The effects of bedding materials on learning and memory performance and texture preference in rats

Document Type : Original Articles


1 Faculty of Sciences, Shahid Bahonar University of Kerman

2 shahid bahonar university

3 Department of Biology, Faculty of Sciences, Shahid Bahonar University of Kerman, Kerman, Iran


The present study was designed to investigate the effect of different available bedding materials on learning and memory performance, bedding texture preference as well as intra-cage ammonia concentration in rats. The animals were housed on different bedding types for two weeks. Bedding materials were produced in the same sizes from poplar, walnut, pistachio, apricot, almond woods and alfalfa steam and live. Spatial and passive avoidance learning and memory were assessed by Morris water maze (MWM) and shuttle box tasks. A modifying six-arm radial maze was used to assess bedding texture preference by rats. For each bedding groups, average ammonia level (ppm) over a week was calculated. The data indicated that the rats that had walnut and almond chips show better learning and memory performance in both MWM and shuttle box tests than other groups. The weakest learning and memory performances were observed in rats exposed to alfalfa bedding. In texture preference test, the rats spent more time in walnut and almond arms, and less time in alfalfa. Besides, the total water and food intake as well as the number of visit to alfalfa arm were decreased as compared to other arms. Moreover, in alfalfa bedding cage, average intra-cage ammonia level was utmost. Overall, current bedding materials may contain diverse biochemically effective compounds or individual micro edges which alter learning and memory performances of rats.


Article Title [فارسی]

اثر مواد بسترساز بر عملکرد حافظه و یادگیری و ترجیح جنس در موش های صحرایی

Authors [فارسی]

  • مهدی عباس نژاد 1
  • راضیه کوشکی 2
  • سعید اسماعیلی ماهانی 3
  • عباس تاج آبادی 3
  • ریحانه نادری 3
1 بخش زیست شناسی ، دانشکده علوم ، دانشگاه شهید باهنر کرمان، کرمان، ایران
3 بخش زیست شناسی ، دانشکده علوم ، دانشگاه شهید باهنر کرمان، کرمان، ایران
Abstract [فارسی]

امروزه انواع مواد بستر ساز براساس درجه سلامت، در دسترس بودن و هزینه برای دام و حیوانات آزمایشگاهی مورد استفاده است. در مطالعه حاضر، عملکرد حافظه و یادگیری و ترجیح به مواد بستر ساز در موش های صحرایی نگهداری شده تحت مواد بستر ساز مختلف بررسی شد. حیوانات در مواد بستر ساز در اندازه مشابه از چوب خاک اره ، گردو، پسته، سمندر، بادام و ساقه و برگ یونجه برای دو هفته نگهداری شدند. حافظه و یادگیری با استفاده از تست ماز آبی موریس(MWM) و شاتل باکس بررسی شد. یک ماز شعاعی تغییر یافته برای سنجش ترجیح جنس مواد بسترساز استفاده شد. برای هر یک از مواد بسترساز سطح آمونیاک درون قفس طی یک هفته محاسبه و نتایج نشان داد حیواناتی که در چوب بادام و گردو نگهداری شدند توانایی حافظه و یادگیری بهتری در تست MWM و شاتل باکس دارند. ضعیف ترین حافظه و یادگیری در موش های صحرایی قرار گرفته در یونجه به عنوان ماده بستر ساز مشاهده شد. در تست ترجیح جنس، حیوانات زمان بیشتری را در بازوهای حاوی گردو و بادام و زمان کمتری را در ناحیه حاوی یونجه گذراندند. علاوه براین، مصرف آب و غذا و همچنین تعداد ورود به ناحیه حاوی ماده بستر ساز یونجه در مقایسه با دیگر مواد بستر ساز کاهش یافت. همچنین، در قفس حاوی یونجه بیشترین سطح آمونیاک مشاهده شد. در مجموع نتایج نشان داد، مواد بسترساز با جنس متفاوت و خواص شیمیایی معین اثرات متفاوتی بر عملکرد حافظه و یادگیری موش های صحرایی دارند.

Keywords [فارسی]

  • مواد بسترساز
  • حافظه و یادگیری
  • ترجیح جنس
  • موش صحرایی
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