## 4 Discussion  
The CP content of SH (14.9%) in this study was higher than that reported in other studies [23]. This might be due to seasonal and regional differences [24]. According to [PERSON] et al. [24], the fluctuation of nutrient content in seaweed by season corresponds with its growth cycle, in which protein and lipid content correlate with an increase in ash content. Seaweed can contain non-protein nitrogen compounds, such as free nitrates, which  
Figure 2: The effect of blanning temperature and supplementation level on total gas emission, CO\({}_{2}\), and CH\({}_{4}\) of _Sargassum horneri_ in the rumen incubated for 48 h. CON, _Sargassum horneri_ blunched in cool water (21 \({}^{\circ}\)C) for 3 min; LOS, _Sargassum horneri_ blunched in water at 70 \({}^{\circ}\)C for 3 min; 0, 1, 3, and 5%, supplemented levels of _Sargassum horneri_. The significances of temperature, level, and temperature \(\times\) level on total gas mL/g DMD are \(p<\) 0.001, \(p=\) 0.002, and \(p=\) 0.023, respectively. The significances of temperature, level, and temperature \(\times\) level on total gas mL/g DMD are \(p<\) 0.001, \(p=\) 0.003, and \(p=\) 0.081, respectively. The significances of temperature, level, and temperature \(\times\) level on CO\({}_{2}\) mL/g DMD are \(p=\) 0.001, \(p=\) 0.305, and \(p=\) 0.759, respectively. The significances of temperature, level, and temperature \(\times\) level on CO\({}_{2}\) mL/g DMD are \(p=\) 0.945, \(p=\) 0.638, and \(p=\) 0.885, respectively. The significances of temperature, level, and temperature \(\times\) level on CH\({}_{4}\) mL/g DMD are \(p<\) 0.001, \(p=\) 0.010, and \(p=\) 0.153, respectively. The significances of temperature, level, and temperature \(\times\) level on CH\({}_{4}\) mL/g DMD are \(p=\) 0.259, \(p=\) 0.169, and \(p=\) 0.281, respectively. \({}^{\alpha-}\) Means in the same CON treatment with different superscripts differ significantly (\(p<\) 0.05). \({}^{\mathrm{A,B}}\) Means in the same LOS treatment with different superscripts differ significantly (\(p<\) 0.  
may result in a relatively high measured protein value compared to ordinary plants [5]. Furthermore, brown seaweed is richer in CA and mineral content than other seaweeds [25]. In the current study, the blanching process (temperatures or times) of SH increased the CP, NDF, and ADF content and decreased the CA content compared to cool tap water washing, which aligns with previous studies that reported similar results when blanching kelp [7]. The significant reduction of CA content observed in this study through the blanching led to increased CP, NDF, and ADF fractions. This result could enhance the nutritional feed value of SH by demonstrating a means to increase the supply of dietary protein and fiber to the ruminants. Moreover, unblanched ingredients can have undesirable changes in sensory characteristics and nutritional value during storage [26]. Seaweed has a high mineral content and exceptionally high salt concentration to preserve its cell membrane due to its oceanic habitat [27]. Thus, in order to use it as a feed source, seaweeds should be screened carefully to prevent excessive intakes of salt, iodine, and heavy metals. Generally, toxicoses of livestock can be caused by high amounts of undesirable minerals (As, K, Pb, etc.) in their diets. The As and Pb can disrupt the balance of other minerals in the body, while Na can also impact minerals that alter acid-base and electrolyte balance [28]. The Na and K levels have the potential to affect feed intake [3], and the high concentration of Na and K in the _Sargassum_ sp. may increase the water consumption of ruminants, which is not beneficial for feeding during the dry period [29]. Every thermal process is detrimental to the integrity of plant tissue, particularly the cellular membranes of seaweed [30]. The present study showed that the concentrations of Na, K, and As decreased as the blanching temperature increased. According to [PERSON] et al. [7] and [PERSON] et al. [6], minerals on the surface of seaweed dissolve during the blanching process.