Usability of rapeseed cake and wheat-dried distillers’ grains with solubles in the feeding of growing Californian rabbits

Abstract

By-products of biofuels production such as rapeseed cake and dried distillers' grains with solubles (DDGS) may constitute valuable feedstuffs for livestock. The objectives of the study were to determine the usability of these components in the feeding of growing rabbits and to assess their impact on physiological changes in the gastrointestinal tract of the animals. Sixty-four rabbits were divided into four feeding groups: Control (5% soyabean meal [SBM] in the diet), R (5% rapeseed cake [RSC]), DDGS (5% wheat DDGS), and R/DDGS (2.5% RSC and 2.5% wheat DDGS). The study included a production experiment, a digestibility-balance experiment and physiological assessment of the functioning of animals' gastrointestinal tract (small intestine, caecum and colon). No statistically significant differences were determined in production results of the rabbits. Digestibility of nutrients and energy and nitrogen retention were the highest in the Control and the lowest in Group DDGS. Group DDGS was characterised by the highest relative weight of small intestine and digesta. In turn, Group R was characterised by the highest degree of caecal digesta hydration and bulking and by the highest pH value and the lowest concentration of VFA in caecum. The activity of selected bacterial enzymes released to the caecal environment was similar in all groups; however, the activity of α-arabinopyranosidase was significantly increased in Groups R and DDGS. Worthy of notice is the enhanced enzymatic activity of colonic microbiota in the R/DDGS group which has a positive effect upon increased utilisation of dietary nutrients compared to the DDGS group. The obtained results indicate that SBM from rabbit diets may be successfully replaced by 5% RSC as well as by 2.5% RSC + 2.5% wheat DDGS.

The effect of substitution of soybean meal with a mixture of rapeseed meal, white lupin grain, and pea grain on performance indicators, nutrient digestibility, and nitrogen retention in Popielno White rabbits

“…However, they were lower than those for typical meat rabbits kept under similar conditions and fed feeds with a similar nutritional value (Strychalski, Juśkiewicz et al 2014;Gugołek et al 2015). Based on the data presented above, it should be considered that both partial and complete elimination of extracted SBM from the rations, and the substitution thereof with extracted RSM, WL, and peas, had no effect on the production results of rabbits.…”

“…For example, Gasmi- et al (2007) demonstrated in their study that 7% dietary inclusion of RSM had no effect on production results. Results of experiments conducted by Strychalski, Juśkiewicz et al (2014) and Gugołek et al (2015) demonstrated that the replacement of SBM with 5% of rapeseed cake did not cause changes in daily BWG, FCR, or DP of rabbits. Volek and Marounek (2009) showed that the addition of 15% WL grain to the rabbits' feed did not affect weight gain or FCR as compared to that in animals fed diets containing SBM.…”

“…The results of a study carried out by Gasmi-Boubaker et al (2007) demonstrate that a 7% addition of RSM to feed mixtures for rabbits had no effect on the DN, which is consistent with the results of our experiment. On the other hand, studies by Strychalski, Juśkiewicz et al (2014) and Gugołek et al (2015) demonstrated that the substitution of 5% SBM with RSM slightly reduced the digestibility of TP, EE, and GE. On the other hand, Volek and Marounek (2009) and Volek et al (2013) demonstrated that the addition of 15% WL grain and 5% WL grain hulls to the ration had no effect on the DN.…”

“…Similar results were achieved by Daszkiewicz et al (2012) in New Zealand White Rabbits, in an extensively fed group. In turn, as regards typical rabbits bred for meat, the slaughter yield calculated using this method is usually higher, and exceeds 50% (Zita et al 2007;Volek & Marounek 2009;Gugołek et al 2011;Strychalski, Juśkiewicz et al 2014;Gugołek et al 2015).…”

“…Most often, they were by-products of the agro-food industry. The use of barley, wheat, and corn dried distiller grains with solubles (DDGS) (Chełmińska & Kowalska 2013;Alagón et al 2014;Strychalski, Juśkiewicz et al 2014;Gugołek et al 2015), sunflower cake (Volek & Marounek 2009;Volek & Marounek 2011), and rapeseed cake (Dänicke et al 2004;Gasmi-Boubaker et al 2007;Strychalski, Juśkiewicz et al 2014;Gugołek et al 2015) has already been studied. Moreover, attempts to use the grain of white lupin (WL) (Volek & Marounek 2009;Volek & Marounek 2011;Volek et al 2013), pea (Seroux 1988;Castellini et al 1991;Bonomi et al 2003), and other plants of the Fabaceae family have been made (Amaefule et al 2005;Lounaouci-Ouyed et al 2014).…”