查看完整版本: 家兔的消化特性

家兔的消化特性

<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><B style="mso-bidi-font-weight: normal"><SPAN lang=EN-US style="FONT-SIZE: 15pt"><FONT face="Times New Roman">1.</FONT></SPAN></B><B style="mso-bidi-font-weight: normal"><SPAN style="FONT-SIZE: 15pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">消化器官特点</SPAN></B><B style="mso-bidi-font-weight: normal"><SPAN lang=EN-US style="FONT-SIZE: 15pt"><?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p></SPAN></B></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><B style="mso-bidi-font-weight: normal"><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">①口腔的特殊结构</SPAN></B><B style="mso-bidi-font-weight: normal"><SPAN lang=EN-US style="FONT-SIZE: 14pt"><o:p></o:p></SPAN></B></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 28pt; mso-char-indent-count: 2.0"><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">上唇中央有一裂缝，形成豁嘴，呈三瓣形，使门齿露在外面，便于采集地面上矮小的植物和啃咬树皮等，这是其他家畜所没有的。</SPAN><SPAN lang=EN-US style="FONT-SIZE: 14pt"><o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">特殊的双门齿，上颌有两对门齿，有别于啮齿动物的单门齿。但兔的大又门齿属于恒齿，具有鼠类的啮齿行为。</SPAN><SPAN lang=EN-US style="FONT-SIZE: 14pt"><o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">口腔内</SPAN><SPAN lang=EN-US style="FONT-SIZE: 14pt"><FONT face="Times New Roman">4</FONT></SPAN><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">对唾液腺，有大量的唾液进入口腔，进行初步消化。</SPAN><SPAN lang=EN-US style="FONT-SIZE: 14pt"><o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><B style="mso-bidi-font-weight: normal"><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">②极发达的盲肠</SPAN></B><B style="mso-bidi-font-weight: normal"><SPAN lang=EN-US style="FONT-SIZE: 14pt"><o:p></o:p></SPAN></B></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 28pt; mso-char-indent-count: 2.0"><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">在所以单胃草食动物中，兔的盲肠所占比例最大，其长度于体长相当，容积为消化道总容积的</SPAN><SPAN lang=EN-US style="FONT-SIZE: 14pt"><FONT face="Times New Roman">42%</FONT></SPAN><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">。就象一个天然发酵袋，繁殖大量的微生物和原虫，与反刍动物的第一个胃相似，尤其对粗纤维消化起重要作用。</SPAN><SPAN style="FONT-SIZE: 14pt"><FONT face="Times New Roman"> <SPAN lang=EN-US><o:p></o:p></SPAN></FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><B style="mso-bidi-font-weight: normal"><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">③圆形球囊组织</SPAN></B><B style="mso-bidi-font-weight: normal"><SPAN lang=EN-US style="FONT-SIZE: 14pt"><o:p></o:p></SPAN></B></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 28pt; mso-char-indent-count: 2.0"><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">在回肠和盲肠连接处，膨大、壁厚中空，肌肉组织发达，兔特有的圆小囊，主要功能是：分泌碱性溶液，中和微生物发酵产生的过量有机酸，起防护作用；机械压榨食物的作用；消化吸收终端产物的作用。</SPAN><SPAN lang=EN-US style="FONT-SIZE: 14pt"><FONT face="Times New Roman"><SPAN style="mso-spacerun: yes">&nbsp; </SPAN><o:p></o:p></FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><B style="mso-bidi-font-weight: normal"><SPAN lang=EN-US style="FONT-SIZE: 15pt"><FONT face="Times New Roman">2.</FONT></SPAN></B><B style="mso-bidi-font-weight: normal"><SPAN style="FONT-SIZE: 15pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">消化特点</SPAN></B><SPAN lang=EN-US style="FONT-SIZE: 14pt"><BR></SPAN><B style="mso-bidi-font-weight: normal"><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">①对粗纤维的消化</SPAN></B><SPAN lang=EN-US style="FONT-SIZE: 14pt"><o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 28pt; mso-char-indent-count: 2.0"><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">兔对粗纤维的消化率为</SPAN><SPAN lang=EN-US style="FONT-SIZE: 14pt"><FONT face="Times New Roman">74%</FONT></SPAN><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，一定含量的粗纤维，可以保持消化物的稠度，有助于形成硬粪，当饲料中粗纤维缺乏时（低于</SPAN><SPAN lang=EN-US style="FONT-SIZE: 14pt"><FONT face="Times New Roman">5%</FONT></SPAN><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">），胃内容物特别容易消化，减少了在胃肠道的滞留时间，通过消化道时间是正常时的</SPAN><SPAN lang=EN-US style="FONT-SIZE: 14pt"><FONT face="Times New Roman">2</FONT></SPAN><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">倍，吸收营养物质的时间不充分，消化率降低，引起消化紊乱，采食量下降，腹泻。当饲料中粗纤维含量过高时（高于</SPAN><SPAN lang=EN-US style="FONT-SIZE: 14pt"><FONT face="Times New Roman">25%</FONT></SPAN><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">），肯定可以吸收利用的营养成分没多少，直接影响肉兔的快速生长。兔日粮中粗纤维的正常含量为</SPAN><SPAN lang=EN-US style="FONT-SIZE: 14pt"><FONT face="Times New Roman">12-15%</FONT></SPAN><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">。</SPAN><SPAN style="FONT-SIZE: 14pt"><FONT face="Times New Roman"> <SPAN lang=EN-US><o:p></o:p></SPAN></FONT></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><B style="mso-bidi-font-weight: normal"><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">②对蛋白质的消化</SPAN></B><B style="mso-bidi-font-weight: normal"><SPAN lang=EN-US style="FONT-SIZE: 14pt"><FONT face="Times New Roman"> <o:p></o:p></FONT></SPAN></B></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 28pt; mso-char-indent-count: 2.0"><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">兔子对青饲料中的蛋白质有较高的消化率，尤其对粗饲料中的蛋白质有很强的利用能力。兔盲肠蛋白酶活性远远大于牛的。以苜蓿干草为例，消化率达</SPAN><SPAN lang=EN-US style="FONT-SIZE: 14pt"><FONT face="Times New Roman">73.7%</FONT></SPAN><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">。</SPAN><SPAN lang=EN-US style="FONT-SIZE: 14pt"><o:p></o:p></SPAN></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><B style="mso-bidi-font-weight: normal"><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">③较强的解毒能力：</SPAN></B><B style="mso-bidi-font-weight: normal"><SPAN lang=EN-US style="FONT-SIZE: 14pt"><o:p></o:p></SPAN></B></P>
<P class=MsoNormal style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 28pt; mso-char-indent-count: 2.0"><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">兔子对植物中有毒的生物碱有较强的抵抗力，如我国的泽漆等都能采食而不中毒，这与兔子的肝脏大有关系，兔子的肝脏占其体重的</SPAN><SPAN lang=EN-US style="FONT-SIZE: 14pt"><FONT face="Times New Roman">3%</FONT></SPAN><SPAN style="FONT-SIZE: 14pt; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">。</SPAN><SPAN style="FONT-SIZE: 14pt"><FONT face="Times New Roman"> <SPAN lang=EN-US><o:p></o:p></SPAN></FONT></SPAN></P>