Helianthus annuus

Sunflower

Useful reference: 451

Annual or perennial plant up to 6 m high with heads up to 3 dm in diameter. The seeds of the cultivated sunflower species are used as poultry feed or in the manufacture of oil and its by-product, sunflowerseed meal. Undecorticated and decorticated cakes are made. Sunflowerseed oil meal - equivalent in nutrient value to solvent- extracted soybean oil meal - can be produced by lowering the processing temperatures to 93 C in the cooker and 104 C in the conditioner and by opening the choke of the expeller. The seed consists of between 25% and 40% shell. Even if the seeds are decorticated before processing, about one third of the removed shells are usually added back to the decorticated kernels to increase the efficiency of extraction.

SEED. Despite the high percentage of fibre in sunflowerseeds, they can be fed to laying hens in place of a cereal grain. On account of its fat content, the seed has a high energy value. The oil is said to be particularly beneficial during the winter and when the birds are moulting. Sunflowerseed has the highest sulphur amino-acid content of the major oilseeds.

OIL MEAL. The composition of the oil meal varies with the quality of the original seed and the method of processing. A wide variety of products are available on the market, ranging from low-quality strawlike meals to high-quality flours. The use of high-fibre sunflowerseed oilcakes is restricted to the feeding of adult ruminants, whereas the decorticated cake is a digestible high-protein feed that can be used freely in balanced mixtures for all livestock. As the cakes are hard, they are best fed ground and incorporated in compounds. Meals with a high fat content tend to produce soft pork if fed in large amounts. If limited to about one third of the protein supplement, the meal gives good results in pigs, especially those weighing over 45 kg. The oilcake does not keep well. Supplementary lysine will be necessary if large amounts are to be fed to nonruminants, and for poultry a rich source of energy has to be added.

DESEEDED HEADS. When the deseeded heads have a high moisture content, they may be silaged with or without molasses. Very dry heads can be made into a feed meal. The heads must first be shredded and then well dried, preferably in a grass drier, before being reduced to meal in a hammer-mill.

HULLS. Sunflower hulls can be used as a roughage for ruminants. Lambs have been fed 0.5 kg of pelleted hulls daily with good results.

					As % of dry matter
				DM	CP	CF	Ash	EE	NFE	Ca	P	Ref
Heads with seeds,
mature, South
Africa					12.7	23.9	9.3	13.7	40.4	0.63	0.08	489
Seeds with hulls,
Chile				93.7	12.3	27.9	3.1	42.0	14.7	0.21	0.59	315
Oilcake without
hulls, mechanically
extracted, Uganda				91.0	34.1	13.2	6.6	14.3	31.8	0.30	1.30	69
Oil meal with hulls,
solvent extracted,
Zimbabwe				91.3	26.7	37.8	5.7	4.6	25.2			499
Oil meal without
hulls, solvent ex-
tracted, average
values				90.0	42.7	16.1	7.7	4.0	29.5			289
Heads without
seeds, Zimbabwe				88.3	10.1	20.6	13.1	3.6	52.6			227
Hulls, USA				89.9	20.0	32.1	4.9	6.8	36.2			247
							Digestibility (%)
					Animal		CP	CF	EE	NFE	ME	Ref
Whole heads					Sheep		72.2	55.2	93.2	72.9	2.93	489
Seeds with hulls					Sheep		90.1	33.5	95.0	71.0	4.28	512
Cake without hulls,
mechanically extracted					Sheep		75.0	26.0	90.0	54.0	2.85	365
					Nylon bag degradability
						a	b	c		12hr	48hr	Ref
						(%)	(%)	(/hour)		(%)	(%)
Sunflower, Portugal					DM	32.0	44.0	0.1229			75.6	627
	[P (rumen degradability at time t) = a+b*(1-exp(-c*t))]
		Amino acid composition as % of crude protein
Seed											Ref	40
Arg	Cys	Gly	His	Ils	Leu	Lys	Met	Phe	Thr	Try	Tyr	Val
10.0	1.7	5.6	2.3	4.1	5.5	3.6	1.5	4.6	3.4	-	1.6	4.0
Oilcake											Ref	119
Arg	Cys	Gly	His	Ils	Leu	Lys	Met	Phe	Thr	Try	Tyr	Val
9.1	1.8	5.6	2.8	4.2	6.9	3.5	2.2	5.1	3.4	1.4	2.9	5.8