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991.
Application of new procedures in the sphere of the control of sexual functions requires an extension of present knowledge of postparturient endocrinium or endogenic factors comprised in postparturient physiology of sexual activity. According to recent data, oxytocin, besides its uterotonic and luteolytic activity, acts as an ovarian factor in the local intrafollicular regulation of stereidogenesis and as a modulator of uterine secretion of prostaglandines. Based on present knowledge of oxytocin effects, this study was aimed at investigation of the influence of repeated carbetocin (Depotocin inj. Spofa) administration on the dynamics of changes in thyroxine (T4), triiodothyronine (T3), 17 beta-estradiol (E2), progesterone (P4) concentrations and their mutual correlations from the 36th hour till the 51st day after parturition. Simultaneous study of a possible delayed influence of applied carbetocin on conception of ewes after oestrus evocation on day 51 after lambing was carried out. Nineteen ewes of the Slovak Merino breed, lambed in the first decade of February, were assigned to the experimental (n = 9) and to the control group (n = 10). Experimental ewes were subjected to repeated postparturient carbetocin treatment at the dose 0.07 mg per animal. The first dose was applied i. m. in 24 hours, and the second in 72 hours after parturition. On day 51 oestrus was induced in nine ewes of each group by combined treatment with chlorsuperlutin (Agelin, vaginal pessaries, Spofa) and PMSG (500 I.U./animal). On the day of PMSG application ewes were housed together with rams for the period of the next six days. Samples of blood were taken 24 hours before parturition (-1st day), up to 36 h after parturition and on days 4, 7, 14, 17, 21, 25, 34, 42 and 51 after parturition. Concentrations of T4, T3, E2 and P4 were determined by commercial kits RIA-test-T4; RIA-test-T3; RIA-test-ESTRA and RIA-test-PROG (URVJT Kosice). Animal of the control group showed variations of T4 concentrations (Tab. I, Fig. 1) at the level of original values (59.4 +/- 9.69 nmol.l-1) up to the 21st day with the exception of temporary drop on day 4 and rise on day 7, insignificant compared to the -1st day. T4 concentrations of the control group displayed an intermittent increasing trend with the statistically insignificant peak after 36 h and on day 17, compared to the -1st day. After the 21st day controls revealed a sustained moderate increase while the experimental ewes displayed a decline of its concentrations until the 51st day.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
992.
稀释液渗透压对绵羊精液冷冻效果的影响   总被引:3,自引:0,他引:3  
本试验对绵羊冻精采用两次稀释时,从调整Ⅱ液中葡萄糖含量和降低甘油浓度两方面,改变稀释液的渗透压,测定冻精效果。先增减糖的比例,配制9-2(对照), 84-1和84-2等试验组,其稀释Ⅱ液渗透压1191,1026、1499mmol/kg,获冻精情期产羔母羊率61.69, 63.31, 54.55(P<0.05)。随后, 以84-1为对照,降低甘油浓度,设3个试验组,即87-2,88-1和88-1a,渗透压相应为747,456,463mmol/kg,冻精情期受胎率1987年84-1,87-2为65.37,67.37;1988年87-2,88-1,88-1a为63.16,62.50,46.55(P<0.05)。试验说明,绵羊冻精采取2次稀释法,第Ⅱ液以4%甘油,渗透压为747mmol/kg时,冻精效果最佳。  相似文献   
993.
