Scielo RSS <![CDATA[South African Journal of Animal Science]]> vol. 52 num. 2 lang. en <![CDATA[SciELO Logo]]> <![CDATA[<b>An exogenous fibrolytic enzyme mixture enhances in vitro ruminai degradability of red grape pomace by-product</b>]]> Usefulness of red grape pomace (GP) by-product in ruminant rations is restricted by its high fibre content. Pre-treatment with exogenous carbohydrases may partly resolve this problem. Therefore, the effects of various levels of an exogenous fibrolytic enzyme mixture (Viscozyme® L) on chemical nutrient content and in vitro ruminal fermentation of GP were studied. This product, with an enzyme activity of >100 fungal beta-glucanase per gram (FBG/g) and a density of 1.2 g/mL, was applied to GP at 0 (ENZ0), 20 (ENZ20), 30 (ENZ30), 35 (ENZ35), and 45 g/kg DM (ENZ45). Neutral detergent fibre (NDF), acid detergent fibre (ADF) and insoluble condensed tannins (ICT) declined linearly as enzyme levels increased. Significant negative linear trends were observed for the rate of gas production at 36 and 48 hours, whereas quadratic trends were observed at 12- and 24-hours incubation in response to enzyme levels. Cumulative gas production at 12 hours and 24 hours and in vitro organic matter degradability at 96 hours post incubation increased linearly as treatment levels increased. Effective gas production declined linearly (P =0.041; R² =0.085), whereas the slowly degradable fraction (P =0.042, R² =0.084), the fractional degradation rate (P =0.003, R² =0.175) and potential gas production (P =0.043, R² =0.083) showed quadratic trends as enzyme levels increased. Pre-treatment with Viscozyme reduced the fibre levels of GP and increased in vitro ruminal organic matter degradability. The optimum level for inclusion of Viscozyme was 5 g/kg. <![CDATA[<b>Influence of graded level of salt and maturation times on quality traits of beef and pork sun-dried meat: A test pilot</b>]]> The goal of this study was to assess the qualitative and sensorial characteristics of beef and pork sun-dried meat (SDM) with different salt (NaCl) levels (6%, 8% and 10%) and curing times (30 and 40 h). Samples from the beef strip loin (Gluteus medius) and pork loin (Longissimus thoracic) were cut to a thickness of 5 cm. Three levels of salt were applied, and the meat was allowed to cure for either 30 or 40 hours with three replications per treatment. The pH, shear force (SF), luminosity (L*), tonality (TON), saturation, loss of water by cooking (LWC), moisture, crude protein (CP), sensory attributes, and consumers' intention to buy were analysed. Beef and pork produced differences in L*, saturation, TON, and CP, appearance, and colour of the sun-dried product. The SDM cured for 30 hours was higher in moisture, LWC and L* (P =0.023), and had greater CP content than that cured for 40 hours. The appearance and salinity of the product were affected by the level of salt that was used in making it. In conclusion, various NaCl levels did not influence the physical-chemical and qualitative characteristics of the SDM, but these characteristics were influenced by the curing and meat type. In addition, the meat type and the salt level affected some aspects of the sensory evaluation. <![CDATA[<b>Dry sugarcane yeast and urea could replace soybean meal in the diet of buffalo heifers</b>]]> The aim of this study was to examine the effects of replacing soybean meal (SBM) with increasing levels (0%, 33%, 67%, and 100%) of sugarcane yeast and urea on the intake, performance, and feeding behaviour of buffalo heifers. Twenty Murrah female buffalos with an initial average weight of 157 ± 1.9 kg at 7 months old were distributed in a completely randomized design. The experimental period was 84 days, and was preceded with 30 days of adaptation. Data were subjected to analysis of variance and regression, using the GLM and REG procedures of SAS software at 5% probability level. The replacement of SBM with sugarcane yeast did not have a significant effect on the intake of dry matter (DM), organic matter and crude protein (CP). Non-fibrous carbohydrate intake increased linearly, whereas the intake of neutral detergent fibre (NDF), and ether extract (EE) decreased linearly. There was no treatment effect on average daily gain or feed conversion (FCR). Rumination efficiency on nondetergent fibre (NDF) decreased linearly. The times spent ruminating, remaining idle, and feeding were not influenced by the treatments, and neither were the parameters of feeding efficiency as a function of DM and NDF intakes and rumination efficiency as a function of DM intake. Dry sugarcane yeast and urea could replace SBM fully in the diet of buffalo heifers with a roughage to concentrate ratio of 50 : 50, because animal performance would not be affected. <![CDATA[<b>Rumen microbial diversity of Bonsmara cattle using amplicon sequencing during a 120-day growth trial</b>]]> Improved understanding of the microbial populations during intensive feeding of feedlot cattle holds potential for optimizing production efficiency. Ionophores are used to increase the production and efficiency of ruminants and are commonly used in South African feedlots. Bonsmara bull calves (n=24) were subject to a four-phase feedlot diet in a growth trial commencing with backgrounding, followed by starter, grower and finisher diets. Animals were randomly divided into two groups: control and a group provided the in-feed ionophore monensin. Four animals from each group were randomly selected for rumen content collection using an oesophageal tube during the phases in the trial. Samples were analysed using 16S rRNA and internal transcribed spacers amplicon sequencing. Totals of 42 008 and 35 442 amplicon sequence variants were identified from 16S rRNA and internal transcribed spacers amplicon sequencing. The rumen microbiome composition and alpha diversity differed significantly between the phases, whereas no significant difference was observed between the control and monensin groups. Backgrounding had the highest bacterial richness, whereas the grower phase had the highest fungal richness. Bacteroidetes, Firmicutes and Proteobacteria were the most abundant phyla, with Bacteroidetes being most abundant in the backgrounding and starter phases, whereas Proteobacteria was the most abundant in the grower and finisher phases. Ascomycota, Basidiomycota and Neocallistigomycota were the most abundant fungal phyla. Improved knowledge of the shift in microbiome population during the growth period could assist in adapting feeding strategies to improve the efficiency of beef production.