Corn cob dry

Statistical Analysis

Nine treatments (experimental units) were formulated from the combination of three MC

levels (15, 25 and 35 % w.b.) and three temperatures (10, 20 and 30ºC), performed in triplicate

(three runs), corresponding to a 3x3 complete factorial design. Temperature treatments were

randomly allocated to a chamber and moisture treatments were randomly allocated to certain
39

order within each chamber. For every replication (run) there would be a chamber randomly

assigned to one of the three temperatures and successively randomized on the later runs.

Statistical Analysis System (SAS Institute Inc) was used to analyze the data, with ANOVA

(analysis of variance). Differences in means were determine using Tukey-Kramer method with

alpha ≤ 0.05.

Results and Discussion

Table 1 gives the amount of dry matter loss, as estimated by CO₂ evolution for each of

the treatments after 21 days of incubation. In general, treatments with 15% moisture content and

10ºC had nearly no dry matter loss (average of 0.1 percent), while higher moisture (35%

moisture content) and higher temperature (30ºC) had on average 2.75 % loss. Similar rates of

degradation were observed under 35% moisture and 20ºC averaging 2.4% DM loss.

Results drawn from the ANOVA indicates that temperature, moisture and the interaction

within both are highly significant (p values = 0.00032, <0.0001 and 0.0017 respectively),

whereas the replication was not significant.
40

Table 1: Average dry matter loss (%) for every combination between 15, 25 and 35%

moisture and 10, 20 and 30ºC.