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1.
断奶仔猪小肠结构和功能的变化及其影响因素   总被引:8,自引:1,他引:7  
断奶后仔猪随意采食量低下,生长速率减缓使养猪生产遭受巨大损失。断奶后仔猪肠绒毛萎缩,腺窝增生,这些消化道形态和功能的显著变化被认为是引起消化道消化吸收功能下降,最后造成断奶后生长受阻的根本原因。断奶引起仔猪消化功能下降最终导致生长受阻的报道很多,但确切原因还不清楚。本文就断奶引起仔猪消化道生理学、生物化学的变化及其影响因素进行论述,供深入研究参考。1断奶后小肠结构和功能1.1绒毛高度和腺窝深度断奶后绒毛萎缩,可由绒毛顶部细胞脱落增加或细胞更新速度减缓引起。断奶可导致绒毛细胞脱落增多而使绒毛变短,…  相似文献   

2.
断奶应激对仔猪肠黏膜形态的影响   总被引:3,自引:0,他引:3  
在仔猪断奶过渡期,胃肠结构受损是很普遍的,断奶后一段时间内,胃肠结构受损程度不同,本文研究了断奶后7d内(断奶后0-6d),仔猪小肠黏膜形态的变化,试验仔猪28日龄断奶。试验分7组,每组6头仔猪。从断奶当天开始,每1d定时定点剖杀取小肠前段,小肠中部,小肠后段作组织切片,观察其绒毛高度,隐窝深度。结果表明,断奶后前4d,绒毛高度缩短,隐窝加深,断奶后第4d绒毛高度最短,断奶后第5d开始恢复。  相似文献   

3.
断奶仔猪成活率低的原因与解决对策   总被引:1,自引:0,他引:1  
正断奶仔猪成活率是猪场关注的关键环节,分析断奶仔猪成活率低的原因及采取相应的对策从而不断提高断奶仔猪成活率,才能更好地提高猪场的经济效益,笔者经几年兽医临床仔猪管理经验总结出断奶仔猪成活率低的原因与对策,现介绍如下。1断奶仔猪成活率降低的原因1.1生理因素1.1.1断奶仔猪的小肠结构变化仔猪断奶后小肠出现严重的绒毛萎缩、隐窝变深,造成小肠吸收  相似文献   

4.
益生素不仅可维持仔猪肠道菌群平衡,还可有效抑制肠道病原菌,提高动物抗病力,提高仔猪的生产性能,从而提高猪农的经济效益.然而随着生猪养殖的集约化,保持早期断奶仔猪胃肠道的健康平衡是生猪养殖者的一大挑战. 1仔猪断奶后所引起的肠道健康问题 仔猪断奶后,突然离开母猪且日粮从母乳突然转换成固体饲料所造成的双重应激对仔猪胃肠道是极大的挑战.另外,断奶仔猪胃肠道酸系尚未发展完善,加上巨大的断奶应激和饲料形态的改变,导致小肠细胞的形态和结构发生了显著变化,小肠绒毛严重萎缩,隐窝深度明显增加,绒毛高度显著降低,这些变化使得肠道胰蛋白酶活性下降,肠道对营养物质的消化吸收率降低,机体免疫能力下降.  相似文献   

5.
在养猪生产中,常用日增重来衡量断奶仔猪的健康和生长性能,而影响断奶仔猪日增重的主要因素是断奶时所面临的大量应激(饲粮改变、母仔分离、环境变化等)。断奶应激会使仔猪肠道发生组织形态学和生理学上的变化,如肠绒毛萎缩、隐窝增生、肠黏膜通透性增强等,这些变化会引起仔猪消化和吸收功能下降或免疫机能降低,最终导致腹泻和生长性能下降。本文针对早期断奶应激引起的仔猪肠黏膜结构和屏障功能的变化作一简要综述,总结了一些可以作为评价肠黏膜结构和功能的一些标记物,并列举了饲粮中可用来缓解断奶应激损伤的一些饲料原料或添加剂,以期为仔猪生产和断奶应激的研究提供参考。  相似文献   

6.
羔羊不同断奶日龄对小肠黏膜形态的影响   总被引:2,自引:0,他引:2  
为了探索不同断奶日龄对羔羊小肠黏膜形态的影响,试验分别选取15、30和45日龄波尔山羊(♂)×南江黄羊(♀)杂交一代断奶羔羊各10只,分为3个试验组;同时选15日龄羔羊14只,自然断奶作为对照组。各试验组断奶后10 d(对照组分别在25、40和55日龄),空腹屠宰取十二指肠、空肠、回肠中部各2 cm作组织切片,观察其绒毛高度、隐窝深度和绒毛形态结构。结果表明:与对照组相比,各断奶组羔羊十二指肠、空肠和回肠的绒毛高度、隐窝深度和绒毛形态均有不同程度的变化。断奶日龄越早,羔羊小肠黏膜变化越明显,其中绒毛高度下降幅度越大,隐窝深度加深越严重,断奶10 d后恢复情况越差,断奶日龄推迟到30日龄时损伤较小,恢复较好。羔羊30日龄断奶饲喂代乳料,对其小肠形态结构影响较小,实施断奶最好。  相似文献   

