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1.
Forestomach acidosis was diagnosed in 2 llamas and 4 alpacas. All were young, group-housed, sexually intact males. Clinical signs included forestomach atony, lethargy, ataxia, diarrhea, and tachycardia. Forestomach distention was observed in only 1 llama. Clinicopathologic abnormalities included low forestomach fluid pH, hyperchloremia, hypokalemia, and metabolic acidosis. Although camelids differ from domestic ruminants in typical management practices and behavioral, anatomic, and physiologic characteristics, they are, nonetheless, susceptible to forestomach acidosis. Gastric fluid analysis was essential for an accurate diagnosis. Four of 6 camelids recovered after PO and IV treatment with alkalinizing agents and fluids, antibiotics, and thiamine.  相似文献   

2.
Nutritional husbandry of captive wild ruminants often requires feeding these animals a supplemental diet to enhance their health, reproductive performance, and productivity. Although supplemental diets for wild ruminants are commercially available, few have been evaluated in controlled intake and digestion trials. Voluntary intake, digestive efficiency, nitrogen retention, and gross energy utilization of pronghorn (Antilocapra americana), mule deer (Odocoileus hemionus), mountain sheep (Ovis canadensis), mountain goats (Oreamnos americanus), and wapiti (Cervus elaphus) consuming a high-energy, high-protein pelleted supplement were compared. Voluntary intake of dry matter, energy, and nitrogen were similar (P > 0.34) between mountain goats and mountain sheep and consistently lower (P < 0.03) for these species than for pronghorn, mule deer, and wapiti. Differences in digestive efficiency among species were inversely related to dry matter intake rates. Apparent digestibility of dry matter, organic matter, and neutral-detergent fiber was 10-20% higher for mountain goats and mountain sheep than for the other species (P < 0.04). Although these findings suggest a superior digestive efficiency for mountain goats and mountain sheep, species comparisons are inconclusive because of the confounding effects of season and ambient temperature on voluntary intake and digestion. Under the conditions of this experiment, the diet tested was safe, nutritious, and highly palatable. Protein and energy concentrations appear to be sufficient to meet or exceed known nutritional requirements of captive wild ruminants.  相似文献   

3.
In this study we explored if the secondary bioenergetic failure, which occurs a few hours after recirculation, following transient middle cerebral artery occlusion (MCAO) in rats, is caused by a compromised reflow. We induced 2 hours of MCAO and measured CBF at the end of the ischemia, as well as 15 minutes, 1, 2, and 4 hours after the start of recirculation, using autoradiographic or tissue sampling 14C-iodoantipyrine techniques. After 2 hours of MCAO, the autoradiographically measured CBF in the ischemic core areas was reduced to 3 to 5% of contralateral values. The reduction in CBF was less in neighboring, penumbral areas. After recirculation, flow already normalized in core tissues after 15 minutes, and remained close to normal for the 4 hours recirculation period studied. However, in penumbral tissues, recovery CBF values were usually below normal. The results show that tissues that are heavily compromised by the 2-hour period of ischemia and are destined to incur infarction, show a "relative hyperemia" during recirculation. In fact, some areas of the previously densely ischemic tissue showed overt hyperperfusion. This finding raises the question whether the relative or absolute hyperemia reflects events that are pathogenetically important. Because drugs that clearly ameliorate the final damage incurred fail to alter the relative hyperperfusion of previously ischemic tissues, it is concluded that vascular events in the reperfusion period do not play a major role in causing the final damage.  相似文献   

