Total nutrient digestibility and small intestine starch digestion in Nellore and Angus young bulls fed a whole shelled corn diet

Abstract

Eighteen Nellore and 18 Angus young bulls with BW of 381 ± 12 kg were randomly assigned into two feeding groups (whole shelled corn [WSC] or ground corn with silage [GC]) to evaluate the interaction of breed and diet on total nutrient digestibility, pancreatic α‐amylase, and maltase activity and SLC5A1expression in the small intestine. Experimental diets (DM basis) included (a) a diet containing 30% corn silage and 70% GC and soya bean meal‐based concentrate and (b) a diet containing 85% WSC and 15% of a soya bean meal‐ and mineral‐based pelleted supplement. The treatments were Nellore fed GC diet; Nellore fed WSC diet; Angus fed GC diet; and Angus fed WSC diet. Total faecal collection for the digestibility trial occurred from day 48 until day 50 of the experimental period. Feeding the WSC diet reduced DM and NDF intake (p < 0.01). Angus had greater DM and nutrient intake in kg/day (p < 0.01). However, there was no breed effect on DM and nutrient intakes based on percentage of BW (p > 0.19). Angus had greater starch digestibility (p = 0.03) than Nellore. Cattle fed the WSC diet had greater DM, NDF and starch digestibility (p < 0.01) compared with those fed the GC diet. The activity of pancreatic α‐amylase (U/g of protein) was greater in Nellore (p < 0.01) and was not affected by diet (p = 0.52). In duodenum, maltase activity (U/g of protein) was greater in bulls fed GC diet (p = 0.02). Expression of the gene SLC5A1was not affected by breed or diet (p > 0.05). In conclusion, Nellore had less capacity to digest starch. However, they did not have less pancreatic α‐amylase and duodenal maltase activity compared to Angus. The use of the WSC diet increases DM and total nutrient digestibility.

Performance, carcass characteristics, and ruminal pH of Nellore and Angus young bulls fed a whole shelled corn diet1

“…Moreover, Angus bulls had greater G:F than Nellore bulls (P < 0.01). These results may be explained by the better use of starch in the gastrointestinal tract of Angus bulls compared with Nellore bulls (Carvalho, 2015).…”

“…Chemical analyses of the diets were performed according to the Association of Official Analytical Chemists (1990) for CP (method 920.87), Sniffen et al (1992). 5 ME = TDN (g/kg DM) × 4.4 × 0.82 (Carvalho, 2015).…”

Increasing roughage quality by using alfalfa hay as a substitute for concentrate mitigates CH4 emissions and urinary N and ammonia excretion from dry ewes

“…In this study, the NDF content was not affected by an increase in alfalfa input level (571, 558 and 562 g/kg for AH0, AH15 and AH30, respectively, p > .1), which might be the main reason for the similar DM intake between the benchmark and alfalfa diets. Meanwhile, compared with concentrate, the longer particles of alfalfa increased the rumination and salivation of animals, which also contributed to similar DM intake (Carvalho et al, 2019). Note: a, b and c: means within the same row and with the same letters are not significantly different (p > .05).…”

“…Studies have shown that the problem of low microbial protein yield with poor-quality roughage-based diets cannot be simply solved or completely compensated by supplementation with high amounts of concentrates (Pathak, 2008), and high concentrate input also increases the risk of metabolic disorders (Tayyab, Wilkinson, Charlton, Reynolds, & Sinclair, 2019). Meanwhile, steadily increasing the demand for milk and meat much coming from ruminants would increase the proportion of food used as feed against the background of limited available arable land and further exacerbation of global climate change, with more than 13.3% of the world's cereal grains being offered to ruminants (Eisler et al, 2014) and with this proportion increasing in areas such as Brazil (Carvalho et al, 2019) and China. Meanwhile, steadily increasing the demand for milk and meat much coming from ruminants would increase the proportion of food used as feed against the background of limited available arable land and further exacerbation of global climate change, with more than 13.3% of the world's cereal grains being offered to ruminants (Eisler et al, 2014) and with this proportion increasing in areas such as Brazil (Carvalho et al, 2019) and China.…”

“…Increasing the forage quality could improve concentrate-sparing effect (Keady & Hanrahan, 2015), and the response in improving intake and digestibility from concentrate input could be overridden by high-quality forage (Ramos, Tejido, Martínez, Ranilla, & Carro, 2009;Wang et al, 2019). Meanwhile, steadily increasing the demand for milk and meat much coming from ruminants would increase the proportion of food used as feed against the background of limited available arable land and further exacerbation of global climate change, with more than 13.3% of the world's cereal grains being offered to ruminants (Eisler et al, 2014) and with this proportion increasing in areas such as Brazil (Carvalho et al, 2019) and China. The increased demand for grain in feedlots is increasing the demand for agricultural lands, thereby adding pressure to the conversion of native ecosystems to agriculture, with further considerable environmental impacts at regional and global scales (McAlpine, Etter, Fearnside, Seabrook, & Laurance, 2009).…”