Tumour necrosis factor (TNF), a polypeptide produced by mononuclear phagocytes, has been implicated as an important mediator of inflammatory processes and of clinical manifestations in acute infectious diseases. To study further the potential role of TNF in infectious diseases, recombinant Escherichia coli (E. coli) derived human (r.HuTNF-alpha) and bovine TNF (r.BoTNF-alpha) were intravenously (i.v.) administered in dwarf goats. Rectal temperature, heart rate, rumen motility, plasma zinc and iron concentrations, and certain other blood biochemical and haematological values were studied and compared with the changes seen after E. coli endotoxin (LPS) was administered (dose: 0.1 microgram/kg i.v.). Following a single injection of 4 micrograms/kg of r.BoTNF-alpha, shivering and biphasic febrile response were observed, accompanied by tachycardia, inhibition of rumen contractions, drop in plasma zinc and iron concentrations, lymphopenia, and neutropenia followed by neutrophilia. The i.v. administration of a single injection of 4 micrograms/kg r.HuTNF-alpha induced shivering and biphasic febrile responses, accompanied by anorexia and a similar drop in plasma trace metal concentrations when compared with r.BoTNF-alpha-treated goats. The TNF-alpha-induced symptoms were essentially the same as those that occurred after LPS administration. However, the time of onset of these changes after the injection of TNF-alpha was significantly shorter than after LPS. Moreover, the r.BoTNF-alpha induced a longer lasting neutrophilic leucopenia, less neutrophilia, and a more persistent lymphopenia than after LPS injection. Neither r.BoTNF-alpha nor LPS caused severe haemo-concentration. Furthermore, no cross-tolerance between r.BoTNF-alpha and LPS could be demonstrated. We conclude that both r.BoTNF-alpha and r.HuTNF-alpha induce many of the physiologic, haematologic and metabolic changes that characterize the acute phase response to LPS. The overlapping biological activities of r.BoTNF-alpha, r.HuTNF-alpha and LPS in dwarf goats may indicate that both recombinant tumour necrosis factors have some homology with caprine TNF-alpha.  相似文献   
994.
995.
Bei 72 einzeln gehaltenen Legehennen wurde die Fähigkeit zur selektiven Lysinaufnahme überprüft. 2 unterschiedliche Alleinfutter auf der Basis von Federmehl (A) oder Maiskleber (B), aber mit dem gleichen defizitären Lysingehalt (0,36%), wurden während einer zweiwöchigen Lernphase jeweils an eine Hälfte der Tiere verfuttert. Anschließend wurden beide Vorbehandlungen in je 4 Gruppen geteilt, und eine der Mangelrationen und eine mit Lysin bedarfsgerecht supplementierte Ration (A+ bzw. B+, 0,64%) in folgenden Kombinationen zur Selbstauswahl über 14 Tage angeboten: A/A+, A/B+, B/A+ und B/B+. Über den prozentualen Rationsanteil am Gesamtfutterverzehr wurde die selektierte Lysinaufnahme ermittelt. Mit beiden Mangelrationen wurde eine Anorexie und in Folge eine Leistungsdepression ausgelöst, die jedoch bei B stärker ausgeprägt war. Die lysinangereicherte Ration wurde in fast allen Fällen innerhalb weniger Tage signifikant und stetig zunehmend bevorzugt, was für einen erlernten Lysinappetit bzw. -hunger spricht. Gleichzeitig wurde eine deutlichere Präferenz für die Federmehlration beobachtet, die bei Gruppe A/B+ nach B sogar zu einer Ablehnung der ergänzten Maiskleberration führte. Vertrautheit bzw. Neuartigkeit und sensorische Qualitäten einer Ration spielten neben den physiologischen Effekten eine bedeutende Rolle bei der Selbstauswahl. Die komplexen Wechselbeziehungen zwischen Futter, hedonistischen Komponenten und Erfahrung für die Entwicklung eines spezifischen Hungers wurden diskutiert.  相似文献   
996.
4-Aminopyridine (4-AP) is the only pesticide that can be legally used in the US to reduce bird damage in ripening grain fields. Birds that consume grain baits treated with 4-AP (‘Avitrol’ FC-99®) exhibit erratic behavior and emit vocalizations that presumably scare away the rest of the flock. Yet the behavior of 4-A Pintoxicated birds has not been documented, and we do not know how other birds react when observing these intoxicated birds or what these observers learn from their experience. Hence, we examined the behavior of 15 4-A Pintoxicated red-winged blackbirds (Agelaius phoeniceus (L.)) and found that initial signs of intoxication occurred 12.5 min after consumption of the bait, with death following 16.3 min later. During this 16-min intoxication period, birds gradually lost muscular control, making their movements and vocalizations weaker until hardly perceptible. Other captive red-winged blackbirds (‘observers’) gave more alarm calls while witnessing a 4-A P-intoxicated bird in one room of their cage (treatment period) than they did during the pre-treatment period. Immediately after the intoxicated bird died and was removed from the room, the observers' behaviour returned to pre-treatment levels. Broadcasting calls of an intoxicated bird or the placement of an untreated bird in one of the rooms had little effect on the observers' behavior. In another experiment, the placement of a 4-A Pintoxicated or untreated red-winged blackbird or the broadcast of calls of an intoxicated bird at a feed station did not affect the number of free-ranging conspecifics feeding, within sight of, or vocalizing at, these feeder stations. These results suggest that red-winged blackbirds learn little from witnessing a distressed conspecific.  相似文献   
997.
