Growth performance, carcass characteristics and meat sensory evaluation of broiler chickens fed diets with fermented cassava leaves.

Objective: The objective of the study was to determine the effects of feeding fermented cassava leaf meal (FCLM) on growth performance, carcass characteristics and meat sensory evaluation of broiler chickens. Methods: A total of 160 Cobb-500 chickens were used during the phases of growing (21 days of age; initial weight 0.39 ± 0.025kg/bird) and finishing (35 days of age; initial weight 1.023 ± 0.164 kg/bird). The whole experiment lasted for four weeks. The FCLM was included in starter and finishing diets at 0, 50, 100, and 150 g/kg inclusion levels. Total feed intake (TFI), weight gain (WG), feed conversion ratio (FCR) and nutrient digestibility were recorded. Sensory evaluation of breast meat was used to determine the eating quality of the meat prepared using roasting and boiling methods. Results: The total feed intake (TFI) and weight gain (WG) decreased (P < 0.05) with increasing inclusion levels of FCLM in the diets of growing chickens. Crude protein digestibility for chickens fed 0 and 50g/kg FCLM was higher (P < 0.05) than for chickens subjected to a diet with 150 g/kg FCLM. During the finishing phase, TFI increased linearly (P < 0.05) with increasing inclusion level of FCLM in chicken diets, while WG decreased (P < 0.05) with inclusion level of FCLM. Treatment diets had no effect (P > 0.05) on the eating qualities of breast meat. However, juiciness was significant (P < 0.05) for the cooking method and treatment interaction. At 50 g/kg inclusion level, boiled meat had a higher (P < 0.05) juiciness score than roasted meat. Tenderness, on the other hand, was significant (P < 0.05) for the interaction of gender and treatment. Females considered the boiled meat to be more tender than the males at 150g/kg inclusion level. Using principal component analysis (PCA), a positive correlation was observed between teeth adhesion and fibrousness, flavour and juiciness, and springiness and tenderness. Conclusion: From the study, it can be concluded that FCLM can be used as an ingredient in the diets of broiler chickens. Inclusion level of 50g/kg can be used in chicken diets during the growing phase, whereas in the finishing phase, inclusion level of 150g/kg FCLM can be used. The FCLM did not affect the eating quality of breast meat.

Lactobacillus buchneri and molasses can alter the physicochemical properties of cassava leaf silage.

In developing countries where feed resources are scarce, cassava leaves can be used as feed for animals. However, the use of cassava leaves is limited mainly because of their high fibre content and overall acceptability by animals. The resolution to this problem is to process the cassava leaves by ensiling and using additives. Therefore, the objective of the study was to determine the effects of including different inclusion levels of molasses and bacteria concentration on the physicochemical properties of cassava leaf silage. Molasses was added at inclusion levels of 0, 3, 5 and 7 g/100g of the chopped cassava leaves, and Lactobacillus buchneri was mixed with chopped cassava leaves at different concentrations of 0, 3.1 × 106 cfu/ml, 3.1 × 108 cfu/ml and 3.1 × 1010 cfu/ml. The effects of inclusion level of molasses on the colour, smell and texture of cassava leaf silage were significant (P < 0.05). Inclusion of bacteria concentration also influenced the smell of silage (P < 0.05). Effects of the inclusion level of molasses and bacteria concentration resulted in decreased pH, crude protein and crude fibre of silage (P < 0.05). There was a quadratic relationship between Ca and K with inclusion level of molasses in cassava leaf silage (P < 0.05). A positive linear relationship was observed between Mg and molasses inclusion levels in cassava leaf silage (P < 0.05). Using principal component analysis (PCA), molasses had a strong positive correlation with PCA 1, whereas crude fibre, pH and crude protein had a positive correlation with PCA 2. The inclusion level of bacterial concentration was negatively correlated to Ca, CP, P and CF. From the study, the use of molasses and L. buchneri can greatly improve the physicochemical qualities of cassava leaf silage.

A review of limitations to using cassava meal in poultry diets and the potential role of exogenous microbial enzymes.

