To determine the equivalent dose of xylazine in mg/kg for a 1,000 lb horse given 2 milliliters of a 100 mg/mL solution, we need to follow these steps:
1. Convert the weight of the horse from pounds to kilograms:
- We know that 1 pound (lb) is approximately equal to 0.453592 kilograms (kg).
- Therefore, the weight of the horse in kilograms is:
[tex]\[
1{,}000 \, \text{lb} \times 0.453592 \, \frac{\text{kg}}{\text{lb}} = 453.592 \, \text{kg}
\][/tex]
2. Calculate the total amount of xylazine administered in milligrams (mg):
- The concentration of xylazine is 100 mg/mL.
- The total volume administered is 2 mL.
- So, the total amount of xylazine given is:
[tex]\[
2 \, \text{mL} \times 100 \, \frac{\text{mg}}{\text{mL}} = 200 \, \text{mg}
\][/tex]
3. Determine the dose in mg/kg:
- We need to distribute the total amount of xylazine over the horse’s weight in kilograms.
- To find the dose in mg/kg:
[tex]\[
\frac{200 \, \text{mg}}{453.592 \, \text{kg}} \approx 0.440924884 \, \text{mg/kg}
\][/tex]
4. Select the closest equivalent dose from the given options:
- The calculated equivalent dose is approximately 0.440924884 mg/kg.
- Comparing this with the provided options, the closest value is:
[tex]\[
4) \, 0.44 \, \text{mg/kg}
\][/tex]
Therefore, the equivalent dose in mg/kg is [tex]\(0.44 \, \text{mg/kg}\)[/tex].