4.
The specific motility patterns of the forestomach of ruminants, composed of three structurally distinct compartments (rumen, reticulum, omasum), require an elaborate intramural innervation. To demonstrate the complex structure of the enteric nervous system (ENS), whole mount preparations obtained from different sites of the bovine forestomach were submitted to immunohistochemical procedures in which neuronal (protein gene product 9.5, neurofilament 200) and glial (protein S-100, glial fibrillary acid protein) markers were applied. Immunohistochemistry performed on whole mounts allowed a detailed two-dimensional assessment of the architecture of the intramural nerve networks. Generally, the myenteric and submucosal plexus layers were composed of ganglia and interconnecting nerve fiber strands, whereas the mucosal plexus consisted of an aganglionated nerve network. However, the texture of the ENS showed considerable regional differences concerning the ganglionic size, shape and density and the arrangement of nerve fiber strands. The myenteric plexus of the ruminal wall, showing a low ganglionic density and wide polygonal meshes, contrasted with the nerve network within the ruminal pillar which consisted of ropeladder-like nerve fiber strands and parallel orientated ganglia. The highest ganglionic density was observed at the reticular groove, the most prominent ganglia were found within the omasal wall. Branches of the vagal nerve frequently ramified within the myenteric plexus layers. The submucosal plexus of the rumen was divided into an external and internal layer; the reticular submucosal plexus followed the cristae and cellulae reticuli, the omasal submucosal (sublaminar) plexus showed intra- and parafascicular ganglia apart from ganglia located at the junctions of the nerve network. The mucosal plexus of the rumen consisted of thin nerve fascicles ramifying between the ruminal papillae, and reticular mucosal nerve fibers passed throughout the base of the cellulae reticuli. The highly specialised nerve network of the intralaminar omasal plexus showed radial and transverse trajectories reflecting the spatial arrangement of the intralaminar musculature. The demonstrated structural complexity of the ENS reflects the functional complexity of the ruminant forestomach and indicates the relatively high degree of autonomy in coordinating the different motility patterns required for the processing of the ingesta.  相似文献   

5.
Curcumin (diferuloylmethane), the major yellow pigment in turmeric, has been shown to inhibit benzo[a]pyrene (BaP)-induced forestomach cancer in mice through mechanism(s) not fully understood. It is well known that while cytochrome P4501A1 (CYP1A1) and epoxide hydrolase (EH) are important in the conversion of BaP to its activated form, (+)-anti-7,8-dihydroxy-9,10-oxy-7,8,9,10-tetrahydrobenzo[a]pyrene [(+)-anti-BaPDE], the detoxification of (+)-anti-BaPDE is accomplished by glutathione (GSH) S-transferases (GST). Therefore, it seems reasonable to postulate that curcumin may exert anti-carcinogenic activity either by inhibiting activation of BaP or (and) by enhancing the detoxification of (+)-anti-BaPDE. Administration p.o. of 2% curcumin in the diet to female A/J mice for 14 days, which has been shown to cause a significant inhibition in BaP-induced forestomach tumorigenesis, resulted in a modest but statistically significant reduction in hepatic ethoxyresorufin O-deethylase (EROD) activity, a reaction preferentially catalyzed by CYP1A1. While EROD activity could not be detected in the forestomach of either control or treated mice, curcumin feeding caused a statistically significant increase (approximately 2.3-fold) in hepatic EH and GST activities. Hepatic and forestomach GSH levels, and forestomach EH and GST activities were not affected by curcumin treatment. Even though the levels of various hepatic GST isoenzymes were significantly increased upon curcumin feeding, maximum induction was noticed for the pi class isoenzyme (mGSTP1-1), which among murine hepatic GSTs is highly efficient in the detoxification of (+)-anti-BaPDE. In conclusion, the results of the present study suggest that curcumin may inhibit BaP-induced forestomach cancer in mice by affecting both activation as well as inactivation pathways of BaP metabolism in the liver.  相似文献   

6.
During 9 experimental and 93 clinical operations on the open heart under circulatory bypass the authors studied microclots of multicomponent perfusion mixtures. They observed an increased number of microclots after infusion of high-molecular plasma-substituting solutions and long-term intraapparatus recirculation. During the bypass there was an increased number of microclots in the "machine-patient" system. The complex of measures suggested by the authors contributes to a delay in additional formation of microclots during the perfusion and also reduces the number of posttransfusion complications.  相似文献   

