Support Feedipedia

Automatic translation

Who is visiting Feedipedia?

 

Editor area

Sweet potato (Ipomoea batatas) forage

Description and recommendations

Common names

Sweet potato, patate douce, batata da terra, batata doce

Product names: sweet potato vines, sweet potato foliage, sweet potato leaves, sweet potato leaf meal, sweet potato vine meal

Synonyms

Convolvulus batatas L., Ipomoea apiculata M. Martens & Galeotti

Description

Sweet potato (Ipomoea batatas (L.) Lam.) is a tuberous-rooted perennial mainly grown as an annual. The roots are adventitious, mostly located within the top 25 cm of the soil. Some of the roots produce elongated starchy tubers. Tuber flesh colours can be white, yellow, orange and purple while skin colour can be red, purple, brown or white. The stems are creeping slender vines, up to 4 m long. The leaves are green or purplish, cordate, palmately veined, borne on long petioles. Sweey potato flowers are white or pale violet, axillary, sympetalous, solitary or in cymes. The fruits are round, 1-4 seeded pods. The seeds are flattened (Ecocrop, 2010; Duke, 1983).

Sweet potato is cultivated for food in more than 100 countries. The area under cultivation was 8.5 million ha in 2009 and the worldwide tuber yield was 12648 kg/ha (FAO, 2010). The main sweet potato producers are China, Indonesia, Vietnam, India, Philippines and Japan in Asia, Brazil and the USA in the Americas and Nigeria, Uganda, Tanzania, Rwanda, Burundi, Madagascar, Angola and Mozambique in Africa (FAO, 2010).

Sweet potato tubers and leafy tops are mainly used as food (Duke, 1983). Sweet potato green parts are also a very valuable feed for livestock: vines and foliage can be dried and fed to cattle: they compare favourably with alfalfa hay (Duke, 1983). The tubers are relished by pigs and cattle and sweet potato tubers processing by-products can be fed to livestock (see the Sweet potato tubers datasheet).

Sweet potato vines and foliage can be fed to cattle, sheep, goats, pigs, rabbits and goats. Sweet potato forage can be an emergency supply of cattle feed in periods of water stress (drought or dry seasons) (Scott, 1992). It may be fed fresh, dried or ensiled, and makes make a very palatable silage with a pleasant fruity smell (Lebot, 2009). Sweet potato forage can also be dried, ground and mixed with sugarcane by-products.

For optimal leaf and stem production it is advisable to cut at intervals of 20 days with a defoliation of 50% of the total stems, since greater defoliation could reduce root production. Vines and leaves can be harvested three or four times per growing season (Lebot, 2009).

Distribution

The center of origin of the sweet potato is thought to be located between the Yucatán Peninsula of Mexico and the mouth of the Orinoco River, in Venezuela. Sweet potatoes as old as 8000 years have been found in Peru. It has then spread to the Caribbean and Polynesia. It is now widely cultivated between 40°N and 32°S, up to 2000 m (and up to 2800 m in equatorial regions) (Ecocrop, 2010; Paneque Ramirez, 1992).

Sweet potatoes are cultivated wherever there is sufficient water to support their growth: optimal annual rainfalls for growth range between 750-2000 mm. When rainfall level is below 850 mm irrigation may be necessary but it should be stopped before harvest in order to prevent the tubers from rotting. Sweet potato is a warm-season annual, requiring 20-25°C average temperatures and full sunlight for optimal development. It needs a frost-free period of 110-170 days and growth may be hampered below 20°C average day temperatures. Sweet potato thrives in well-drained loamy soils with high humus content that provides warm and moist environment to the roots. Optimal soil pH is between 5 and 7 (Ecocrop, 2010; Ecoport, 2010; Paneque Ramirez, 1992).

Sweet potato is mildly drought-tolerant and can survive dry spells during the summer. However, low humidity impairs crop quality even if the plant resume growth after a water stress (Ecoport, 2010; Paneque Ramirez, 1992).

Processes

Huge amounts of sweet potato foliage are produced during tuber harvesting and the vines decay in 2 or 3 days. When animals cannot consume the forage in such a short time, it may be interesting to dry or ensile it using low-cost methods (Renaudeau, 2010, personal communication).

Silage

Sweet potato leaves and vines can be preserved by ensiling (Nguyen Thi Tinh et al., 2006; Lebot, 2009). After harvest, green and healthy material is chopped to 0.2-0.5 cm length and carefully prewilted during 1-4 h in the sun so that moisture content is reduced by 40-45%. The prewilted material is then thoroughly mixed with 10% rice bran, corn meal or cassava or sweet potato root meal and 0.5% salt. After mixture, the material is put in impermeable plastic bags, heavily pressed to remove the air from the mixture and the bags are carefully tight and dated (Nguyen Thi Tinh et al., 2006).

Sweet potato vines can be fermented with chicken manure: it results in higher crude protein, DM and ash contents than the other silages. Ensiling provides a good sanitary that does not contain aflatoxins, Salmonella, and Escherichia coli (Lebot, 2009).

Environmental impact

Sweet potato is remarkably adapted to scarce conditions since it thrives even with very low inputs and minimal horticultural practices. It grows very quickly, has some tolerance of drought and provides high amounts of nutrients during the scarcer periods (Scott, 1992).

Potential constraints

The vines contain trypsin inhibitors but at relatively harmless levels.

Nutritional attributes

Sweet potato forage is mainly a source of protein and contains about 15-30% DM of crude protein but the forage quality depends on the proportion of leaves and stems, the latter containing much less protein than the leaves. Lysine is the main limiting amino acid (Le Van An, 2004). Unlike legume forages, it does not contain notable quantities of antinutritional factors.

Ruminants

The vines are separated from the roots after harvest and provide a nutritive and relished green feed for ruminants (Nguyen Thi Tinh et al., 2006). It is a suitable protein supplement for animals receiving low quality forage.

Digestibility and degradability

Dry matter digestibility was found to be 70% (Ffoulkes et al., 1978a) and dry matter degradability was in the 40-50% range (Etela et al., 2008a). Protein degradability of fresh sweet potato forage was found to be quite high (about 70%), but the undegradable dietary protein was lower than that of protein supplements of similar degradability (cottonseed meal and Gliricidia sepium) so that less digestible true protein is available to the animal for metabolism after digestion and absorption (Kabi et al., 2005).