Two mature breeding stallions were evaluated because of specific ejaculatory dysfunction, and each was found to have aortic-iliac thrombosis occluding 60 to 70% of the aortic lumen. In each case, the stallion had strong libido, normal mounting, and vigorous initial thrusting. With continued exertion, thrusting became weak and dismount was awkward. Treatment aimed at maximizing sexual arousal before mounting and reducing hind limb pain and exertion during breeding allowed these stallions to continue breeding. A program of gradually increasing daily exercise also was associated with improved breeding performance during subsequent breeding seasons. In cases of specific ejaculatory dysfunction, aortic-iliac disease should be included among the differential diagnoses.  相似文献   
998.
Anthelmintic efficacy of moxidectin, an experimental antiparasitic macrocyclic lactone, was evaluated in a group of 15 calves harboring naturally acquired gastrointestinal nematodes. Three groups of 5 calves each served as untreated controls (group 1) or principals that were given moxidectin PO at the rate of 0.2 mg/kg (group 2) or 0.4 mg/kg (group 3) of body weight. Equal numbers of control and treated calves were necropsied for parasite recovery on days 10 (3 control and 3 of each treatment group) and 11 (2 control and 2 of each treatment group) after treatment. Efficacies at both doses were greater than 99.8 and 99.9% against active and inhibited larvae and adults of Ostertagia spp, respectively. The overall mean efficacy of each dose was greater than 99.9%.  相似文献   
999.
The number of neurons in the coeliacomesenteric ganglia and the myenteric and submucosal plexuses of the jejunum, ileum and small colon, and the pathological changes induced in them, were studied in various types of equine dysautonomia. In all forms of dysautonomia, severe and extensive neuron loss and damage occurred in the ileum. In acute and subacute dysautonomia, jejunal neuron loss and damage were severe, but in chronic cases significantly less loss or damage occurred. The damage followed the same pattern in the small colon but it was always less obvious than in the jejunum. The distribution of the damage was uniform within a segment of the intestine. In fatal cases of dysautonomia, the clinical severity and duration of illness seems, in most instances, to be related to the amount of neuronal disruption occurring in the jejunum. Severe disruption results in acute/subacute dysautonomia, while milder damage leads to the chronic form.No case of dysautonomia was encountered in which enteric neuron loss and damage occurred without significant neuronal disruption also occurring in the coeliacomesenteric ganglia.Ileal neuronal damage and loss are not invariably worse than that in the jejunum, and the possible reasons for this, together with the relationship between neuronal damage and possible causes of dysautonomia, are discussed.Abbreviations H&E haematoxylin and eosin Deceased. Formerly of the Moredun Research Institute, 408 Gilmerton Road, Edinburgh, EH17 7JH, UK  相似文献   
1000.
Three oat (Avena saliva L.) populations (i.e., lines of descent), high grain yield (HG), high protein content (HP), and high protein yield per se (HGP), each developed by three cycles of S, recurrent selection, were evaluated for the effect of selection for groat-protein yield upon other agronomic traits. Selections making up the HG line of descent had high protein yield primarily due to high grain yield, and those selected for HP had high protein yield due to both high protein content and high grain yield. Selection in HGP was on the basis of protein yield per se. Selection caused increases in bundle weight, harvest index, vegetative growth rate, and seed number in all lines of descent. Heading date, plant height, and seed weight were unaffected, whereas groat percentage and test weight were decreased in HP and HGP. Heritabilities were high for heading date, plant height, test weight, and seed weight, moderate for harvest index and bundle weight, and low for groat percentage. Genetic variability generally declined from CO to C3 for all traits. Groat-protein yield and amount of protein per groat increased in all lines of descent. In HG, the increase in groat weight was due primarily to increases in the nonprotein fraction, with groat-protein content actually decreasing. In HGP, groat weight increased due to increases in protein and nonprotein fractions, and groat protein content remained constant. In HP, groat weight and amount of nonprotein per groat decreased, thus increasing groat-protein content. Three cycles of recurrent selection resulted in oat lines with groat-protein yields significantly higher than the highest lines from CO. Utilization of index selection may be desirable to obtain populations of greater breeding value.  相似文献   
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