# Laminar _Ulva_ Species: A Multi-Tool for Humankind?
## 5 Commercial Potential
### Agriculture and Livestock Animals  
Historically, seaweed has been used not only for human food but also for animal food since the 19 th and early 20 th centuries in several European countries, such as Norway, Scotland, and France, and in America. These feeds were used for cattle, horses, and poultry [70].  
[PERSON] et al., 2013 [175] found that including _U. lactuca_ (up to 3%) in maize diets for 21 days showed no detrimental impacts on assessed chicken production parameters but enhanced carcass features in terms of yield and breast yield [70; 157].  
References in [PERSON] and [PERSON] 1998 [176] and [PERSON] et al., 2017 [177] showed that nutritional assessment of _U. lactuca_ for goats and sheep helps its presence as medium-quality forage [4]. [PERSON] and [PERSON] 2011 [178] and [PERSON] and [PERSON] 2005 [179] state that the use of macroalgae in feed led to an increase in milk output in cattle and the growth rate in lambs and an improvement in the color of the yolk in eggs [180].  
In terms of marine animals, past research in fish aquaculture has shown that integrating green algae in their diet improves fish development, with _Ulva_ biomass being mostly used as feed for abalone, shrimp, and fish aquaculture. For example, [PERSON] and [PERSON] 1992 [181] showed that incorporation of 5% _Ulva_ spp. in Snakehead Murrel feeding increased growth rate, feed efficiency, and feed consumption [70]. [PERSON] et al., 1995 [182] showed that the body weight improvement and feed effectiveness of red sea bream _Pagurus major_ was boosted by the adding of 5% algae meal. Furthermore, [PERSON] and [PERSON] 1998 [183] found that Atlantic salmon (_Salmo salar_) fed Ascophyllum nodosum had significantly higher levels of lysozyme (3.28 \(\pm\) 0.49 g mL\({}^{-1}\)) compared to controls (2.99 \(\pm\) 0.65 g mL\({}^{-1}\)). This suggests that alginate has an immunositulant effect, improving stress response and disease resistance in marine animals. According to [PERSON] et al. (2006) [184], abalone fed a mixed diet of _U. lactuca_, _Gracilaria gracilis_, and kelp exhibited a growth rate of 0.066 mm per day in shell length and 0.074 g per day in body weight. However, abalone fed solely dried kelp showed a lower growth rate, with only 0.029 mm per day in shell length and 0.021 g per day in body weight [93; 184].  
The alga _A. nodosum_ is also used in agriculture, commonly found on the northwestern coast of Europe and in the northwest of North America. Its extensive use is mainly due to its abundance, ease of collection, and growth in areas close to processing infrastructures [180]. It has already been demonstrated in [PERSON] et al., 2014 [185] and [PERSON] et al., 2017 [186] that commercial hydrolyzed extracts of _A. nodosum_ (ANE) exhibit growth-stimulating activities in treated plants, when repeatedly applied at very low doses, and are called \"biostimulants\". [PERSON] 2008 [187], [PERSON] et al., 2009 [188], [PERSON] et al., 2010 [189], and [PERSON] et al., 2018 [190] mention that foliar spraying improved the quality of fruits of watermelons, apples, olives, and grapes [191].  
Another use is as a natural biopesticide, where it can control pests and diseases. There are several bibliographies from which we can take the following examples: in [PERSON] and [PERSON] 1990 [192], a reduction of the population of two-spotted red spider mites on treated plants on strawberry crops occurred; in [PERSON] et al., 2011 [193], it is demonstrated that it decreases the advancement of diseases, which is connected with the expression of jasmonic-acid-related gene transcript in _Pseudomonas syringae_ and _Sclerotinia sclerotium_, on _Arabidopsis_ crops; and in [PERSON] and [PERSON] 2016 [194], tomato crops stimulate the appearance of defense-related genes or proteins off _Plytophthora capsaicin_[191].