Dairy cows

A cow of 400-500 kg can consume 50-70 kg daily (Göhl, 1982). Sweet potato forage can be fed to dairy cows as a supplement to forages such as Guinea grass (Megathyrsus maximus) or sorghum silage (Etela et al., 2009; Etela et al., 2008b; Ashiono et al., 2006). Such supplementation results in lower DM intake, but higher ME utilization for milk production (Etela et al., 2009; Etela et al., 2008b). While it has no negative effect on milk quality, it can only sustain low levels of milk production and does not compare favourably with dried brewers' grains or cassava forage as a supplement for milk production, though it could help saving production costs for smallholders (Etela et al., 2009; Etela et al., 2008b; Lopez et al., 1998).

Sweet potato vines can efficiently supplement sorghum silage in dairy cows diet and they have great potential for improving milk yield at up to 70% inclusion (Ashiono et al., 2006; Göhl, 1982).

Growing and fattening cattle

Heifers

Heifers fed on Napier grass (Pennisetum purpureum) and supplemented with sweet potato forage have lower DM intake than heifers fed on grass alone. Growth performance (500 g daily weight gain) is similar on grass and grass + sweet potato and lower than on grass+alfalfa (Kariuki et al., 1998)

Bulls

In Zebu bulls, supplementation with sweet potato forage of a diet based on sugarcane stalks increased voluntary intake and live weight gain, which was explained by the protein in the sweet potato forage acting as a by-pass nutrient and by the physical nature of this forage improving the rumen function (Ffoulkes et al., 1978a). Addition of N urea in association with sweet potato forage supplementation resulted in further live weight gains. This was was possibly due to the improvement in the rumen ecosystem which may encourage microbial growth and create a demand for fermentable N (Meyreles et al., 1979).

Calves

Sweet potato vines were found to be a high quality feed for calves due to their high yield, palatability and crude protein content. When offered ad libitum to calves fed Napier grass, they did not significantly affect the average daily gains of calves, and up to half of the milk can be saved when sweet potato vines are fed as a milk replacer (Orodho et al., 1996). Calves fed on Napier grass and sweet potato forage alone did better than those fed on Napier alone, but less that those fed on Napier grass supplemented with mixtures of sweet potato vines and other legume forages such as alfalfa, desmodium, Leucaena leucocephala and Sesbania sesban (Lanyasunya et al., 2006).

Sheep

The carrying capacity of sweet potato plots pruned for sheep feeding was comprised between 100 and 165 heads/ha and an interval of 6 weeks may be adopted to optimize yield and quality of the forage (Olorunnisomo, 2007a). Mixing sweet potato forage and roots resulted in better nutrient utilization and lower cost per kg of live weight gain was reduced. A 50:50 sun-dried mix maximized economic returns from cultivating sweet potato for sheep feeding (Olorunnisomo, 2007b). Sheep seem to prefer cassava leaves to sweet potato leaves (Haryanto et al., 1982).

Lambs grazing sweet potato leaves recorded daily weight gains around 50-60 g (Rondon et al., 1989).

Goats

Though fairly relished by goats, sweet potato vines have low CP intake, poor N retention and poor CP and DM digestibility (Katongole et al., 2009a). It compared unfavourably with cassava leaf meal or Sesbania grandiflora as it resulted in lower DM intake and lower live weight gain (Vo Lam et al., 2004). However, better results in DM intake and animal performance have been yielded when goats could get accustomed to sweet potato vines (Kebede et al., 2011). Poor animal performances (less than 15 g daily weight gain) are also recorded when sweet potato vines are used to supplement a diet of Napier grass (Pennisetum purpureum), maize bran and Leuceana leucocephala leaves (Katongole et al., 2009a). Higher animal performances (44 to 82 g daily weight gain) are obtained when sweet potato vines supplement a cottonseed cake and maize bran mixture at 1:4 ratio (Katongole et al., 2009b) or a low quality grass (Ischaemum aristatum var. indicum) (Aregheore et al., 2004), respectively. Hence, sweet potato vines provide sufficient crude protein and metabolizable energy to sustain goat meat and milk production in tropical conditions, even during scarce periods where standard feeds are lacking (Katongole et al., 2009b; Katongole et al., 2008; Nambi et al., 2001). Feeding goats with sweet potato vines provides cheap nitrogen and increases feed efficiency (Aregheore et al., 2004). Sweet potato vines could profitably replace 50% concentrate feed (78.4% wheat bran, 20.6% noug seed cake) in male goats diet (Kebede et al., 2011).

Goats seem to prefer cassava leaves to sweet potato leaves (Haryanto et al., 1982).

Pigs

Sweet potato vines are one of the most promising protein sources coming from tropical forages for pigs (Bui Huy Nhu Phuc, 2000). Thanks to its high crude protein content, high CP digestibility (above 65%) sweet potato foliage in fresh, dried or ensiled form can be used as a valuable protein and amino acids source in low fibre pigs diets in tropical areas (Le Van An et al., 2004; Rodriguez et al., 2003; Barrios et al., 2002).

In small-scale pig farms, sweet potato foliage could replace up to half the protein normally provided through conventional feedstuffs such as soybean meal or fishmeal (Preston, 2006). Sweet potato foliage can be fed to pigs without any negative effects on health (Renaudeau, personal communication). In Vietnam, sweet potato foliage is much appreciated by the poorest pig farmers because it can be fed year-round and its use results in lower production costs and higher net income (Ngo Huu Toan et al., 2007). In Cuba, sweet potato crop, including roots as energy source and vines as a protein source, can compete with maize in pig feed in Cuban pig production (Dominguez, 1992).

Fresh sweet potato vines

Growing and fattening pigs

Fresh sweet potato vines can be profitably included in growing and finishing pigs diets as they enhance basal diet palatability, overall DM intake, nutrient digestibility and animal performances (Chiv Phiny et al., 2010; Chhay Ty et al., 2007; Nedunzhiyan et al., 2000). They are generally offered ad libitum (Chiv Phiny et al., 2010; Chhay Ty et al., 2007). Fresh sweet potato foliage palatability is rather high and compares favourably with other tropical foliages such as mulberry leaves (Régnier et al., 2010 (unpublished); Chiv Phiny et al., 2010). The average daily fresh sweet potato foliage intake is about 3 kg/d (500 g DM/d) for a 50 kg pig, and 750 g/d for fresh chopped vines (Régnier et al., 2010 (unpublished); Nedunzhiyan et al., 2000).