Cassava (Manihot esculenta), a crop grown in the tropics, is increasingly becoming a vital feed resource for human beings and livestock. Traditionally, cassava has been used primarily as a source of food for humans. However, it is becoming an increasingly important ingredient in livestock feed. The use of cassava leaves and roots in poultry diets is limited because of nutrient imbalances and toxins (hydrogen cyanide (HCN)) found in them. High HCN is reduced to innocuous levels by processing the ingredient using a simple sun drying method. Plant fibre content can be reduced and made available for use by poultry through the use of exogenous enzymes. More recent innovative interventions in biotechnology have brought about various exogenous enzymes that can help improve the digestibility of fibrous diets. These include, among others, carbohydrases, proteases and phytases. The extent to which the animals utilise nutrients is influenced by the type of enzyme and the physicochemical properties of the feed ingredient. This review aims to collate information on the current state of knowledge on the use of exogenous microbial enzymes in diets containing cassava and how the enzymes that target carbohydrates might be useful in making nutrient available for poultry.

Ochratoxin A: Carryover from animal feed into livestock and the mitigation strategies.

This review aims to highlight the effects of ochratoxin A (OTA) in the feed of meat-producing animals. The accumulation of OTA in feed and its distribution in various farm animals were compared and evaluated. Primarily, the oral administration of OTA-contaminated feed and the predisposition in an animal's vital organ were critically examined in this work. The collated reports show that OTA directly associated with endemic nephropathy and its high concentration leads to degeneration of liver cells, and necrosis of intestinal and lymphoid tissues. At present, limited reports are available in the recent literature on the problems and consequences of OTA in feed. Therefore, this review focused on the OTA carryover from feed to farm animals and the interaction of its secondary metabolites on their biochemical parameters. Hence, this report provides greater insights into animal health related to OTA residues in meat and meat products. This article also explores mitigation strategies that can be used to prevent the carryover effects of OTA in livestock feeds and the effects in the food chain.

Acceptability, growth performance and nutritional status of chickens fed cassava leaf meal (CLM)-based diets.

This study evaluated the effect of feeding cassava leaf meal-based diets on feeding behavioural patterns, growth performance parameters and nutritional status of chickens. A total of 200 Cobb-500 female chickens (initial weight 0.53 ± 0.098 kg) were used in the experiment. The chickens were subjected to treatment diets with cassava leaf meal (CLM) included in diets at 0, 100, 200 and 300 g/kg. Number of visits to the feeder/drinker, duration of each visit on the feeder/drinker, average daily feed intake (ADFI), average daily gain (ADG) and feed efficiency (gain:feed ratio), total protein (TP), albumin, globulin and creatine kinase (CK) were the response variables that were measured of interest. Effects of inclusion level of CLM in diets of chickens on number of visits to the feeder and drinker was significant (P < 0.05). Duration of each visit on the feeder increased (P < 0.05) with inclusion level of CLM in diets of chickens. Conversely, time spent by chickens on the drinker decreased with inclusion level of CLM in diets (P < 0.05). Average daily gain and G:F decreased linearly (P < 0.05) with inclusion level of CLM in diets of chickens. Albumin, globulin and total protein in blood of chickens increased linearly (P < 0.05) with inclusion level of CLM in diets of chickens. From the study, it can be concluded that acceptability of diets with inclusion of CLM during the growing-finishing phase of the chickens was not affected. However, weight gain was compromised at higher inclusion levels of CLM in diets of chickens.

Impact of climate change on sustainable livestock production and existence of wildlife and marine species in the South Pacific island countries: a review.

Climate change poses a significant threat to humanity by intensifying multiple hazards. South Pacific Island countries (SPICs) are affected and face a dire challenge to survival. Sea level rise is reducing the already limited land for human and animal habitation. Tropical cyclones and droughts are having devastating effects on the lives of humans and animals. Tropical cyclone Winston, for example, destroyed infrastructure for humans and animals in some parts of Fiji, and infectious diseases are spreading to regions where they are not commonly seen following cyclones and floods. Likewise, climate change is making droughts worse. Droughts are destroying crops and pasturelands and making freshwater unavailable for human and animal populations in the Solomon Islands and Tuvalu. There is an urgent need to ascertain the best approaches to tackle the events, which are already happening. Short-term changes can be managed at local levels through public awareness campaigns, understanding the weather patterns to prepare for disasters, reclaiming land, improving livestock breeds, introducing zoos and wildlife sanctuaries and inventing economically feasible technologies to harvest water. Long-term solutions depend on the implementation of international agreements, international aid and collective effort.

