Effects of a fibrolytic enzyme and bacterial inoculants on the fermentation, chemical composition and aerobic stability of ensiled potato hash

The study was conducted to evaluate the effects of adding a fibrolytic enzyme in combination with bacterial inoculants on the fermentation, chemical composition and aerobic stability of ensiled potato hash (PH). Potato hash silage (PHS) was produced by mixing 800 g PH/kg and 200g wheat bran (WB)/kg. The mixture was ensiled with either no additive or enzyme Celluclast (low or high dose) or bacterial inoculants (Emsilage and Silosolve). These treatment combinations were produced: i) no additive (control); ii) Celluclast low dose (CLD); iii) Celluclast high dose (CHD); iv) Emsilage (EMS); v) CLD + EMS; vi) CHD + EMS; vii) Silosolve (SLS); viii) CLD + SLS; and ix) CHD + SLS. These treatments were ensiled in 81 x 1 L anaerobic jars for 90 days with nine replicates per treatment. Three samples per treatment were collected before ensiling and after 90 days’ ensiling, were analysed for fermentation characteristics and chemical composition. In addition, samples of day 90 were subjected to an aerobic stability test, where they were exposed for five days. Enzyme addition reduced fibre, thus making more sugar available for fermentation. The combination of CHD and EMS reduced silage pH, thus preserving the silage compared with other treatment combinations. Enzyme addition (used at low and high dose), and bacterial inoculants improved fermentation. Enzyme addition improved the chemical composition, but impaired the aerobic stability of PHS. Further work to test these findings on animal performance is warranted.Keywords: Deterioration, fibre, nutrients, pH, ruminant, water soluble carbohydrate

Systemicity of banana bunchy top viral infection in the Kisangani region of the Democratic Republic of Congo

In order to evaluate the systemicity of BBTV from one plant of the mat to the physically attached shoots, 60 mats both of “Yangambi Km5”, Musa AAA and those of the false horn plantain “Libanga Likale”, Musa AAB showing severity levels from 0 to 5 were selected in backyards in Kisangani. In addition, 30 sucker corms per genotype were put under macro-propagation and leaf samples of lateral shoots that had emerged were tested using triple antibody sandwich-enzyme linked immuno sorbent assay (TAS-ELISA). In the backyards, for mats with no visible banana bunchy top disease (BBTD) symptoms, none of the analyzed mats with a total of 29 plants of “Yangambi Km5” and of 35 plants of “Libanga Likale” tested ELISA positive, indicating the absence of the BBTV infection. However, for the severity levels of one to five, 32 to 63.5% of plants in the mats were ELISA positive for “Yangambi Km5”, while 34.9 to 73.2% of plants from “Libanga Likale” tested positive for BBTV. After macro-propagation, 100% of lateral shoots of both cultivars at BBTD severity levels 4 and 5 tested positive. On the other hand, none of the lateral shoots at level 0 tested ELISA positive. However, for levels 1 to 3 some ELISA negative plantlets (40 to 23% for “Yangambi Km5” and 53 to 15% for “Libanga Likale”) were observed. This study indicates the need for the complete destruction of all mats harbouring plants with BBTD severity levels of 3, 4 and 5. Macro-propagation of suckers with severity level 1 symptoms could produce virus-free plantlets but ELISA testing of the lateral shoots is essential to pinpoint the virus-free plantlets

Dietary inclusion of ensiled avocado oil cake affects growth, nutrient digestion, and carcass characteristics of pigs