Fresh sweet potato vines can be used as the sole protein supplement, combined with other foliage such as mulberry leaves or cassava leaves or associated to a protein-rich (20-23%) supplement (Chiv Phiny et al., 2010; Chhay Ty et al., 2007; Gonzalez et al., 2003). However, they appear to have a lower nutritive value than cassava leaves, stylo (Stylosanthes guianensis) and duckweed (Du Thanh Hang et al., 2009)

Sweet potato fresh foliage offered to weaned piglets can substitute 10 % of the cereal concentrate with satisfactory animal performance (weight gain, feed conversion, mortality and herd culling) (Göhl, 1982). However, because of its bulkiness, fresh sweet potato foliage cannot be included in large amounts in the diets of young pigs (Renaudeau, personal communication).

Fresh foliage replacing 25 and 50 % of soybean meal in a sweet potatoes and soybean meal diet resulted in a decreased of dry matter intake that was probably due to its bulkiness, but the feed conversion ratio was conserved at the 25% replacement level (Göhl, 1982).

Gilts and sows

Sweet potato leaves inclusion can be as high as 50% in the diets of gilts or pregnant sows, and up to 20% for lactating sows. They can also replace up to 50% soybean meal during pregnancy and lactation (Hoang Nghia Duyet et al., 2010; Hoang Nghia Duyet, 2003).

Preserved sweet potato foliage

Sweet potato foliage in fresh, dried or silage is a valuable ingredient for pig diets. Though dried and ensiled sweet potato foliage have slightly lower lysine digestibility, the three products have similar palatability and overall nutritive values (Le Van An et al., 2004).

Many types of silages can be done with sweet potato foliage: sweet potato silage can be prepared with leaves alone or in mixtures: leaves and lysine, sweet potato leaves and cassava leaves, sweet potato leaves and sweet potato roots (Nguyen Thi Hoa Ly et al., 2010; Le Van An et al., 2005). Ensiled cassava leaves and sweet potato vine can replace more than 70% of the protein from fish meal (or 35% of total diet CP), reducing feed costs without deleterious effects on growing pig performances or carcass quality. (Nguyen Thi Hoa Ly et al., 2010). 30% inclusion rate for ensiled sweet potato foliage should not significantly affect growth performance in growing pigs (Le Van An et al., 2005). Higher inclusion rates (40 and 60% DM) would reduce growth by 16 and 30%, respectively (Hoang Huong Giang et al., 2004).

In post-weaning diets, sweet potato inclusion (meal or silage) should not exceed 10% and to 30-40 % inclusion is advisable in growing-finishing diets (Mora et al., 1992 cited by Le Van An et al., 2005).

Poultry

Dried foliage

Dried sweet potato vines can be used in poultry rations as a source of protein and carotenoids, particularly beta-caroten and xanthophylls, and have been included in diets to enhance the yellow pigmentation of broiler skins and egg yolks. Early-harvested vines were as efficient as alfalfa meal at colouring yolks. Late-harvested vines were less efficient at colouring broiler skin (Woolfe, 1992). An optimum level of 10% has been suggested, as higher levels resulted in decrease of dry matter intake and body weight gain (Berhan Tamir et al., 2010) and levels of 20-30% reduced the feed conversion efficiency (Kagya-Agyemang et al., 2008). However, dried vines included at up to 16% in broiler diets have been shown to be as efficient as alfalfa meal for growth rate, food intake or food efficiency (Farrell et al., 2000) and 15% could be economically feasible if birds are sold if birds are sold on eviscerated carcass weight basis rather than live weight (Wude Tsega et al., 2009).

Fresh foliage

Fresh sweet potato leaves given to chickens gave the smallest animals, the highest mortality and the lowest economic results when compared to fresh leaves ofcentro (Centrosema molle) and leucaena (Leucaena leucocephala) (Dingayan et al., 1950).

Rabbits

Sweet potato vines are palatable to rabbits and have been found to be more palatable that Leucaena leucocephala and other legume trees (Raharjo et al., 1985). In rabbits fed a concentrate diet, fresh sweet potato vines resulted in a slightly lower intake and daily gain (21.1 g/day) than water spinach (Ipomoea aquatica). The best performances were obtained when adding Guinea grass (Megathyrsus maximus) to sweet potato vines, water spinash or a mixture of both forages, though the digestibility of the diets was lower (Doan Thi Gang et al., 2006). Groundnut haulms and soybean forage were more cost effective than sweet potato forage for feeding rabbits (Iyeghe-Erakpotobo, 2007).

Fish

Sweet potato leaves have been used to feed Tilapia in Ugandan fish ponds (Mwanga et al., 1988). In Vietnam, sweet potato crop residues and other macrophytes have been tested successfully for feeding Tilapia, common carps (Cyprinus carpio), giant gouramis (Osphronemus goramy) and kissing gouramis (Helostoma temminckii) (Lam My Lan et al., 2007). Sweet potato leaves were assessed to be suitable for small scale freshwater fish feeding (carps and Tilapia) due to their relatively high protein content and reduced antinutritional factors (Dongmeza et al., 2009).

Crustaceans

Crayfish

When farmed crayfish (Procambarus clarkii) were fed vines and root trimmings from a sweet potato cannery as a supplement, dried sweet potato foliage fed ad libitum daily resulted in the highest weights and longest lengths of mature crayfish, followed by sweet potato trimmings, rice stubble and rye hay. Sweet potato vines and trimmings could be fed directly to crayfish or after a very short compost period. Fresh sweet potato forage was more efficient than forage stored in water, which may be due to unpalatable decomposition products (Goyert et al., 1977).