7.
Forty-four species of Culicoides (Diptera: Ceratopogonidae) were caught in insect light traps during the first 2 years of studies on the epidemiology of bluetongue virus in the Caribbean and Central America. Traps were operated near sentinel ruminants which were bled monthly for serologic evaluation and then virus isolation. More than 570,000 individuals were identified. Culicoides insignis Lutz accounted for 90% of the catch, C. filarifer Hoffman/C. ocumarensis Ortiz 5%, C. furens Poey 3% and C. pusillus Lutz 2%. Other species accounted for less than 1% of the total catch. Sentinel ruminants became seropositive when C. insignis populations were high at many study sites. At a few sites C. pusillus and C. filarifer/C. ocumarensis were predominant or were present in large numbers during seroconversions of sentinels. Virus isolations were obtained from sentinel ruminants during times when these same species were present in large populations.  相似文献   

8.
We tested the hypothesis that dietary components reaching the bovine small intestine influence the expression of genes that encode the gastrointestinal neuropeptides cholecystokinin (CCK) and glucagon-like peptide-1 (GLP-1). The amount of digesta reaching the intestine was manipulated during the experiment by withholding feed from five heifers fitted with ruminal, duodenal, and ileal cannulas for 48 h and then subsequent refeeding. Duodenal and ileal biopsies were collected using a fiber-optic endoscope. A Northern hybridization procedure was used to evaluate changes in gene expression. Blood concentrations of CCK and GLP-1 were determined with RIA. The data indicate that CCK blood concentration and mRNA abundance decreased during the period of feed deprivation, but they returned to predeprivation values within 16 to 24 h of refeeding. The GLP-1 blood concentration also decreased during feed deprivation and returned to predeprivation values within 4 to 8 h of refeeding, despite the fact that proglucagon mRNA abundance did not change significantly during feed deprivation and refeeding. These findings provide evidence that CCK and GLP-1 are released in response to nutrients that reach the small intestine and may be involved in the physiological process of digestion and possibly play a role in regulating feed intake in ruminants.  相似文献   

9.
Dilution procedures using tritiated water and Evans blue dye (T 1824) were applied to estimate total body water and plasma volume in small ruminants, pigs and cockerels during the two different seasons in Zimbabwe. The amounts of total body water (TBW) obtained were between 60% to 85% of the body weight in sheep and goats, 40% to 60% in pigs and 63% to 75% in cockerels. TBW values were significantly higher (P < 0.05) in the small ruminants than in pigs and observed age differences were significant (P < 0.05) in the small ruminants. There were significant (P < 0.05) seasonal differences in the total body water mean values but nonsignificant (P > 0.05) differences in the plasma volume mean values for the domestic species investigated.  相似文献   

10.
The paper describes the energetic feed evaluation systems for ruminants, pigs, poultry and horses presently used in Germany. During the last ten years the "Ausschuss für Bedarfsnormen" (AfB; Committee of Nutrient Requirements) of the "Gesellschaft für Ern?hrungsphysiologie" (GfE, Society of Nutritional Physiology) introduced new recommendations for energy requirements of domestic animals including national and international references. The energetic requirements were factorially deduced (demand for maintenance and various performances) under consideration of partial efficiency of utilized metabolizable energy (ME) for various performances (k-values). Except for lactating cows (Net Energy Lactation; NEL) the energy requirements of other ruminants as well as of pigs and poultry are given in ME. At present, the energy requirement of horses is still expressed as digestible energy (DE). Besides several energy requirements reported there are equations to determine and to calculate the energy content of feeds (GfE, 1986-1998) and corresponding tables with include the nutritive values of feedstuffs for various species. The energy content of mixed feeds may be estimated by specific equations.  相似文献   

