1. Special Topics 504: Practical Methods in Analyzing Animal Science Experiments Factorial Designs Five different levels of probiotic treatments are tested on male and female trout in a 4 week feeding trial. H o : μ 2 1 = μ 2 2 = μ 2 3 = μ 2 4 = μ 2 5 Ha: Specific Growth Rates are not the same in all five diets. SexTrt1Trt2Trt3Trt4Trt5 Male28.239.646.341.056.3 Male33.240.842.144.154.1 Female36.437.943.546.459.4 Male34.637.148.840.262.7 Female29.143.643.738.660.0 Female31.042.440.136.357.3

2. Special Topics 504: Practical Methods in Analyzing Animal Science Experiments Latin Square Latin square designs (they are essentially Cayley tables) are used often in pond culture. A typical Latin square is a table of n x n filled with different treatments in such a way that each treatment occurs in only once in each row or column. 1 2 3 2 3 1 3 1 2 Entries are written as (r, c, t)

3. Special Topics 504: Practical Methods in Analyzing Animal Science Experiments Latin Square Latin squares are most often used in cross-over designs which are economical and used to examine both a test group and control group with the groups reversed after a period of time. T0 – T1 T1 – T2 TreatedControl Treated