Citation

Heuzé V., Tran G., Hassoun P., 2013. Sweet potato (Ipomoea batatas) forage. Feedipedia.org. A programme by INRA, CIRAD, AFZ and FAO. http://www.feedipedia.org/node/551 Last updated on August 10, 2013, 14:55

Tables

Tables of chemical composition and nutritional value

Main analysis Unit Avg SD Min Max Nb
Dry matter % as fed 13.0 2.9 8.5 17.6 21
Crude protein % DM 16.5 4.6 8.2 24.2 23
Crude fibre % DM 21.1 5.3 11.9 30.3 17
NDF % DM 42.7 6.7 29.8 51.6 10
ADF % DM 31.7 6.8 19.9 40.6 10
Lignin % DM 8.3 2.2 4.5 11.8 10
Ether extract % DM 4.8 2.0 2.5 10.4 14
Ash % DM 11.2 2.2 8.0 15.3 17
Gross energy MJ/kg DM 18.3 *
 
Minerals Unit Avg SD Min Max Nb
Calcium g/kg DM 9.5 6.6 1.3 19.8 12
Phosphorus g/kg DM 2.9 1.6 0.8 5.7 11
Potassium g/kg DM 24.9 11.8 2.5 41.4 10
Sodium g/kg DM 0.8 0.8 0.9 2
Magnesium g/kg DM 4.0 0.9 3.1 5.7 9
Manganese mg/kg DM 141 1
Zinc mg/kg DM 70 1
Copper mg/kg DM 2 1
Iron mg/kg DM 1690 1
 
Amino acids Unit Avg SD Min Max Nb
Arginine % protein 6.0 0.7 5.2 6.8 5
Glutamic acid % protein 7.9 1.2 6.4 9.6 5
Glycine % protein 5.5 1.0 4.9 7.3 5
Histidine % protein 1.4 0.4 1.1 2.0 5
Isoleucine % protein 5.1 0.4 4.4 5.6 5
Leucine % protein 8.6 0.8 7.5 9.6 5
Lysine % protein 3.6 0.7 2.3 4.0 5
Methionine % protein 1.1 0.6 0.5 2.0 5
Phenylalanine % protein 5.1 0.4 4.5 5.6 5
Threonine % protein 5.0 0.4 4.4 5.4 5
Valine % protein 5.7 0.4 5.2 6.3 5
 
Secondary metabolites Unit Avg SD Min Max Nb
Tannins (eq. tannic acid) g/kg DM 6.2 1

The asterisk * indicates that the average value was obtained by an equation.

References

Bui Phan Thu Hang et al., 2011; CIRAD, 1991; Devendra et al., 1970; Dominguez, 1992; Dongmeza et al., 2009; Hassoun, 2009; Holm, 1971; Le Thi Men, 2006; Luh et al., 1979; Nguyen Nhut Xuan Dung et al., 2002; Pozy et al., 1996; Teguia et al., 1993; Thim Sokha et al., 2008

Last updated on 24/10/2012 00:45:13

Main analysis Unit Avg SD Min Max Nb
Dry matter % as fed 88.5 3.3 84.0 92.6 10
Crude protein % DM 13.2 6.0 7.6 21.7 11
Crude fibre % DM 19.9 4.7 12.2 23.7 7
NDF % DM 40.1 6.3 28.4 50.2 10
ADF % DM 32.2 4.9 25.6 40.1 9
Lignin % DM 11.3 7.3 6.8 29.4 9
Ether extract % DM 2.8 1.3 1.0 5.4 9
Ash % DM 11.8 3.2 5.6 16.6 11
Starch (polarimetry) % DM 1.8 1.2 2.3 2
Total sugars % DM 7.9 6.7 9.0 2
Gross energy MJ/kg DM 17.5 0.9 16.8 18.9 4 *
 
Minerals Unit Avg SD Min Max Nb
Calcium g/kg DM 12.4 2.3 8.0 13.9 6
Phosphorus g/kg DM 3.1 0.8 2.7 4.6 6
Potassium g/kg DM 14.2 12.0 8.2 35.6 5
Sodium g/kg DM 3.7 0.1 3.6 3.7 3
Magnesium g/kg DM 7.0 1.5 4.5 8.3 5
Manganese mg/kg DM 131 29 107 164 3
Zinc mg/kg DM 45 40 21 91 3
Copper mg/kg DM 11 10 5 22 3
 
Amino acids Unit Avg SD Min Max Nb
Alanine % protein 5.6 1
Arginine % protein 6.0 1
Aspartic acid % protein 9.4 1
Glutamic acid % protein 10.0 1
Glycine % protein 4.4 1
Histidine % protein 2.0 1
Isoleucine % protein 4.2 1
Leucine % protein 8.2 1
Lysine % protein 4.8 1
Methionine % protein 1.4 1
Phenylalanine % protein 5.7 1
Proline % protein 4.3 1
Serine % protein 4.1 1
Threonine % protein 4.4 1
Tyrosine % protein 4.1 1
Valine % protein 5.4 1
 
Ruminant nutritive values Unit Avg SD Min Max Nb
OM digestibility, Ruminant % 66.0 1
Energy digestibility, ruminants % 61.8 *
DE ruminants MJ/kg DM 10.8 *
ME ruminants MJ/kg DM 8.8 *
Nitrogen digestibility, ruminants % 33.0 1
 
Pig nutritive values Unit Avg SD Min Max Nb
Energy digestibility, growing pig % 42.5 38.5 46.4 2
DE growing pig MJ/kg DM 7.4 6.6 7.4 2 *
MEn growing pig MJ/kg DM 6.8 6.5 6.9 2 *
NE growing pig MJ/kg DM 4.1 *

The asterisk * indicates that the average value was obtained by an equation.

References

AFZ, 2011; Bui Huy Nhu Phuc et al., 2001; CIRAD, 1991; Dixon, 1986; Du Thanh Hang et al., 2009; Richard et al., 1989; URZ, 2009

Last updated on 24/10/2012 00:45:27

Amino acids Unit Avg SD Min Max Nb
Alanine % protein 6.5 1
Arginine % protein 6.7 1
Aspartic acid % protein 9.1 1
Glutamic acid % protein 11.3 1
Glycine % protein 5.4 1
Histidine % protein 1.6 1
Isoleucine % protein 4.9 1
Leucine % protein 9.8 1
Lysine % protein 6.2 1
Methionine % protein 1.9 1
Phenylalanine % protein 6.2 1
Proline % protein 5.3 1
Serine % protein 4.3 1
Threonine % protein 5.3 1
Tyrosine % protein 4.4 1
Valine % protein 6.2 1

The asterisk * indicates that the average value was obtained by an equation.