11.
The effects evoked by 5-hydroxytryptamine (5-HT; serotonin) on forestomach myoelectric activity were investigated in conscious sheep. Myoelectric signals were recorded with electrodes chronically implanted in the reticulum, rumen (dorsal sac) and omasal body, and were analysed by a computer-based method. The 5-HT receptors and the neuronal pathways involved in these actions were studied. The intravenous (i.v.) infusion of 5-HT (8 micrograms kg-1 min-1 for 5 min) evoked an inhibition of activity of the whole forestomach. Methiothepin, injected i.v. at 0.1 mg kg-1, inhibited rumen secondary contractions and omasum activity. However, forestomach activity remained unchanged after the administration of 0.2 mg kg-1 of ketanserin, ondansetron, tropisetron, GR-113808, phentolamine, propranolol, domperidone and naloxone. Atropine (0.2 mg kg-1), hexamethonium (2 mg kg-1) or haloperidol (0.1 mg kg-1) abolished rumen secondary cycles and inhibited omasum activity. In addition, atropine also suppressed primary cycles. GR-113808 blocked all 5-HT-induced effects. Furthermore, atropine or hexamethonium prevented the 5-HT-evoked inhibition of reticulorumen primary cycles. In contrast, the remaining antagonists did not alter the 5-HT-evoked forestomach hypomotility. In conclusion, 5-HT induces inhibition of forestomach myoelectric activity through 5-HT4 receptors, these actions being mediated by cholinergic neural pathways involving muscarinic and nicotinic receptors. However, adrenergic, dopaminergic or opiate pathways are not implicated.  相似文献   

12.
Two species of Echinochloa millets and their direct wild ancestor species were analyzed for proximate composition, and amino acid, calcium, and iron content. Additionally, lactate polyacrylamide gel electrophoresis (PAGE) was performed to separate and resolve prolamin polypeptide present in the wild and domesticated species. The protein, calcium, and iron content of the four species were comparable to or greater than in other major cereals. Calcium was higher in each of the wild species than their domesticated counterpart. Essential amino acid values for the three species analyzed were generally higher than the FAO/WHO standards, except for lysine. Densitometric analysis of lactate PAGE gels revealed that the domesticated species contained prolamin, polypeptides that were either absent or present in smaller amounts in the wild species. The results indicate a wide variation in the content of examined nutrients and suggest that there is opportunity for improvement in the nutritional value of the Echinochloa millets via selective crossbreeding of wild and domesticated species.  相似文献   

13.
14.
Polymorphism of the transferrin locus (Tf) was found in the laboratory rat and wild rats in Japan by polyacrylamide gel electrophoresis. Two phenotypes, "a" and "b," were distinguished in homozygotes. It is suggested that these are controlled by autosomal codominant alleles. In 10 laboratory strains, only the IS strain showed the a type. This allele found in the IS strain was broadly distributed in Japanese wild rats. It is considered to be derived from a wild rat in Japan. Linkage relationship between Tf and Alp-1 was not established.  相似文献   

15.
Four pilot-scale lysimeters were used to study the benefits of landfill operation with and without leachate recirculation in tropical weather conditions. Young and old landfills were simulated by filling lysimeters with a segregated fraction of fresh municipal solid waste (MSW) and MSW mined from an open dump site, respectively, and periodically monitoring leachate quantity and quality and biogas quality. For each substrate, one lysimeter was operated as a bioreactor with leachate recirculation and another lysimeter was operated as a controlled dump, for a period of 10 months. Densities between 652 and 825??kg/m3 could be achieved with fresh and mined MSW. Despite such compaction during waste placement, bioreactor technology helps in leachate management, especially in the case of the young landfill lysimeter operated in tropical weather. The benefits of leachate recirculation in the young landfill lysimeter were evident from the significant decrease in chemical oxygen demand (COD) (86%), biochemical oxygen demand (BOD) (82%), dissolved organic carbon (DOC) (85%), and volatile solids (75%) in leachates. However, ammonia nitrogen (amm-N) and chlorides in the leachates accumulated in bioreactor landfills. Operating an old landfill lysimeter as a bioreactor seemed to have no exceptional advantage in the context of leachate management, although leachate recirculation enhanced the methane potential of both fresh and mined MSW.  相似文献   