Potential of ethno-veterinary medicine in animal health care practices in the South Pacific Island countries: a review.

The South Pacific island countries (SPIC) are among the most vulnerable countries in the world to economic shocks, climate change and natural disasters. Agriculture including livestock production makes important contribution to socio-economic development in the region. However, the livestock sector is marred by many livestock diseases, which are crippling the economies as well as threatening the food security of the island nations, most of which have high dependence on imports. Limited veterinary medical facilities, high cost of conventional medicine and remoteness of some rural farming communities make it difficult for farmers to treat their diseased animals. Nevertheless, the island nations are endowed with vast reserves of medicinal plants in diverse ecosystems including mangroves, rainforests and tropical dry forests. Despite the ubiquity of traditional medicine systems, most of the plant species have been used to treat human aliments in the SPIC and very few farmers utilise herbal medicine to treat their animals. This review highlights the common diseases affecting livestock production in the SPIC, threats to ethno-veterinary knowledge, and potential plant species and their efficacies to treat animal diseases and parasites. It also discusses the common methods of preparation of veterinary herbal medicine and possible ways of making the medicine available in the formal and informal markets in the region. It is envisaged that the review will stimulate further ethno-veterinary research among livestock disease management practices in the SPIC.

Browse silage as potential feed for captive wild ungulates in southern Africa: A review.

The objective of the review was to assess the potential of indigenous browse trees as sustainable feed supplement in the form of silage for captive wild ungulates. Several attempts to use silage as feed in zoos in temperate regions have been conducted with success. Information on silage from the indigenous browse trees preferred by wild ungulates in southern Africa is scanty. The use of silage from the browse trees is of interest as it has potential to reduce or replace expensive feed sources (pellets, fruits and farm produce) currently offered in southern African zoos, game farms and reserves, especially during the cold-dry season. Considerable leaf biomass from the indigenous browse trees can be produced for silage making. High nutrient content and minerals from indigenous browsable trees are highly recognised. Indigenous browse trees have low water-soluble carbohydrates (WSC) that render them undesirable for fermentation. Techniques such as wilting browse leaves, mixing cereal crops with browse leaves, and use of additives such as urea and enzymes have been studied extensively to increase WSC of silage from the indigenous browse trees. Anti-nutritional factors from the indigenous browse preferred by the wild ungulates have also been studied extensively. Indigenous browse silages are a potential feed resource for the captive wild ungulates. If the browse trees are used to make silage, they are likely to improve performance of wild ungulates in captivity, especially during the cold-dry season when browse is scarce. Research is needed to assess the feasibility of sustainable production and the effective use of silage from indigenous browse trees in southern Africa. Improving intake and nutrient utilisation and reducing the concentrations of anti-nutritional compounds in silage from the indigenous browse trees of southern Africa should be the focus for animal nutrition research that need further investigation.

Growth performance, economic benefits and sensory characteristics of meat from broilers finished on Acacia anguistissima leaf meal-based diets.

The objective of the study was to determine growth performance, viscera organ development, economic benefit and sensory characteristics of meat from broilers finished on Acacia anguistissima leaf meal-based diets. One hundred and eighty Cobb 500-day-old chicks were used in the study. Acacia anguistissima was used as a protein source and included in broiler diets at 0, 50 and 100 g/kg. Total feed intake (TFI), average daily gain (ADG), and gain to feed ratio (G:F) and cost benefit analysis were determined. There were no differences in TFI of broilers across treatments diets. Average daily gain and gain to feed (G:F) ratio were low (P < 0.05) for broilers feeding on diet with100 g/kg acacia meal. Highest returns from weight gain were obtained from broiler chickens fed on diet with 50 g/kg inclusion level of A. anguistissima (P < 0.05). Intestinal length increased with inclusion level of A. anguistissima whereas liver and spleen weight decreased with inclusion level of A. anguistissima (P < 0.05). Female consumers gave higher scores for overall flavour intensity than male consumers (P < 0.05). Treatment diets influenced consumer sensory characteristics of broiler meat (P < 0.05). High sensory scores were observed for overall flavour intensity (OFI) for both boiled and deep fried meat from broilers fed 100 g/kg A. anguistissima. It can be concluded that A. anguistissima meal can be used effectively up to 50 g/kg in broiler diets without compromising performance of chickens and can influence a few sensory characteristics.

