics of enrofloxacin (ENRO) in turkeys, administered per os at a dose of 10 mg/kg of body weight (b.w.). Co-administration of ENRO with ions or with food significantly retarded its absorption, and the interaction was more pronounced when the drug was given together with food. The bioavailability of ENRO was 65.78 ± 7.81% and 47.99 ± 9.48% with ions and food, respectively. The maximum concentration (Cmax) in plasma of animals exposed to ions reached 0.87 ± 0.26 μg/ml in a tmax of 2.07 ± 0.76 h; in animals which were fed while medicated, the analogous parameters were 0.36 ± 0.13 μg/ml and 8.06 ± 3.08 h. The PK/PD analysis demonstrated that a decrease in the concentration of ENRO in turkeys’ blood due to the interaction with ions or food might impair the drug's clinical efficacy toward some pathogenic microorganisms in turkeys if a routine dose of 10 mg ENRO/kg b.w. is administered.  相似文献   
9.
Echinacea purpurea (EP) and Echinacea angustifolia (EA) are ones of the most important world's herbs with immunotropic activity. They were traditional medicinal plants used by North American Indians for the treatment of various illnesses. Now they are cultivated in many countries and are used mainly to treat respiratory tract infections. Rhodiola rosea (RR) and Rhodiola quadrifida (RQ) are medicinal plants originated from Asia and used traditionally as adaptogens, antidepressants, and anti-inflammatory remedies. We previously reported, that extracts of underground parts of RR and RQ exhibited immunotropic activity. We have demonstrated in pigs that in vitro RR or RQ supplementation of blood lymphocyte cultures stimulated T cell proliferative response to Con A in lower, and inhibited it in higher Rhodiola extract concentrations. The aim of this work was to evaluate the in vivo effect of these herbal remedies on the in vitro proliferative response of mouse splenic lymphocytes to another T-cell mitogen- Phaseolus vulgaris haemagglutinin (PHA). We have found significant stimulation of proliferative response, in comparison to the controls, in mice fed lower doses of tested remedies, and inhibition, no effect or lower stimulation, in mice fed higher doses of these drugs.  相似文献   
10.
Obesity is the common nutritional disorder affecting more and more animals every year. Obese individuals have altered metabolism and disorders of many organs. Obesity may develop as a result of specific genetic, metabolic, nervous and environmental factors. Dietary management of obesity requires addressing the underlying metabolism of the animal, normalizing the glucose level and proper treatment of diabetes, which is usually associated with obesity. Novel nutrients like leptin, chromium, carnitine and starch added to the diet as well as new approaches in the obesity therapy are very important in successful weight management and treatment of this common disorder.  相似文献   
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