References

Walter et al., 1978

Last updated on 24/10/2012 00:45:35

References

References

Antia, B. S. ; Akpan, E. J. ; Okon, P. A. ; Umoren, I. U., 2006. Nutritive and anti-nutritive evaluation of sweet potatoes (Ipomoea batatas) leaves. Pakistan J. Nutr., 5 (2): 166-168 web icon
Aregheore, E. M. ; Tofinga, M., 2004. Influence of type of mulch material on distribution and accumulation of nutrients in sweet potato (Ipomoea batatas) in Samoa. International Journal of Agriculture & Biology web icon
Aregheore, E. M., 2004. Nutritive value of sweet potato (Ipomea batatas (L) Lam) forage as goat feed: voluntary intake, growth and digestibility of mixed rations of sweet potato and batiki grass (Ischaemum aristatum var. indicum). Small Rumin. Res., 51 (3): 235-241 web icon
Ashiono, G. B. ; Ouda, J. O. ; Akuja, T. E. ; Kitilit, J. K. ; Irungu, R. G. ; Gatwiku, S., 2006. Effect of potato vines and sorghum silage on cattle milk productivity. Asian J. Plant Sci., 5 (1): 81-84 web icon
Backer, J. ; Ruiz, M. E. ; Munoz, H. ; Pinchinat, A. M., 1980. The use of sweet potato (Ipomoea batatas, (L) Lam) in animal feeding. II Beef production. Trop. Anim. Prod., 5 (2): 152-160 web icon
Barrios, M. R. ; Rojas, H. V. ; Uzcategui, W., 2002. Determination of the fecal digestibility of diets with different levels of foliage of sweet potatoes (Ipomoea batatas L.) and African palm oil (Elaeis guineensis J.) in pigs. Revista Cientifica, 12 (Suppl. 2): 488-490 web icon
Berhan Tamir; Wude Tsega, 2010. Effects of different levels of dried sweet potato (Ipomoea batatas) leaves inclusion in finisher ration on feed intake, growth, and carcass yield performance of Ross broiler chicks. Trop. Anim. Health Prod., 42 (4): 687-695 web icon
Brown, D. L. ; Chavalimu, E., 1985. Effects of ensiling or drying on five forage species in western Kenya: Zea mays (maize stover), Pennisetum purpureum (Pakistan Napier grass), Pennisetum sp. (bana grass), Ipomoea batatas (sweet potato vines) and Cajanus cajan (pigeon pea leaves). Anim. Feed Sci. Technol., 13 (1-2): 1-6 web icon
Bui Huy Nhu Phuc, 2000. Tropical forages for growing pigs. PhD Thesis, Agraria 247. Swedish University of Agricultural Sciences, Acta Universitatis Agriculturae Sueciae web icon
Bui Huy Nhu Phuc, 2006. Review of the nutritive value and effects of inclusion of forages in diets for pigs. Workshop-seminar Forages for Pigs and Rabbits MEKARN-CelAgrid, Phnom Penh, Cambodia, 22-24 August, 2006 web icon
Canope, J. ; Le Dividich, J. ; Hedreville, F. ; Despois, F., 1977. Influence d'un traitement technologique sur l'efficacité alimentaire des principaux produits amylacés tropicaux: patate douce et banane dans l'alimentation du porc. Nouvelles agronomiques des Antilles et de la Guyane, 3 (3-4): 310
Chedly, K. ; Lee, S, 1999. Silage from by-products for smallholders. FAO Electronic Conference on Tropical Silage web icon
Chhay Ty; Khieu Borin; Chiv Phiny, 2007. A note on the effect of fresh mulberry leaves, fresh sweet potato vine or a mixture of both foliages on intake, digestibility and N retention of growing pigs given a basal diet of broken rice. Livest. Res. Rural Dev., 19 (9) web icon
Chittaranjan, K., 2007. Genome mapping and molecular breeding in plants, Volume 3: Pulses, sugar and tuber crops. Springer-Verlag, Berlin Heidelberg New York web icon
Chiv Phiny; Preston, T. R. ; Khieu Borin, 2010. Effect of fresh mulberry leaves and sweet potato vines on growth performance of pigs fed a basal diet of broken rice. Livest. Res. Rural Dev., 22 (3): 44 web icon
Cornelio, V. M. O. de; Alves, M. I. G. ; Soares, M. C. de, 1988. Raspa de batata-doce para suínos em crescimento e terminação. Pesquisando - EPAMG, Belo Horizonte, MG, no. 185
Devendra, C. ; Göhl, B. I., 1970. The chemical composition of Caribbean feedingstuffs. Trop. Agric. (Trinidad), 47 (4): 335
Dingayan, A. B. ; Fronda, F. M., 1950. A comparative study of the influence of the leaves and young shoots of Centrosema, ipil-ipil, and sweet potato as a green feed on the growth of chicks. The Philippine Agriculturist, 34: 110-115
Doan Thi Gang; Khuc Thi Hue; Dinh Van Binh; Nguyen Thi Mui, 2006. Effect of Guinea grass on feed intake, digestibility and growth performance of rabbits fed a molasses block and either water spinach (Ipomoea aquatica) or sweet potato (Ipomoea batatas L) vines. Workshop on Forages for Pigs and Rabbits, 21-24 August 2006, MEKARN-CelAgrid web icon
Dominguez, P. L., 1992. Feeding of sweet potato to monogastrics. In: Roots, tubers, plantains and bananas in animal feeding. Machin, D.; Nyvold, S. eds. FAO Animal production and health paper 95, FAO, Roma web icon
Dongmeza, E. ; Steinbronn, S. ; Francis, G. ; Focken, U. ; Becker, K., 2009. Investigations on the nutrient and antinutrient content of typical plants used as fish feed in small scale aquaculture in the mountainous regions of Northern Vietnam. Anim. Feed Sci. Technol., 149: 162–178 web icon
Du Thanh Hang ; Nguyen Quang Linh ; Everts, H. ; Beynen, A. C., 2009. Ileal and total tract digestibility in growing pigs fed cassava root meal and rice bran with inclusion of cassava leaves, sweet potato vine, duckweed and stylosanthes foliage. Livest. Res. Rural Dev., 21 (1) web icon
Duke, J. A., 1983. Handbook of Energy Crops. NewCROPS web site, Purdue University web icon
Ecocrop, 2010. Ecocrop database. FAO web icon
Ecoport, 2010. Ecoport database. Ecoport web icon
