Animal Production Science
Volume 62 Number 7 2022
AN20214Cassava wastewater can be safely used in the diet of feedlot lambs
In ruminant supplementation, the main energy source used is maize; however, this product is a commodity that is influenced by the international market, and this often makes its use in animal feed unfeasible. To solve this problem, the use of agribusiness residues has been proposed in terms of animal nutrition, without causing significant changes in the nutritional value of diets. Depending on the quantity, cassava wastewater can be safely used in the ration of feedlot lambs.
Relationships have previously been identified between reticulo-rumen volumes, measured using computed tomography (CT) scanning of sheep, and methane emissions. This study investigated reticulo-rumen volumes, measured from CT images of live lambs, and found variation between breeds, sires and individual animals that could be exploited for genetic selection. Genetic relationships of reticulo-rumen volume with other economically and environmentally important traits, including methane emissions, should be fully investigated to inform potential use of this measurement in breeding programmes to reduce methane emissions.
AN21576Increasing the proportion of Leucaena leucocephala in hay-fed beef steers reduces methane yield
Australia has a goal to make red meat production carbon neutral by 2030, and reducing enteric methane emissions from ruminants is an important step. Leucaena, a tropical legume shrub, was shown to reduce methane yield by up to 20% in hay-fed cattle given increasing levels of leucaena from 0% to 48% of the diet. An increase in methane yield when polyethylene glycol was added to the diet suggested that tannins may be reducing rumen methanogenesis.
AN21576 Abstract | AN21576 Full Text | AN21576PDF (707 KB) | AN21576Supplementary Material (433 KB) Open Access Article
Forage silage is commonly used in dairy farming but inappropriate ensiling could be associated with occurrence of mycotoxins as well as low quality silage. Five of 23 mycotoxins screened were identified and quantified from different types of silage and from upper, central and lower parts of the silos, drawing attention to possible occurrence in cow milk. The silages were generally of low quality, with high pH and dry matter content.
AN21437Optimum inclusion rate of barley in diets of meat chickens: an incremental and practical program
Barley is an alternative grain to wheat in Australian meat chicken diets, and often cheaper. However, the presence of some anti-nutritional factors in barley means that the grain is used at limited levels in the diet. Our results indicate that an incremental program is an effective approach to optimise barley inclusion rate in meat chicken diets, to formulate more cost-effective finished feeds and add value to Australian barley, particularly when export markets become precarious.
AN21437 Abstract | AN21437 Full Text | AN21437PDF (1.8 MB) Open Access Article
The consumption of pork is increasing and presents an opportunity for pig farmers to make more profits. This study revealed that the high cost of commercial feeds can be overcome by feeding a low-cost diet containing 22% brewers’ spent grain, 15% yeast and 60% malt dust. By lowering the cost of quality feeds, pig productivity, population and profits will increase.
It is important to identify efficient cows. However, there is no standard measure for cow–calf efficiency. Cow weight and Large Stock Units were used to identify cow–calf efficiency, either as a ratio with calf weaning weight or as covariates. The use of ratios favoured the smaller cows. This inconsistent definition of cow–calf efficiency makes its improvement challenging. The difference between output and input can be maximised, when traits are reported in consistent units like joules, or the carbon footprint.
AN21595Utilising Gliricidia sepium leaf meal as a protein substitute in cassava-based supplements to increase average daily gain of Ongole bulls and income of smallholder farmers
Formulating cattle rations in smallholder enterprises to include locally available forages provides an opportunity to increase beef cattle productivity with a resultant increase in farmer profitability. The evaluation of supplementing locally available cassava and Gliriicidia sepium leaf meal and traditional supplements into village enterprises demonstrated that all supplementation increased liveweight gain and profitability. Feeding formulated rations using local ingredients is an important strategy to markedly increase profitability and to increase meat production globally.
AN21595 Abstract | AN21595 Full Text | AN21595PDF (727 KB) Open Access Article
AN20301Effects of silage to concentrate ratio and duration of feeding on the fatty acid composition of ovine muscle and adipose tissue
The fatty acid profile of meat from lambs fed a pasture diet is affected by changing the diet before slaughter. The effect of pasture on meat fatty acids is partially conserved by feeding lambs on grass silage for up to 72 days, or cereal-containing diets for less than 36 days, before slaughter. Feeding cereal-containing diets to lambs for more than 54 days results in a meat fatty acid profile that reflects the composition of the cereal-containing diet.
AN20301 Abstract | AN20301 Full Text | AN20301PDF (998 KB) | AN20301Supplementary Material (316 KB) Open Access Article
AN19648Partial replacement of sugarcane with cactus (Opuntia stricta) cladodes improves milk yield and composition in Holstein dairy cows
Including sugarcane in dairy cow diets usually decreases feed intake; therefore, large proportions of concentrate are often needed to meet the nutrient requirement. We evaluated the effects of partial replacement of sugarcane with cactus (Opuntia stricta [Haw.] Haw) cladodes. Although an optimum response for most variables was achieved when cactus cladodes replaced ∼1/3 of sugarcane, the highest level of replacement (51%) also resulted in a better overall performance than that observed for a diet containing only sugarcane as a forage source.