An evaluation of a controlled release system for selenium in lambs

Area of Science:

• Veterinary Science
• Animal Nutrition
• Trace Element Metabolism

Background:

• Selenium (Se) is a vital trace element crucial for animal health and immune function.
• Selenium deficiency can lead to significant health issues in livestock, impacting growth and productivity.
• Maintaining adequate Se status in lambs is essential for their development and disease resistance.

Purpose of the Study:

• To evaluate the efficacy of 100-day controlled-release anthelmintic capsules containing Se for lambs.
• To determine the impact of different Se dosages on blood Se concentrations over time.
• To assess the duration of Se supplementation provided by these controlled-release capsules.

Main Methods:

• Lambs were administered controlled-release capsules containing either 7.7 mg or 13.9 mg of Se.
• Blood Se concentrations were measured at baseline and at 100 and 210 days post-administration.
• Comparison was made between supplemented lambs and unsupplemented control lambs.

Main Results:

• Both 7.7 mg and 13.9 mg Se capsules significantly increased blood Se concentrations by day 100.
• The 13.9 mg Se dose resulted in higher mean blood Se levels (990 +/- 83.4 nmol/l) compared to the 7.7 mg dose (440 +/- 29.8 nmol/l).
• Blood Se concentrations declined by day 210 but remained elevated compared to controls, with the 13.9 mg dose offering sustained protection.

Conclusions:

• 100-day controlled-release anthelmintic capsules containing Se are effective in increasing and maintaining Se status in lambs.
• The 13.9 mg Se dosage provides effective protection against Se deficiency for at least 180 days.
• This delivery method offers a practical approach to managing Se supplementation in young ruminants.