Etela, I. ; Larbi, A. ; Bamikole, M. A. ; Ikhatua, U. J. ; Oji, U. I., 2008. Rumen degradation characteristics of sweet potato foliage and performance by local and crossbred calves fed milk and foliage from three cultivars. Livest. Sci., 115 (1): 20-27 web icon
Etela, I. ; Oji, U. I. ; Kalio, G. A. ; Tona, G. O., 2008. Studies on sweet potato forage and dried brewers' grains as supplements to green panic for Bunaji cows. Trop. Grassl., 42 (4): 245-251 web icon
Etela, I. ; Larbi, A. ; Ikhatua, U. J. ; Bamikole, M. A., 2009. Supplementing Guinea grass with fresh sweet potato foliage for milk production by Bunaji and N'Dama cows in early lactation. Livest. Sci., 120 (1-2): 87-95 web icon
FAO, 2010. FAOSTAT. Food and Agriculture Organization of the United Nations web icon
Farrell, D. J. ; Jibril, H. ; Perez-Maldonado, R. A. ; Mannion, P. F., 2000. A note on a comparison of the feeding value of sweet potato vines and lucerne meal for broiler chickens. Anim. Feed Sci. Technol., 85 (1-2): 145-150 web icon
Ffoulkes, D. ; Hovell, F. D. DeB. ; Preston, T. R., 1978. Sweet potato forage as cattle feed: voluntary intake and digestibility of mixtures of sweet potato forage and sugar cane. Livest. Res. Rural Dev., 3 (2): 140-144 web icon
Ffoulkes, D. ; Preston, T. R., 1978. Cassava or sweet potato forage as combined sources of protein and roughage in molasses based diets: effect of supplementation with soybean meal. Livest. Res. Rural Dev., 3 (3): 186-192 web icon
French, M. H., 1955. Feeding value of sweet potato tubers. E. Afr. Agric. For. J., 21: 18-19
Göhl, B., 1982. Les aliments du bétail sous les tropiques. FAO, Division de Production et Santé Animale, Roma, Italy web icon
Gonzalez, C. ; Diaz, I. ; Vecchionacce, H. ; Ly, J., 2003. Performance traits of pigs fed sweet potato (Ipomoea batatas L.) foliage ad libitum and graded levels ofprotein. Livest. Res. Rural Dev., 15 (9): 4 web icon
Goyert, J. C. ; Avault, J. W., 1977. Agricultural by-products as supplemental feed for crayfish, Procambarus clarkii. Transactions of the American Fisheries Society, 106: 629-633 web icon
Haryanto, B. ; Johnson, W. L. ; Thomas, N., 1982. Intake preferences for cassava, sweet potato, banana and Napier grass foliages by Indonesian sheep and goats. Proc. 3rd Int. Conf. on Goat Production and Disease, 279 p.
Hoang Huong Giang; Le Viet Ly; Ogle, B., 2004. Evaluation of ensiling methods to preserve sweet potato roots and vines as pig feed. Livest. Res. Rural Dev., 16 (7): 45 web icon
Hoang Nghia Duyet; Truong Thi Thuan; Nguyen Duc Son, 2010. Effects on sow reproduction and piglet performance of replacing soybean meal by a mixture of sweet potato leaves, water spinach and fresh cassava foliage in the diets of Mong Cai and Yorkshire sows. Livest. Res. Rural Dev., 22 (3): 59 web icon
Hoang Nghia Duyet, 2003. The effect of sweet-potato stem levels in the diet on productivity of Mong Cai sows. Science & Technology Journal of Agriculture & Rural Development, 6: 707
Iyeghe-Erakpotobor, G. T., 2007. Effect of concentrate and forage type on performance and digestibility of growing rabbits under sub-humid tropical conditions. Asian J. Anim. Vet. Adv., 2 (3): 125-132 web icon
Kabi, F. ; Bareeba, F. B. ; Havrevoll, Ø. ; Mpofu, I. D. T., 2005. Evaluation of protein degradation characteristics and metabolisable protein of elephant grass (Pennisetum purpureum) and locally available protein supplements. Livest. Prod. Sci., 95 (1-2): 143-153 web icon
Kagya-Agyemang, J. K. ; Hussey, B. ; Amoah, A. B., 2008. Effects of sweet potato leaf meal on the growth performance and carcass characteristics of broiler chickens. Global J. Agric. Sci., 7 (2): 145-147 web icon
Kariuki, J. N. ; Gachuiri, C. K. ; Gitau, G. K. ; Tamminga, S. ; Bruchem, J. van; Muia, J. M. K. ; Irungu, K. R. G., 1998. Effect of feeding napier grass, lucerne and sweet potato vines as sole diets to dairy heifers on nutrient intake, weight gain and rumen degradation. Livest. Prod. Sci., 55 (1): 13-20 web icon
Katongole, C. B. ; Bareeba, F. B. ; Sabiiti, E. N. ; Ledin, I., 2008. Nutritional characterization of some tropical urban market crop wastes. Anim. Feed Sci. Technol., 142 (3-4): 275-291 web icon
Katongole, C. B. ; Sabiiti, E. N. ; Bareeba, F. B. ; Ledin, I., 2009. Performance of growing indigenous goats fed diets based on urban market crop wastes. Trop. Anim. Health Prod., 41 (3): 329-336 web icon
Katongole, C. B. ; Bareeba, F. B. ; Sabiiti, E. N. ; Ledin, I., 2009. Intake, growth and carcass yield of indigenous goats fed market wastes of sweet potato (Ipomoea batatas) vines and scarlet eggplant (Solanum aethiopicum). Trop. Anim. Health Prod., 41 (8): 1623-1631 web icon
Kebede, T. ; Gutu, T. ; Tadesse, E., 2011. Performance and economic efficiency of browsing ArsiBale goats supplemented with sweet potato (Ipomoea batatas L.) vines as replacement for concentrate. Int. J. Livestock Production, 2 (7): 92-99 web icon
Lam My Lan; Duong Nhut Long; Pham Van Manh; Nguyen Van Lanh; Le Thi Ngoc Thanh; Yamada, R. ; Watanabe, T., 2007. Optimal stocking composition in freshwater fish polyculture in Tan Phu Thanh Village, Chau Thanh A District, Hau Giang Province. JIRCAS Working Report, 55: 57-61 web icon
Lanyasunya, T. P. ; Wang, H. R. ; Abdulrazak, S. A. ; Mukisira, E. A., 2006. Effect of supplementation on performance of calves on smallholder dairy farms in Bahati division of Nakuru District, Kenya. Pakistan J. Nutr., 5 (2): 141-146 web icon
