<p style="text-align: justify;"><span id="result_box" lang="fr"><span class="hps atn">De grandes quantités d'</span>eau <span class="hps">et d'électrolytes</span> <span class="hps">sont échangées</span> <span class="hps">quotidiennement</span> <span class="hps">entre</span> <span class="hps">le contenu du</span> <span class="hps">tractus gastro-intestinal</span> <span class="hps">et</span> <span class="hps">le sang.</span> <span class="hps">La quantité d'eau</span> <span class="hps">sécrétée dans le</span> <span class="hps">tractus gastro-intestinal</span> <span class="hps">est de 15-20</span> <span class="hps">litres par</span> <span class="hps">100 kg de</span> <span class="hps">poids corporel</span> <span class="hps">par jour</span> <span class="hps">(tableau 9</span>) <span class="hps">.Ce</span> <span class="hps">fluide contient</span> <span class="hps">de fortes concentrations de</span> <span class="hps">sodium et de chlorure</span>, mais des mécanismes <span class="hps">efficaces d'absorption</span> <span class="hps alt-edited">dans</span> <span class="hps alt-edited">l'intestin grêle</span> <span class="hps alt-edited">et le gros intestin</span> <span class="hps alt-edited">ré-absorbent</span> <span class="hps">de manière efficace</span> <span class="hps alt-edited"> à la fois</span> <span class="hps">l'eau</span> <span class="hps">et les minéraux</span> <span class="hps">vers le sang</span>. <span class="hps">L'ingestion de</span> <span class="hps">1 kg de</span> <span class="hps">matière sèche comme</span> <span class="hps">du foin ou de</span> <span class="hps">la paille</span> <span class="hps">nécessite</span> <span class="hps">la sécrétion de</span> <span class="hps">12-14</span> <span class="hps">litres d'eau</span> <span class="hps">tandis que 1</span> <span class="hps">kg de concentré</span> <span class="hps">nécessite</span> <span class="hps">seulement 7</span> <span class="hps">litres</span>.</span><br /><span id="result_box" lang="fr"><br /> <strong><span class="hps">Flux</span> <span class="hps">de liquide</span> <span class="hps">et d'électrolytes</span> <span class="hps">dans l'intestin</span> <span class="hps">du cheval </span>:</strong></span><br /><br /></p>
<table style="width: 394px; height: 169px;" border="1" cellpadding="4" cellspacing="1">
<tbody>
<tr>
<td class="style1" valign="top" width="35%">
<p class="style3">Sécrétion</p>
</td>
<td class="style1" valign="top" width="65%">
<p class="style3" align="center">kg / 100 kg poids corporel / jour</p>
</td>
</tr>
<tr>
<td class="style1" valign="top" width="35%">
<p class="style3">Salive</p>
</td>
<td class="style1" valign="top" width="65%">
<p class="style3" align="center">3 - 4</p>
</td>
</tr>
<tr>
<td class="style1" valign="top" width="35%">
<p class="style3">Suc gastrique</p>
</td>
<td class="style1" valign="top" width="65%">
<p class="style3" align="center">1-2</p>
</td>
</tr>
<tr>
<td class="style1" valign="top" width="35%">
<p class="style3">Suc pancréatique</p>
</td>
<td class="style1" valign="top" width="65%">
<p class="style3" align="center">6 - 10</p>
</td>
</tr>
<tr>
<td class="style1" valign="top" width="35%">
<p class="style3">Bile</p>
</td>
<td class="style1" valign="top" width="65%">
<p class="style3" align="center">3</p>
</td>
</tr>
<tr>
<td class="style1" valign="top" width="35%">
<p class="style3">Sécrétions intestinales</p>
</td>
<td class="style1" valign="top" width="65%">
<p class="style3" align="center">2 - 4</p>
</td>
</tr>
<tr>
<td class="style1" valign="top" width="35%">
<p class="style3">Total</p>
</td>
<td class="style1" valign="top" width="65%">
<p class="style3" align="center">15 - 20</p>
</td>
</tr>
</tbody>
</table>
<p class="Bildtext"><strong><br /><span id="result_box" lang="fr"><span class="hps">Le débit quotidien</span> <span class="hps">de liquide</span> <span class="hps">et d'électrolytes</span> <span class="hps alt-edited">du grêle</span> <span class="hps">au gros intestin </span>:</span></strong></p>
<p class="Bildtext">&nbsp;</p>
<table style="width: 581px; height: 151px;" border="1" cellpadding="4" cellspacing="1">
<tbody>
<tr>
<td class="style1" valign="top" width="35%">
<p class="style3">Ration</p>
</td>
<td class="style1" valign="top" width="22%">
<p class="style3" align="center">Eau kg</p>
</td>
<td class="style1" valign="top" width="25%">
<p class="style3" align="center">Sodium g</p>
</td>
<td class="style1" valign="top" width="19%">
<p class="style3" align="center">Chlorure g</p>
</td>
</tr>
<tr>
<td class="style1" valign="top" width="35%">
<p class="style3">10 kg foin</p>
</td>
<td class="style1" valign="top" width="22%">
<p class="style3" align="center">110</p>
</td>
<td class="style1" valign="top" width="25%">
<p class="style3" align="center">360</p>
</td>
<td class="style1" valign="top" width="19%">
<p class="style3" align="center">190</p>
</td>
</tr>
<tr>
<td class="style1" valign="top" width="35%">
<p class="style3">5 kg foin + 3 kg concentré</p>
</td>
<td class="style1" valign="top" width="22%">
<p class="style3" align="center">75</p>
</td>
<td class="style1" valign="top" width="25%">
<p class="style3" align="center">250</p>
</td>