Growth performance of broilers fed on sprouted-roasted guar bean (Cyamopsis tetragonoloba) based diets.

In a completely randomized block design with 96 Cobb-500 broilers, a study was conducted to evaluate the potential of dietary inclusion of sprouted then roasted guar bean in broiler diets. The 96 male day-old broiler chicks, blocked by pen into equal weight groups of six chicks replicated four times per treatment, were randomly allocated to treatment diets containing graded levels of sprouted then roasted guar bean meal (GBM) at 0, 50, 100 and 150 g kg-1 inclusion level. The guar bean was sprouted and roasted to reduce guar gum effect. Total feed intake decreased significantly as the guar bean meal content increased in the starter phase (P < 0.05), but no significant differences in intake of the finisher phase (P > 0.05) were observed. Diets containing 0 and 50 g kg-1 GBM recorded significantly higher total feed intake compared to the diet containing 150 g kg-1 GBM. Although average weight gain was not significantly different in birds fed 0 and 50 g kg-1 GBM diets, it was significantly higher than in birds fed on 100 and 150 g kg-1 GBM diets. Feed conversion ratio was not significantly different among treatment groups (P > 0.05) but showed a general decreasing trend with increasing guar bean meal inclusion level, the effect being more pronounced during the starter phase. In conclusion, the optimum inclusion level of sprouted then roasted guar bean meal in broiler diets is 50 g kg-1.

Effects of different dietary inclusion levels of macadamia oil cake on growth performance and carcass characteristics in South African mutton merino lambs.

Growth performance and carcass characteristics of South African mutton merino fed graded levels of macadamia oil cake were assessed. A total of 60 South African mutton merino lambs were used in the experiment (initial live weight 25.0 ± 0.45 kg). Five diets with different inclusion levels of macadamia oil cake (MOC) were formulated: T1 (0% MOC, control), T2 (5% MOC), T3 (10% MOC), T4 (15% MOC) and T5 (20% MOC). Effects of inclusion level of MOC on average daily gain (ADG) and average daily feed intake (ADFI) were not significant (P > 0.05). Effects of inclusion levels of MOC on feed conversion ratio (FCR) of sheep were significant (P < 0.05). Highest proportion (71.2%) of sheep in the study had a carcass fat classification of 2, followed by a proportion of 17.3% sheep with a carcass fat classification of 3 and lastly 11.5% sheep had carcass fat classification of 4. Warm and cold carcass mass, chest circumference, carcass length and dressing percentage were higher in sheep fed on 5% MOC compared to other treatment diets (0, 10, 15 and 20% MOC) (P < 0.05). Fat rib eye had a greater area in sheep fed on 5% MOC (P < 0.05). It was concluded that 5% MOC provided the best results in terms of carcass characteristic measurements in sheep.

The potential of replacing soyabean oil cake with macadamia oil cake in broiler diets.

A study was conducted to evaluate the potential of macadamia oil cake (MOC) as a replacement of soyabean oil cake (SOC) in Ross broiler diets. The 600 1-day-old male broiler chicks were randomly blocked into 30 equal-weight groups of 20 chicks. For each growth phase, basal and summit diets were blended in various proportions (100 % SOC and 0 % MOC, 75 % SOC and 25 % MOC, 50 % SOC and 50 % MOC, 25 % SOC and 75 % MOC, and 0 % SOC and 100 % MOC) to form five treatments. The diet with 100 % MOC had the least feed intake, final body weight and weight gain compared to other diets (P < 0.05). The increased abdominal fat of broilers fed more than 50 % levels of MOC could be due to high levels of lipids in MOC compared to soyabean oil cake. The feed conversion ratio did not differ significantly for most of the treatments (P > 0.05). It was concluded that the threshold of 25 % MOC can replace soybean oil cake meal in the diets of broiler provided that this alternative feed ingredient is readily available at an affordable cost.