Le Thi Men, 2006. Genetic and nutrional diversity of sweet potato (Ipomea batatas), water spinach (Ipomea aquatica) and water hyacinth (Echhornia crassipes) and their potential as pig feed in the Mekong Delta of Vietnam. Proceedings of the Workshop-seminar, 21-24 August 2006, MEKARN-CelAgrid web icon
Le Van An; Tran Thi Thu Hong; Lindberg, J. E., 2004. Ileal and total tract digestibility in growing pigs fed cassava root meal diets with inclusion of fresh, dry and ensiled sweet potato (Ipomoea batatas L. (Lam.)) leaves. Anim. Feed Sci. Technol., 114 (1/4): 127-139 web icon
Le Van An; Tran Thi Thu Hong; Ogle, B. ; Lindberg, J. E., 2005. Utilization of ensiled sweet potato (Ipomoea batatas (L.) Lam.) leaves as a protein supplement in diets forgrowing pigs. Trop. Anim. Health Prod., 37 (1): 77-88 web icon
Le Van An, 2004. Sweet potato leaves for growing pigs: biomass yield, digestion and nutritive value. Doctoral thesis, Swedish University of Agricultural Sciences, Uppsala , Acta Universitatis Agriculturae Sueciae Agraria 470 web icon
Lebot, V., 2009. Tropical root and tuber crops: cassava, sweet potato, yams and aroids. Crop production science in horticulture (17), CAB books, CABI, Wallingford, UK web icon
Lopez, R. G. ; Herrera, J., 1998. Milk production from pastures and cassava (Manihot esculenta) or sweet potato (Ipomoea batatas) integral forage plant supplementation. Cuban J. Agric. Sci., 32 (1): 29-32
Luh, C. L. ; Moomaw, J. C., 1979. Present and future outlook for sweet potato in Asia, research and development needs. In: 5th Symp. Int. Soc. Trop. Root Crops. Manila Philippines, 1-30
Ly Thi Luyen ; Preston, T. R., 2012. Growth performance of New Zealand White rabbits fed sweet potato (Ipomoea batatas) vines supplemented with paddy rice or Guinea grass supplemented with commercial concentrate. Livest. Res. Rural Dev., 24 (7): 127 web icon
Ly, J., 2009. Sweet potato (Ipomoea batatas Lam) for pig feeding. Characteristics of the chemical composition and antinutrional factors. Revista Computadorizada de Producción Porcina, 16 (3):159-171 web icon
Machin, D. ; Nyvold, S., 1992. Roots, tubers, plantains and bananas in animal feeding. Proceedings of the FAO Expert Consultation held in CIAT, Cali, Colombia 21–25 January 1991; FAO Animal Production and Health Paper - 95 web icon
Manfredini, M. ; Badiani, A. ; Chizzolini, R. ; Nanni, N. ; Novelli, E., 1990. Sweet potatoes (Ipomoea batatas) in heavy pig fattening. In: 36th International Congress of Meat Sciences and Technology Havana Cuba, 98-106
Meyreles, L. ; Preston, T. R., 1979. The effect on the performance of fattening bulls of supplementing a basal diet of derinded sugar cane stalk with urea, sweet potato forage and cottonseed meal. Trop. Anim. Prod., 4 (3): 255-262 web icon
Mora, L. ; Dominguez, P. L. ; Calderon, R. ; Quintano, J., 1992. Notes on the use of sweet potato (Ipomoea batatas) foliage in diets for weaned pigs. Zootechnia de Cuba, 2, 85-90
Muir, J. P. ; Massaete, E. S., 1995. Reproductive performance of rabbits fed wheat bran with tropical forages or Leucaena leucocephala. World Rabbit Science, 3 (2): 91-93 web icon
Munguti, J. M. ; Liti, D. M. ; Waidbacher, H. ; Straif, M. ; Zollitsch, W., 2006. Proximate composition of selected potential feedstuffs for Nile tilapia (Oreochromis niloticus Linnaeus) production in Kenya. Die Bodenkultur, 57 (3): 131-141 web icon
Mwanga, R. O. M. ; Wanyera, N. W., 1988. Sweet potato growing and research in Uganda. In: Improvement of sweet potato (Ipomoea batatas) in East Africa, with some references of other tuber and root crops. corps: report of the Workshop on Sweet Potato Improvement in Africa held at ILRAD, Nairobi, Kenya, UNDP Project CIAT-CIP-IITA, September 28-October 2, 1987. International Potato Centre web icon
Nambi, J. ; Mutetikka, D. ; Bareeba, F. B., 2001. Performance of lactating dairy goats fed diets of sweet potato vines, banana peels and maize leaves, supplemented with legume tree foliage. Muarik Bulletin 4: 43-48
Nedunzhiyan, M. ; Reddy, D. S. ; Ravi, A, 2000. Effect of sweet potato vine meal on the digestibility of organic nutrients in pigs. J. Root Crops, 26 (2): 23-25
Ngo Huu Toan; Preston, T. R., 2007. Evaluation of uncultivated vegetables for pigs kept in upland households. Livest. Res. Rural Dev., 19 (10):150 web icon
Nguyen Nhut Xuan Dung; Luu Huu Manh; Udén, P., 2002. Tropical fibre sources for pigs - digestibility, digesta retention and estimation of fibre digestibility in vitro. Anim. Feed Sci. Technol., 102 (1-4): 109–124 web icon
Nguyen Thi Duong Huyen ; Nguyen Xuan Trach ; Preston, T. R., 2013. Effects of supplementation of paddy rice and/or rice grain and/or rice husk to sweet potato (Ipomoea batatas) vines as basal diet on growth performance and diet digestibility in rabbits. Livest. Res. Rural Dev., 25 (1): 19 web icon
Nguyen Thi Duong Huyen ; Nguyen Xuan Trach ; Preston, T. R., 2013. Effects of paddy rice on feed utilization and growth of New Zealand White rabbits fed basal diets of water spinach (Ipomoea aquatica) or sweet potato vines (Ipomoea batatas). Livest. Res. Rural Dev., 25 (6): 100 web icon
Nguyen Thi Hoa Ly; Le Duc Ngoan; Verstegen, M. W. A. ; Hendriks, W. H., 2010. Ensiled and dry cassava leaves, and sweet potato vines as a protein source in diets for growing Vietnamese Large White x Mong Cai pigs. Asian-Aust. J. Anim. Sci., 23 (9): 1205-1212 web icon
Nguyen Thi Tinh; Nguyen The Yen; Mai Thach Hoanh; Pham Ngoc Thach; Peters, D. ; Campilan, D. ; Fuglie, K., 2006. Improving pig feed systems through use of sweetpotato and other local feed resources in Vietnam: A manual for farmers and extensionists to raise pigs more efficiently with locally available feed resources. CIP-UPWARD and CIP-Hanoi web icon