7.
断奶日龄对仔猪肠粘膜形态的影响   总被引:33,自引:5,他引:28  
本文研究了不同断奶日龄对仔猪肠粘膜形态的影响。试验分17日龄(1组)、21日龄(2组)、28日龄(3组)、35日龄(4组)断奶4个处理组,每个处理3个重复,每个重复1窝,定时定点制杀取十二指肠、空肠上段、空肠下段、回肠作组织切片,观察其绒毛高度、隐窝 深度、绒毛宽度、肠壁厚度。结果表明,仔猪十二指肠、空肠上段、空肠下段和回肠的绒毛高度、隐窝深度、绒毛宽度、肠壁厚度均有不同程度的变化;断奶日龄越早,仔猪肠粘膜变化越大,其中绒毛高度下降幅度越大,恢复时间越长,一般在断奶后8-12d降至最低,随后恢复较快。1组仔猪十二指肠、空肠上段、回肠隐窝深度显著下降;绒毛宽度各组各部位均呈先变窄后变宽趋势,肠壁厚度以1组变化明显。从小肠各部位比较,绒毛高度十二指肠最高,空肠上段次之;隐窝深度、绒毛宽度也以十二指肠最深或最宽;肠壁厚度以回肠最厚。仔猪在29日龄时各组各部位肠粘膜指标降至最低水平,之后,随着日龄的增加,各指标增加显著。  相似文献   

8.
断奶仔猪又称保育猪,是指生后3~5周龄断奶到10周龄阶段的仔猪。 1 生理特点 胰脂肪酶、胰蛋白酶、胰淀粉酶、胰凝乳酶等活性下降。小肠出现严重的绒毛萎缩,隐窝变深,肠黏膜淋巴细胞增生和隐窝细胞有丝分裂速度加快。抗体水平降低,细胞免疫力抑制增强,血液免疫球蛋白的数量降低,免疫力和抗病能力低。  相似文献   

9.
本研究旨在探讨饲粮中添加酵母壁多糖对断奶仔猪生长性能和小肠黏膜形态结构的影响。试验采用单因素试验设计方法,选取180头遗传背景一致、健康状况良好、胎次和体重接近的21日龄断奶仔猪,随机分为4个组,每组5个重复,每个重复9头猪。4个组分别饲喂对照饲粮、0.15%酵母壁多糖饲粮、0.30%酵母壁多糖饲粮和0.45%酵母壁多糖饲粮。试验期21 d。结果表明:1)与对照组相比,饲粮中添加酵母壁多糖能够显著提高断奶仔猪平均日增重和平均日采食量(P0.05);酵母壁多糖有降低断奶仔猪腹泻率和料重比的趋势,但差异不显著(P0.05)。2)与对照组相比,饲粮中添加酵母壁多糖能够显著提高断奶仔猪空肠绒毛高度/隐窝深度值(P0.05),添加0.45%酵母壁多糖能够显著提高断奶仔猪空肠绒毛高度和十二指肠绒毛高度/隐窝深度值(P0.05)。由此可知,酵母壁多糖可提高断奶仔猪的生长性能,并改善小肠黏膜形态结构;综合生长性能、小肠黏膜形态及经济成本等指标,其在仔猪饲粮中的适宜添加量为0.30%。  相似文献   

10.
谷氨酰胺对早期断奶仔猪生长性能及肠道形态发育的影响   总被引:1,自引:0,他引:1  
选21日龄断奶的杜大长仔猪72头,按试验要求分为2组,每组3个重复,每重复12头。分别饲喂基础日粮和含1%谷氨酰胺(Gln)日粮,试验期21 d,在断奶后0 d、7 d和14 d分别屠宰取小肠测重,并取十二指肠、空肠、回肠测定绒毛高度和隐窝深度。试验结果表明:断奶后7 d,日粮中添加Gln可显著提高仔猪的平均日增重和小肠相对重量,提高十二指肠和空肠绒毛的高度,降低十二指肠和空肠的隐窝深度;断奶后14 d,日粮中添加Gln对断奶仔猪的生长和肠道形态发育影响与基础日粮组相比差异不显著。  相似文献   