16.
From 1987 to 1993, a survey on the feeding behavior of Glossina fuscipes fuscipes was conducted in the Central African Republic. A total of 556 blood-meal samples was analyzed by ELISA. According to the results, the number of blood meals from cattle was rather low (12% on average). During the rainy season, this number increased significantly and varied according to the sampling area. Along the riverine forests, this amounted to 5%, while blood meals from wild ruminants amounted to 87%. In the neighborhood of watering-places, the number of cattle blood meals reached 9-22%. Reptiles were found to be important hosts (17-35%). In all cases, man presented a non-negligible host (4-14%), similar to suidae (2-19%). The authors discuss the relevance of these results to risk of trypanosomes transmission.  相似文献   

17.
There is evidence indicating that the carbapenem antibiotic panipenem decreases plasma concentrations of valproic acid (VPA) in epileptic patients during VPA therapy. The mechanism for panipenem-induced changes in the pharmacokinetics of VPA was investigated in rats with and without bile duct cannulation. The effect of panipenem on the pharmacokinetics of diclofenac, which undergoes extensive enterohepatic recirculation, was also examined. VPA (50 mg/kg of body weight) or diclofenac (10 mg/kg of body weight) was administered intravenously under the steady-state plasma panipenem concentration of 4 microgram/ml, which had been achieved by a constant infusion rate. Panipenem decreased the plasma VPA concentrations in rats without bile duct cannulation but did not change the volume of the initial space and protein binding of VPA. However, panipenem had no effect on the plasma VPA concentrations and the biliary excretion of VPA in rats with bile duct cannulation. The secondary increase in plasma diclofenac concentration observed in the absence of panipenem was diminished in the presence of panipenem. These findings suggest that panipenem decreases plasma VPA concentrations by suppressing its enterohepatic recirculation, probably due to a panipenem-induced decrease in the numbers of enteric bacteria.  相似文献   

18.
19.
Sequential changes of cerebral autoregulation were studied in 20 cats after recirculation of cerebral ischemia. The cerebral autoregulation was evaluated by autoregulation index (A.I.), calculating % delta cerebral blood flow (CBF)/delta cerebral perfusion pressure (CPP), with changing the mean arterial blood pressure (MABP) within 80-130 mmHg. Duration of ischemic insult was 15 min after disappearance of direct cortical response (DCR). Following recovery of cerebral circulation, MABP, CBF and intracranial pressure (ICP) were observed sequentially for at least 48 hours. In 6 of 20 cats the autoregulation was disturbed early after recirculation, and the ICP was increased, resulting in no cerebral blood flow (early deteriorated group). In the other 14 cats the autoregulation was restored immediately, but in 7 of the 14 cats it was disturbed again after 24 hours following recirculation (delayed deteriorated group), finally the ICP was elevated and the CBF became 0 as same as early deteriorated group. In another 7 cats it was not disturbed until 5 days. The changes in CBF following insult were five patterns. These were classified into type A (Gradual decrease), type B (Transient increase), type C (Constant maintenance), type D (Relatively rapid decrease) and type E (Rapid decrease). The delayed cerebral dysautoregulation occurred in the types except for type A and type E. These results suggested there was close relation between delayed dysautoregulation and delayed neuronal dysfunction that we reported previously. Moreover, we considered the delayed dysautoregulation could be speculated from the value of ICP/CBF immediately after recirculation and the pattern of the changes in CBF during ischemic insult.  相似文献   

20.
The measurement of dialysis access recirculation has important diagnostic implications. Recent recognition that its traditional means of measurement is fraught with the potential for substantially overestimating access recirculation requires that we alter current practice. Most of the potential error in the measurement can be overcome by using an arterial rather than a venous specimen for the "systemic" sample. For practical purposes, such a sample can be drawn from the dialysis afferent (arterial) line as long as it is done in a manner that minimizes both contamination by recirculated blood as well as the increase in blood urea nitrogen that occurs when the arteriovenous blood urea nitrogen gradient is dissipated by slowing or stopping dialysis.  相似文献   

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