Nguyen Van Thu ; Nguyen Thi Kim Dong, 2008. Effect of water spinach and sweet potato vine associated with 2 other natural plants, on growth performance, carcass values and economic return of growing crossbred rabbits in the Mekong delta of Vietnam. Proc. 9th World Rabbit Congress, Verona, Italy, 10-13 June 2008, 763-768 web icon
Noblet, J. ; Fortune, H. ; Dupire, C. ; Dubois, S., 1990. Valeur nutritionnelle de treize matières premières pour le porc en croissance : 1- Teneurs en énergie digestible, métabolisable et nette. Conséquence du choix du système énergétique. Journées Rech. Porc., 22: 175-184 web icon
Olorunnisomo, O. A., 2007. Yield and quality of sweet potato forage pruned at different intervals for West African dwarf sheep. Livest. Res. Rural Dev., 19 (3): 36 web icon
Olorunnisomo, O. A., 2007. A cost-benefit analysis of sweet potato production for sheep feeding in the southwest of Nigeria. Livest. Res. Rural Dev., 19 (6) web icon
Onwueme, I. C. ; Winston B. C., 1994. Tropical root and tuber crops: production, perspectives and future prospects. FAO Plant production and protection paper, 126. FAO, Rome web icon
Orodho, A. B. ; Alela, B. O. ; Wanambacha, J. W. ; , 1996. Use of sweet potato [Ipomoea batatas (L.) Lam] vines as starter feed and partial milk replacer for calves. In: Sustainable feed production and utilization for smallholder livestock enterprises in Sub-Saharan Africa (J. Ndikumana and P.N. de Leeuw, Eds), Proc. 2nd African Feed Resources Network (AFRNET), Harare, Zimbabwe, 6–10 December, 1993, AFRNET (African Feed Resources Network), Nairobi, Kenya (1996) 201 pp web icon
Ørskov, E. R. ; Nakashima, Y. ; Abreu, J. M. F. ; Kibon, A. ; Tuah, A. K., 1992. Data on DM degradability of feedstuffs. Studies at and in association with the Rowett Research Organization, Bucksburn, Aberdeen, UK. Personal Communication
Oyenuga, V. A., 1968. Nigeria's foods and foodstuffs. Ibadan, University Press
Padmaja, G., 2009. Uses and nutritional data of sweet potato. In: Loebenstein, G.; Thottapilly, G. The sweetpotato. Springer web icon
Paneque Ramirez, 1992. Cultivation harvesting and storage of sweet potato products. In: Roots, tubers, plantains and bananas in animal feeding. (Eds Machin, D.; Nyvold, S.), Proceedings of the FAO Expert Consultation held in CIAT, Cali, Colombia 21–25 January 1991; FAO Animal Production and Health Paper - 95 web icon
Peñaflorida, V., 1995. Growth and survival of juvenile tiger shrimp fed diet where fish meal is partially replaced with papaya (Carica papaya L.) or camote (Ipomea batatas Lam.) leaf meal. Israeli J. Aquacult. Bamidgeh, 47 (1): 25–33 web icon
Preston, T. R., 2006. Forages as protein sources for pigs in the tropics. Workshop-seminar, 21-24 August 2006, MEKARN-CelAgrid web icon
Raharjo, Y. C. ; Cheeke, P. R., 1985. Palatability of tropical tree legume forage to rabbits. Nitrogen Fixing Tree Research Reports, 3: 31-32
Rodriguez, A. ; Gonzalez, C. ; Diaz, V. ; Vecchionacce, H. ; Hurtado, E., 2003. Effect of lipids and zeolite incorporation on total apparent digestibility of diets with sweet potato (Ipomoea batatas l.) foliage in pigs. Cuban J. Agric. Sci. 37: 421-424 web icon
Rondon, Z. ; Combellas, J. de; Arvelo, C., 1989. Growth of lambs grazing on sweet potato leaves (Ipomoea batatas). Informe anual, Universidad Central de Venezuela, Facultad de Agronomia, Instituto de Produccion Animal, 1987.: 100-101
Scott, G. J. ; Wiersema, S. G., 1993. Product Development for Root and Tuber Crops: Africa (vol.3). International Potato Center, Princess I. Ferguson, Centro Internacional de Agricultura Tropical, International Institute of Tropical Agriculture web icon
Scott, G. J., 1992. Sweet potato as animal feed in developing countries: present patterns and future prospects. In: Roots, tubers, plantains and bananas in animal feeding. Machin, D. and Nyvold, S. eds, Proc. FAO Expert Consultation held in CIAT, Cali, Colombia 21–25 January 1991; FAO Animal Production and Health Paper - 95 web icon
Teguia, A. ; Tchoumboue, J. ; Mayaka, B. T. ; Tankou, C. M., 1993. The growth of broiler chickens as affected by the replacement of graded levels of maize by sweet potato leaves (Ipomea batatas) or Ndole (Vernonia spp.) in the finisher diet. Anim. Feed Sci. Technol., 40 (2-3): 233-237 web icon
Tomita, Y. ; Hayashi, K. ; Hashizume, T., 1985. Palatability of pigs to sweet potato-silage and digestion trial by them. Bulletin of the Faculty of Agriculture, Kagoshima University No. 35:75–80
Vo Lam; Ledin, I., 2004. Effect of feeding different proportions of sweet potato vines (Ipomoea batatas L. (Lam.)) and Sesbania grandiflora foliage in the diet on feed intake and growth of goats. Livest. Res. Rural Dev., 16 (10) web icon
Walter, W. M. ; Purcell, A. E. ; Mc Collum, G. K. J., 1978. Laboratory preparation of a protein-xanthophyll concentrate from sweet potato leaves. Agric. Food Chem., 26 (5): 1222 web icon
Woolfe, J. A., 1992. Sweet potato: an untapped food resource. Cambridge University Press, 643 p. web icon
Wude Tsega; Berhan Tamir, 2009. The effect of increasing levels of dried leaves of sweet potato (Ipomoea batatas) on dry matter intake and body weight gain performance of broiler finisher chicke. Livest. Res. Rural Dev., 21 (12) web icon

Image credits

Image credits

Picture title Credits License
Sweet potato leaves, North Vietnam Gilles Tran, AFZ CC BY 3.0