Effect of Potato Vine and Leaf Mixed Silage Compared to Whole Corn Crops on Growth Performance, Apparent Digestibility, and Serum Biochemical Characteristics of Fattening Angus Bull

Abstract

This study aims to explore the different growth performances of the Angus bull on potato vine and leaf mixed silage in the early fattening period and to provide a reference animal production trial. Thirty-six 13-month-old Angus bulls were divided into three groups with 403.22 ± 38.97 kg initial body weight and fed with three different silage diets: (1) control: whole-plant corn silage as control (CS); (2) treatment 1: 50% whole-plant corn +50% potato vine and leaf silage (PVS1); and (3) treatment 2: 75% potato vine and leaf +15% rice straw +10% cornmeal silage (PVS2). After the 14 days pre-feeding, the formal experiment was carried out for 89 days. The result showed that the ash content of the potato vine and leaf mixed silage (PVS) in the treatment groups was higher than that in control group, and the ash content of PVS1 and PVS2 even reached 10.42% and 18.48% (DM%), respectively, which was much higher than that of the CS group at 4.94%. The crude protein content in silage also increased with the additional amount of potato vine and leaf. The apparent crude protein digestibility of the PVS groups was also significantly higher than that of the CS group (p < 0.05). In terms of serum biochemical indexes, blood urea nitrogen (BUN) in the experimental groups was significantly higher than in the control group (p < 0.05). Compared with PVS2, cholesterol (CHO) was significantly lower in the CS and PVS1 groups (p < 0.05). Moreover, the high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) of PVS2 were significantly higher than those of the CS and PVS1 group (p < 0.05), and daily gain (ADG) as a key production index had a significantly negative correlation with the CHO (r = -0.38, p < 0.05) and HDL-C (r = -0.40, p < 0.05) of cattle. In conclusion, PVS had higher crude protein content and ash but less starch than whole-corn silage. The PVS could replace whole-plant corn silage at the same dry matter status and did not affect the weight gain in this trial.

Keywords: beef cattle; growth performance; nutrients metabolism; potato vine and leaf mixed silage.

Figure 1

Serum antioxidant indexes of Angus beef cattle under three different silages. (a) This figure shows the superoxide dismutase value in the beef cattle serum of three groups (CS, corn silage; PVS1, potato vine and leaf mixed silage 1; PVS2, potato vine and leaf mixed silage 2). (b) This figure shows the malondialdehyde value in the beef cattle serum of three groups. (c) This figure shows the glutathione peroxidase value in the beef cattle serum of three groups. (d) This figure shows the catalase value in the beef cattle serum of three groups. (e) This figure shows the total antioxidant capacity value in the beef cattle serum of three groups. (f) This figure shows the reactive oxygen species value in the beef cattle serum of three groups. (g) This figure shows the oxidative stress index value in the beef cattle serum of three groups. SOD, superoxide dismutase, U/mL; MDA, malondialdehyde, nmol /mL; GSH-PX, glutathione peroxidase, U/mL; CAT, catalase, U/mL; T-AOC, total antioxidant capacity, U/mL; ROS, reactive oxygen species, U/mL; OSI, oxidative stress index, OSI = ROS/T-AOC. The bar chart shows the mean and SEM for each indicator; the error line is the positive standard error value.

Figure 1

Serum antioxidant indexes of Angus beef cattle under three different silages. (a) This figure shows the superoxide dismutase value in the beef cattle serum of three groups (CS, corn silage; PVS1, potato vine and leaf mixed silage 1; PVS2, potato vine and leaf mixed silage 2). (b) This figure shows the malondialdehyde value in the beef cattle serum of three groups. (c) This figure shows the glutathione peroxidase value in the beef cattle serum of three groups. (d) This figure shows the catalase value in the beef cattle serum of three groups. (e) This figure shows the total antioxidant capacity value in the beef cattle serum of three groups. (f) This figure shows the reactive oxygen species value in the beef cattle serum of three groups. (g) This figure shows the oxidative stress index value in the beef cattle serum of three groups. SOD, superoxide dismutase, U/mL; MDA, malondialdehyde, nmol /mL; GSH-PX, glutathione peroxidase, U/mL; CAT, catalase, U/mL; T-AOC, total antioxidant capacity, U/mL; ROS, reactive oxygen species, U/mL; OSI, oxidative stress index, OSI = ROS/T-AOC. The bar chart shows the mean and SEM for each indicator; the error line is the positive standard error value.

Figure 2

Heatmaps of Spearman correlation analysis. The correlation heatmap is used to represent significant statistical correlation values (r) between growth performance and biochemical indexes. In the heatmap, blue squares indicate significant positive correlations (r > 0.5, p < 0.05), white squares indicate non-significant correlations (p > 0.05), and red squares indicate significant negative correlations (r < −0.5, p < 0.05). * p < 0.05, ** p < 0.01, and *** p < 0.001.