In this experiment, the effects were evaluated of various dietary inclusion levels of avocado oil cake (AOC) silage on growth performance, nutrient digestibility, and carcass characteristics in pigs. A mixture of 70% AOC, 25% wheat bran, and 5% sugarcane molasses was ensiled in 200 L drums for 90 days. It was then incorporated at 0%, 3% and 5% in the experimental diets. Twenty-seven Large White cross Landrace (LW x LR) weaner pigs, with an average live weight of 22 kg, were stratified by weight and randomly allocated to the three experimental diets (9 pigs/diet). Pigs were weighed individually each week throughout the trial. Daily feed intake, average daily gain (ADG) and feed conversion rates (FCRs) were recorded. A nutrient digestibility study was carried out on completion of the growth trial. At the end of the experiment, pigs were fasted for twelve hours and weighed to determine the final weight. The pigs were then slaughtered, and carcass samples were collected and analysed. The growth performance of pigs was not affected by diet, irrespective of fibre levels in the AOC silage. However, the addition of 3% AOC silage improved the digestibility of fibre fractions. The weights of the cold carcass, chops, and backfat thickness were reduced with AOC silage addition

Effects of silage sealing films on fermentation dynamics of ensiled maize and nutrient utilization by Damara rams

An experiment was conducted to evaluate the effects of two silage sealing films on whole crop maize (WCM) fermentation, aerobic stability and nutrient digestion by rams. Prior to ensiling (day 0), triplicate samples of the WCM were collected to determine dry matter, pH, water-soluble carbohydrates (WSC), lactic acid (LA) bacterial counts and nutrient concentration. A single bunker silo was divided into eight sections that were ensiled using either a standard polyethylene film (PE) or an orange oxygen barrier (OB) Silostop film for 180 days. After 180 days of ensiling, six silage samples were collected from each replicate. Three samples were used for nutrient analysis and the other three to determine aerobic stability. Sixteen four-year-old Damara rams with an average live weight of ± 54 kg were housed individually in wooden pens (2.2 m2) to determine digestibility of nutrient in the silage. The digestibility study was conducted as a switchover design with four feeding phases. The silage was supplemented daily with 1% urea and fed to the rams ad libitum. Nutritional value of the silage was not (P >0.05) affected by the ensiling films. The OB-ensiled maize had higher (P 0.05) by treatments. The OB film improved the fermentation and aerobic stability of WCM silage but did not influence its nutrient utilization by rams.The National Research Foundationhttp://www.sasas.co.zaam2021Animal and Wildlife Science

Effects of whey and molasses as silage additives on potato hash silage quality and growth performance of lambs

The aim of the study was to determine the effect of whey or molasses on the fermentation quality when added to potato hash silage. In addition, lamb performance, digestibility and feed intake of diets containing potato hash silage were compared with a diet containing maize silage (MSd). Potato hash silage (treated with no additive, or whey, or molasses) and MS were produced in 210 L drums for 90 days and the fermentation quality of the silages was determined thereafter. Diets were formulated and fed ad libitum to 32 South African Dorper lambs (23.5 ± 0.873 kg live weight) for 63 days. A digestibility study was conducted during the last week of the study. The untreated potato hash silage (UPHS) was poorly fermented as indicated by higher concentrations of butyric acid, ammonia-N and pH compared to the other silages. Higher dry matter intake (DMI) and daily weight gains (218 and 250 g/d) were obtained with MSd and molasses treated potato hash silage diet (MPHSd) compared to the other diets. Nutrient digestibility was lower in the UPHS diet compared to the other dietary treatments. It was concluded that the fermentation quality of potato hash was improved with the addition of whey and molasses. Furthermore, growth performance was higher with the MSd and MPHSd than of the other treatments, suggesting that MPHSd can safely replace MSd in a lamb diet at a dietary inclusion level of 20% without any adverse effect on animal performance.Keywords: Digestibility, dry matter, fermentation, intake, maize silag

The role of extension support in a communal farmers’ market system in Mhondoro-Mubaira, Zimbabwe