11.
1 当前畜禽调运中存在的问题 1.1 调运户动物防疫意识不强 一是个别调运户未申领《动物防疫合格证》,没有动物防疫知识和相关法律法规知识.是违规调运的根源.  相似文献   

12.
The number of donkeys and mules throughout the world is stable, and awareness of their use and concern for welfare, pain recognition and treatment are receiving increasing veterinary interest. Therefore, accurate information about anaesthesia and analgesia in donkeys and mules is important to ever more equine practitioners. Since donkeys are physiologically and pharmacologically different from horses, knowledge on species specific aspects of anaesthesia and analgesia are very important. Mules combine elements from both donkey and horse backgrounds, leading to great diversity in size, temperament and body type. Physiologically, they seem to resemble horses more than donkeys. This review highlights the current knowledge on various anaesthetic and analgesic approaches in donkeys and mules. There is still much information that is not available about donkeys; in many circumstances, the clinician must use available equine information to treat the patient, while monitoring carefully to observe for differences in response to therapy compared to the horse.  相似文献   

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本文应用Fortana—Masson嗜银颗粒染色法研究了貉、蓝狐、银狐的胃及十二指肠内嗜银细胞的形态分布。结果表明:三种动物胃幽门腺中,嗜根细胞数量最多,呈锥状,嗜银颗粒较粗,密度大、染成深黑色。在胃底及胃贲门腺区、嗜银细胞数量少。在十二指肠部嗜银细胞呈蝌蚪形,嗜银颗粒细,呈黑褐色,密度较小。嗜银细胞的分布密度在三种动物中具有一定的差别。  相似文献   

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Fluxes of the anti-parasitic agents, [3H]-ivermectin, [3H]-selamectin and [3H]-moxidectin were studied across non-transfected and transfected canine kidney epithelial monolayers, MDCK II/wt, MDCK II-MDR1, MDCK II-MRP1 and MDCK II-MRP2. All four lines surprisingly expressed significant levels of P-glycoprotein (P-gp), coded for by MDR1, but MDCK II-MDR1 expressed increased levels compared to the other lines. MDCK II-MRP1 and MDCK II-MRP2 expressed increased levels of MRP1 and MRP2 respectively. Fluxes of [3H]-ivermectin, [3H]-selamectin, [3H]-moxidectin, and the P-gp substrates, rhodamine-123 and DiOC2, were polarized in the basolateral-to-apical (secretory) direction across the four lines. Selected MRP inhibitors used in relevant pharmacological concentrations did not block the secretory fluxes of either [3H]-ivermectin or [3H]-selamectin in either the non-transfected or MRP-transfected lines. In contrast, secretory fluxes of ivermectin and selamectin were inhibited in all four lines by the P-gp inhibitor, verapamil. These data confirm that ivermectin and selamectin are substrates for P-gp in four additional cell lines, but suggest that they are not significant substrates for MRP1 or MRP2 where there is background expression of P-gp. Since this pattern of expression also pertains on the blood-brain barrier, it is unlikely that MRP1 and MRP2 play a significant role in ivermectin and selamectin blood: brain distribution in vivo.  相似文献   

19.
Ventilation and gas exchange were studied in healthy, adult horses and cows, two large species with different lung structures and different breathing patterns. The oxygen uptake (VO2), carbon dioxide output (VCO2), respiratory rate (fR), minute ventilation (VE), alveolar ventilation (VA), alveolar oxygen pressure (PAO2), and VE/VO2 ratio were higher in the cows, while the tidal volume (VT) and physiological dead space (VD) were larger in the horses. The arterial blood gases, alveolar-arterial oxygen pressure difference (PAO2-PaO2) and VD/VT ratio did not differ between the two species. The higher VO2 in the cows was most likely due to the energy cost of standing, and possibly to a higher cost of digestion. The higher VE, VA, VE/VO2 and PAO2 were most likely secondary to the increased VO2 and the slightly higher respiratory exchange ratio (R) in the cows. In contrast to hypotheses based on allometric equations, the PAO2 of horses and cows did not appear to differ from that of smaller mammals. The VD was larger than that predicted from allometric equations, and even though the VD/VT ratio (0.50) was lower than the previously reported values for horses and cows, it was significantly larger than the predicted weight-independent value of 0.36. Re-examination of the data used to derive the equation for VD raised questions as to the validity of this equation, and it is suggested that caution be exercised in the use of allometric equations for prediction.  相似文献   

20.
针对越冬期东西方蜜蜂的过冷却点进行了测试并对其与越冬性能的关系进行了分析。结果发现:在越冬期,东西方蜜蜂存在过冷却点且二者差异显著,东方蜜蜂过冷却点明显低于西方蜜蜂,蜜蜂的过冷却点与其越冬性能密切相关。  相似文献   

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