## 3 Results  
Effect of Different Nuts' Oil on Food Consumption and Growth Indicators in Adjuvant-Induced Arthritis (AIA) Rat Model  
Figure 2A-E presents changes in TFC, food efficiency, initial and final body weight, as well as weight gain in all groups of rats. The animal model was validated by changes in the final body weights of rats during the induction of AIA as well as one month later. The difference in TFC was insignificant (\(p\) = 0.714) between the groups. The TFC (Figure 2A) in the control group, AIA group, AIA + walnut oil, AIA + and peanut oil, AIA + cashew nut oil, and hazelnut oil groups was 129.6 \(\pm\) 10.407 g, 131.2 \(\pm\) 11.077 g, 131.2 \(\pm\) 17.513 g, 127.6 \(\pm\) 10.237 g, 120.8 \(\pm\) 5.119 g, and 126.4 \(\pm\) 11.393 g, respectively. In addition to an increase in the FE (Figure 3B) of the oil groups, the increase in the AIA group (1.758 \(\pm\) 0.218%)  
was reported versus the control group (0.843 \(\pm\) 0.154 g). The highest oil groups in terms of nutritional efficiency were the cashew nut oil group (1.598 \(\pm\) 0.178%) followed by the AIA + hazelnut oil (1.407 \(\pm\) 0.273%), AIA +walnut oil (1.195 \(\pm\) 0.115%), and AIA + peanut oil (1.083 \(\pm\) 0.073%) groups. Figure 2: Changes in total food consumption (**A**), food efficiency (**B**), initial body weight (**C**), final body weight (**D**), and weight gain (**E**) in all groups of rats. Model: One-way analysis of variance (ANOVA) with a statistical significance assumed at \(p\)\(\leq\) 0.05 followed by [PERSON]’s HSD post hoc test for statistically significant \(p\)-value. Data are presented as mean \(\pm\) SD for \(n\) = 5 rats/groups. a: Significantly different from the control rats. b: Significantly different from the adjuvant-induced arthritis model rats (AIA). c: Significantly different from AIA + walnut oil. d: Significantly different from AIA + peanut oil. Most of the growth indicators in the AIA group significantly changed versus those in the control group, although the rate of diet consumption was very similar among all groups. Although insignificant (\(p\) = 0.977), differences have been observed in terms of initial weight (Figure 2C) between all groups, but the AIA rats exhibited a significant (\(p\) = 0.00) increase in their final body weight versus the control group and rats in the nut oil groups (Figure 2D). All diet oils, including walnut, peanut, hazelnut, and cashew, significantly reduced the final body weights relative to the AIA model rats (400 \(\pm\) 18.775 g). The maximum improvement in weight loss was seen among rats fed peanut and walnut oil. A significant (\(p\) = 0.00) increase in the weight gain of rats (Figure 3E) was observed in the AIA group (229 \(\pm\) 16.897 g), while the increase in weight was only 108.2 \(\pm\) 13.719 g in the control group. However, the body weight gain of rats in the AIA + peanut oil group (138 \(\pm\) 12.247 g) and in the AIA + walnut oil group (155.2 \(\pm\) 7.362 g) was significantly (\(p\) = 0.00) lesser than those in the AIA group. Similarly, the body weight gain in the AIA + hazelnut oil group (178.6 \(\pm\) 40.906 g) and in the AIA + cashew nut oil group (192.4 \(\pm\) 15.093) was also significantly (\(p\) = 0.094, \(p\) = 0.009, respectively) lesser than those in the AIA group. Effect of Different Nuts' Oil on the Morphological Appearance in Adjuvant-Induced Arthritis (AIA) Rat Model  
Figure 3A-F shows the morphological appearance of the back paw in all groups of rats. Swelling, redness, and stiffness in digits, as well as joint deformities, were observed in AIA-induced rats (Figure 3B) fed a normal diet versus control rats (Figure 3A) fed a normal diet. Feeding the rats a diet rich in walnut, peanut, cashew, and hazelnut oils significantly reduced the degree of redness, swelling, joint deformities, and paw pain in all AIA-induced rats (C-F) versus AIA-induced rats fed on a normal diet containing soybeans as a fat source (B). Figure 3: Effect of different nuts’ oil on the morphological appearance of the back paw from all groups of rats.