The objective of this research was to establish the role of agricultural extension in communal farmers’ market systems by looking at possible ways in which it could intervene and support communal farmers in the marketing of produce. The study was conducted in the area of Mhondoro-Mubaira, which is situated in Mashonaland West Province in Zimbabwe. The target population comprised of 150 communal farmers and 25 extension officers. Poor technology and an under-resourced extension department is one of the factors identified by the extension officers (84%) for poor extension delivery (p =<0.464). The communal farmers referred to in this study have a negative perception of government-led extension support, especially in the area of agricultural market support. About half (56%) of the farmers indicated that they do not receive any form of agricultural marketing extension support. The reasons for the poor ratings of government extension support by communal farmers include the following: they are hardly available (8.88%); they are not knowledgeable enough (13.02%); and they do not offer practical solutions (24.85%). Communal food production and food security could be significantly improved if farmers receive appropriate input, training and extension support. Market linkage from the extension department could effectively boost income from agriculture enterprises and upgrade communal farmers who come from the most vulnerable section of the country’s population.Keywords: Agricultural Extension Excellence Model (AEEM), Agritex, Communal farming, Extension, Market system

Microbial additives affect silage quality and ruminal dry matter degradability of avocado (Persia Americana) pulp silage

This study evaluated effects of microbial inoculation on fermentation, aerobic stability and ruminal dry matter (DM) degradation of silage produced from Avocado (Persia Americana) pulp (AP). The AP, 800 g/kg fresh matter (FM) was mixed with 150 g grape pumice (GP)/kg FM and 50 g sugarcane molasses/kg FM. The mixture was treated with 1) no inoculant (control), 2) Emsilage inoculant (EMS), and 3) Sil-All 4x4 W.S. inoculant (SIL). Materials were ensiled in 1.5 L anaerobic jars for 90 days. Triplicate samples were collected on days 0, 3, 7, 10, and 90 for determination of fermentation, nutritive value and aerobic stability. In situ DM degradability was determined using 3 rumen cannulated Holstein cows. Microbial inoculation to AP silage increased lactic acid bacteria population, which subsequently increased residual fermentation substrate and lactic acid content. Terminal pH and volatile fatty acids of the silage were not affected by inoculation. Inoculated silage had less fibre and reduced aerobic stability compared to the control. The AP and its mixture had higher DM soluble fractions compared to the GP which had a higher degradation rate. Potential degradable fraction and extent of degradation were similar for each treatment. The EMS treatment had higher soluble fractions and lower degradation rate than other treatments. Inoculation with SIL improved degradation of the silage compared to other treatments. Thus, microbial inoculation qualifies the AP silage as a potential feed for ruminants. Keywords: feed, grape pomace, inoculant, oil cake, organic aci

Growth performance, nutrient digestibility and carcass characteristics of pigs fed diets containing amarula (Sclerocarya birrea A. Rich) nut cake as replacement to soybean meal

This experiment evaluated varying levels of Amarula (Sclerocarya birrea A. Rich) nut cake (ANC) on growth performance, nutrient digestibility and carcass characteristics in pigs. Thirty Large White × Landrace (LW × LR) pigs were stratified by weight (average live weight of 20 ± 5 kg) and randomly allocated to the five experimental diets that contained 0 (control), 50, 100, 150 and 200 g ANC/kg DM. Each pig served as a replicate unit, housed individually. The pigs were fed the experimental diets ad-lib once in the morning, allowing a 10% of feed refusal, and had free access to water. Bodyweight, feed intake, average daily gain (ADG) and feed conversion ratio (FCR) were recorded weekly throughout the 56-day trial period. On completion of the growth trial, following a 3-day adaptation, a nutrient digestibility study was conducted over 5 days. Thereafter, pigs were fasted for 12 h, weighed, slaughtered, and carcass samples were collected for analysis. Data on the effects of treatments on growth performance, nutrient digestibility and carcass characteristics were analysed using a two-way ANOVA in randomised blocks and were compared using Student’s t-LSD. Feed intake was not affected by dietary treatment, but ADGs were reduced at ANC levels > 150 g/kg, resulting in poor FCR. Protein digestibility was reduced at ANC levels > 150 g/kg, while ether extract and fibre levels increased. Warm and cold carcass weights were lower at ANC levels > 150 g/kg, with improved meat redness and lightness. It was concluded that ANC could replace SBM in the diet of growing pigs at less than 150 g/kg inclusion level.The National Research Foundation of South Africahttp://link.springer.com/journal/112502022-12-10hj2022Animal and Wildlife Science