RESEARCH ARTICLE Effect of calcium lignosulfonate supplementation on metabolic profiles of confined lambs Maria Luiza França Silva 1 & Gleidson Giordano Pinto de Carvalho 2 & Robério Rodrigues Silva 1 & Tamires da Silva Magalhães 2 & Pablo Teixeira Viana 1 & Luana Marta de Almeida Rufino 3 & Aracele Vieira Santos 2 & José Augusto Gomes Azevedo 4 & José Esler Freitas Júnior 2 & Camila de Oliveira Nascimento 2 & Carlos Emanuel Eiras 2 Received: 21 November 2017 /Accepted: 24 April 2018 # Springer-Verlag GmbH Germany, part of Springer Nature 2018 Abstract This study aimed to evaluate the effect of calcium lignosulfonate associated with whole cottonseed in high-concentrate diets for sheep. Eight Dorper crossbred sheep with an average live weight of 42.5 ± 1.70 kg were assigned to two 4 × 4 Latin squares. The following experimental diets were evaluated: control diet (without calcium lignosulfonate) and diets with inclusion of 50, 100, and 150 g of calcium lignosulfonate/kg fresh matter. Diets were composed of soybean meal, ground corn, and whole cottonseed. Feed intake, digestibility, metabolic characteristics, and feeding behavior were evaluated. The intake of nutritional components did not show significant differences as a function of the lignosulfonate levels in the diet; however, the increase in calcium lignosulfonate levels linearly decreased the dry matter digestibility. Rumen ammonia nitrogen concentrations decreased linearly as the lignosulfonate levels in the diets were increased. There was no effect of lignosulfonate levels on blood parameters or feeding behavior of the animals. The use of lignosulfonate associated with cottonseed decreases the digestibility of dry matter and the concentration of rumen ammonia nitrogen, but does not change the intake of nutritional components, the blood parameters, or the feeding behavior of sheep. Keywords Methane . Rumen biohydrogenation . Volatile fatty acids Introduction Because of their high energy density, oilseeds are the most widely used lipid sources in ruminant diets. As such, they can replace rapidly fermentable carbohydrates and benefit the rumen fermentation and the fiber digestion (Capper and Buaman 2013). Among the oilseed sources available, the cottonseed stands out for its lipid potential. According to Valadares Filho et al. (2002), this by-product has desirable characteristics to be included in ruminant feeding, such as high protein (20% crude protein) and energy (23% ether extract and 82.8% total digest- ible nutrients) contents. Additionally, it has a highly degrad- able effective fiber, known as linter (Harvatine et al. 2002), and does not require processing. Its lipid fraction is composed primarily of unsaturated fatty acids like oleic, linoleic, and linolenic acids (Palmquist 1991). Despite its favorable nutritional and economic characteris- tics, the lipid content of cottonseed can change the rumen fermentation. This response is caused by the toxic effect of the unsaturated fatty acids, present in the lipids, on gram- positive microorganisms in the rumen, such as fibrolytic bac- teria (Van Soest 1994; Moallem et al. 2007; Palmquist 2007), and the physical effect of lipids on the food particles, creating a barrier that prevents or complicates microbial adhesion, thereby compromising the fiber digestion (Jenkins 1993; Jenkins et al. 2008). A way to minimize the negative effects of unsaturated fatty acids on the rumen microbiota is to provide animals with lipid sources protected with additives. In this regard, because of the agglutinating properties of calcium, it is believed that the use Responsible editor: Philippe Garrigues * Gleidson Giordano Pinto de Carvalho gleidsongiordano@yahoo.com.br 1 State University of Southeast Bahia, Itapetinga, Bahia, Brazil 2 Federal University of Bahia, Salvador, Bahia, Brazil 3 Federal University of Pará, Castanhal, Pará, Brazil 4 State University of Santa Cruz, Ilhéus, Bahia, Brazil Environmental Science and Pollution Research https://doi.org/10.1007/s11356-018-2121-0