<td class="style1" valign="top" width="19%">
<p class="style3" align="center">130</p>
</td>
</tr>
<tr>
<td class="style1" valign="top" width="35%">
<p class="style3">4 kg paille + 5 kg concentré</p>
</td>
<td class="style1" valign="top" width="22%">
<p class="style3" align="center">85</p>
</td>
<td class="style1" valign="top" width="25%">
<p class="style3" align="center">280</p>
</td>
<td class="style1" valign="top" width="19%">
<p class="style3" align="center">145</p>
</td>
</tr>
</tbody>
</table>
<p style="text-align: justify;"><span id="result_box" lang="fr"><span class="hps">Dans le gros intestin</span> <span class="hps">70 à 90</span><span>% d'eau</span> <span class="hps">sécrétée</span> <span class="hps atn">est ré-</span><span class="alt-edited">absorbée</span><span>, en fonction de</span> <span class="hps">la vitesse de passage</span> <span class="hps alt-edited">du</span> <span class="hps">digesta</span> <span class="hps">intestinal</span> <span class="hps">et</span> <span class="hps">de la capacité des</span> <span class="hps">parties</span> <span class="hps">non digérés</span> <span class="hps alt-edited">des aliments</span> <span class="hps alt-edited">à se lier</span> <span class="hps">à l'eau.</span> <span class="hps">La</span> <span class="hps">perte la plus élevée</span> <span class="hps">en l'eau</span> <span class="hps">par des matières fécales</span> <span class="hps">se produit</span> <span class="hps">sur les régimes</span> <span class="hps">de</span> <span class="hps alt-edited">fourrages</span>. <span id="result_box" lang="fr"><span class="hps alt-edited">L'absorption</span></span> <span class="hps alt-edited">du sodium et du</span> <span class="hps alt-edited">chlorure</span> <span class="hps alt-edited">dans</span> <span class="hps">le caecum et le</span> <span class="hps">colon</span> <span class="hps alt-edited">fournit le</span> <span class="hps">potentiel osmotique</span> <span class="hps">pour faciliter</span> <span class="hps">la résorption</span> <span class="hps">de l'eau</span> <span class="hps">-</span> <span class="hps">osmose.</span> <span class="hps atn">Lorsque l'</span><span>apport alimentaire</span> <span class="hps">de sel</span> <span class="hps">est</span> <span class="hps alt-edited">marginal</span> <span class="hps">par rapport</span> <span class="hps alt-edited">aux besoins</span><span>,</span> <span class="hps">le cheval peut</span> <span class="hps alt-edited">absorber jusqu'à</span> <span class="hps">99</span><span>%</span> <span class="hps">de ces minéraux</span> <span class="hps alt-edited">des fèces</span><span>.</span> <span class="hps">Ce sont les</span> <span class="hps">reins,</span> <span class="hps alt-edited">et non pas l'intestin</span> <span>, qui régulent</span> <span class="hps">les</span> <span class="hps">réserves corporelles</span> <span class="hps">de minéraux</span> <span class="hps">tels que sodium</span><span>, potassium</span> <span class="hps">et chlorure</span><span>.</span></span><br /><br /><span id="result_box" lang="fr"><span class="hps">Le potassium</span> <span class="hps">est absorbé</span> <span class="hps">dans l'intestin grêle</span> <span class="hps atn">(</span><span>65-70</span><span>%)</span> <span class="hps">et</span> <span class="hps">peut être absorbé</span> <span class="hps">ou</span> <span class="hps alt-edited">sécrété</span> <span class="hps">dans</span> <span class="alt-edited">le gros intestin</span> <span class="hps alt-edited">en fonction du</span> <span class="hps alt-edited">statut</span> <span class="hps">minéral.</span></span></p>
<p style="text-align: justify;"><br /><span id="result_box" lang="fr"><span class="hps">Le calcium est absorbé</span> <span class="hps">dans</span> <span class="hps">la première partie de</span> <span class="hps">l'intestin grêle où</span> <span class="hps">le contenu</span> <span class="hps">de l'intestin</span> <span class="hps alt-edited">est acide</span>, <span class="hps">tandis que</span> <span class="hps">le phosphore</span> <span class="hps">est absorbé</span> <span class="hps">dans les parties</span> <span class="hps">intermédiaires et</span> <span class="hps">terminales de</span> <span class="hps">l'intestin grêle.</span> <span class="hps alt-edited">Les deux minéraux</span> <span class="hps">sont sécrétés dans</span> <span class="hps">le tube digestif</span> <span class="hps">par la salive</span> <span class="hps">et</span> <span class="hps alt-edited">les sucs gastriques et intestinaux</span><span>.</span> <span class="hps alt-edited">L'absorption</span> <span class="hps">est contrôlée <span id="result_box" lang="fr"><span class="hps alt-edited">de manière homéostatique</span></span></span><span>,</span> <span class="hps">et la vitamine</span> <span class="hps">D</span> <span class="hps">participe à</span> <span class="hps">la régulation</span> <span class="hps alt-edited">de l'absorption du calcium et du phosphore</span><span>.</span> <span class="hps">L'absorption de</span> <span class="hps">ces</span> <span class="hps atn alt-edited">minéraux depuis </span><span class="alt-edited">le gros intestin</span> <span class="hps">est négligeable</span>.</span></p>