« back    next »

Horse, sheep and other specialty diets

Since canola meal is so widely available, feed manufacturers have used it in many specialty feeds. Given that research in some of these specialty areas is very limited, the commercial application of canola meal has sometimes been demonstrated and accepted without the benefit of formal research. There are very few, if any, specialty feed areas where canola meal has not found acceptance. Canola meal is increasingly used in aquaculture feeds for salmon, trout, catfish, carp, tilapia, shrimp and minor species. It is routinely used in diets for horses, sheep, rabbits and other specialty animals.

Aquaculture Diets

Canola meal is well established as a feed ingredient in salmon and trout diets where it has been routinely fed for over 20 years (Higgs et al., 1996). Canola meal is used at up to 20% inclusion levels in salmonid diets, above which the negative effects of glucosinolates on the thyroid gland and fish growth rate manifest themselves. High fibre and/or phytate concentrations in canola meal are also an issue with respect to decreased nutrient digestibility and are also partly responsible for the 20% maximum recommended inclusion level. There is work (Mwachireya et al., 1999) to develop high protein concentrates from canola meal whereby the glucosinolates, fibre and phytate are reduced and the protein level increased in order to produce an ingredient that is substitutable for fishmeal. As well, salmon and trout are very sensitive to nutrient digestibility differences between different batches of canola meal (Burel et al., 2000). These authors also noted that there was no effect on feed intake over canola meal inclusion levels ranging from 0 to 50%.

Canola meal is also used in diets for other aquacultural species such as catfish, carp, tilapia and shrimp. Lim et al., (1997) found that canola meal can be included in channel catfish diets at up to 31% inclusion levels with no negative effects on performance. Canola meal and rapeseed meal are also commonly included in carp diets, which are normally vegetable protein based. Higgs et al. (1989) determined that canola meal could be effectively used at a 10% inclusion level in juvenile tilapia diets without significantly depressing growth rate or feed conversion efficiency. Abdul-Aziz et al., (1999), on the other hand, fed up to 25% canola meal in tilapia diets with no effects on performance. In the case of shrimp, Lim et al., (1998) found that 15% canola meal in shrimp diets resulted in no significant performance differences but that 30% and 45% inclusion levels resulted in growth rate and feed intake depression. A non-nutritional concern about using canola meal in shrimp feeds is the negative effects that the fibre in canola meal has on feed pellet water stability.

In addition to the above, canola meal has also been fed to bass, perch, seabream and turbot, indicating a general acceptance of canola meal in aquaculture diets.

Horse Diets

Even though there are only a handful of research studies (Cymbaluk, 1990; Sutton, 1988) using canola meal in horse feeds, it is commonly used at relatively high inclusion levels. Sutton (1988) investigated potential concerns about canola meal palatability by horses. He determined that up to 15% canola meal, the highest level tested, in recreational horse diets had no effects on feed intake.

Sheep Diets

Canola meal is widely fed to all types of sheep and there are no effects on feed intake or other performance parameters (Hill, 1991). In fact, sheep can apparently tolerate high glucosinolate rapeseed meal quite well. Vincent et al., (1990) fed diets containing 21% rapeseed meal (18 ?moles/g of glucosinolates in the concentrate) to lambs with no negative effects on feed consumption or growth rate. Vincent et al., (1988) fed ewes a diet containing 20% high glucosinolate rapeseed meal (17 ?moles/g of glucosinolates in the concentrate) with no negative effects on feed intake, milk production, number of lambs per ewe or lamb birth weight. In fact milk production was numerically higher on the rapeseed meal diet (3.25 kg/day) compared to the soybean meal control diet (3.14 kg/day). Recently, Mandiki et al., (1999) fed lambs diets containing up to 30% canola quality rapeseed meal (6.3 ?moles/g of glucosinolates in the concentrate). There were no effects on weight gain or feed intake, despite the fact that thyroid weight was marginally higher and thyroid hormone production was marginally lower at the high dietary inclusion levels of rapeseed meal.

The processing temperature of canola meal may be important in feeding sheep.? Konishi et al., (1999) recently demonstrated that excessive heat processing of canola meal suppressed phytate degradation in the rumen and led to lower availability of dietary phosphorus. The extent that phytate degradation decreased was greater in canola meal than in soybean meal. Petit et al., (1997) observed a somewhat different effect of heat treatment. They compared dietary nutrient degradability in the rumen of raw and extruded whole soybeans and canola seed in growing lambs. They found that extrusion of canola seed increased dry matter and nitrogen degradability but extrusion decreased soybean nitrogen degradability.

Miscellaneous Diets

For other ?iscellaneous· animals there is very little published research on feeding canola meal. Commercially, it is quite common to feed canola meal to rabbits as the main dietary protein supplement. This is supported by the early research of Lebas and Colin, (1977) and Throckmorton et al., (1980). Likewise, in early work with mink, Belzile et al., (1974) showed that rapeseed meal is a suitable dietary protein source. In the case of ratites, Brand et al., (2000) have shown that canola meal has a high metabolizable energy value for ostriches.

Canola meal maximum inclusion levels

The recommended maximum inclusion levels, together with the reasons why, for canola meal usage in aquaculture and specialty diets is given in Table 1.

Table 1 Recommended maximum inclusion levels (%) of canola meal in aquaculture and specialty diets

Animal diet type	Maximum inclusion level	Reasons for maximum inclusion level
Salmon, Trout	20	Glucosinolates, fibre, phytate
Catfish	30
Tilapia	25
Prawns	15	Fibre
Horses	15
Sheep	30

References

Abdul-Aziz, G.M., M.A. El-Nady, A.S. Shalaby and S.H. Mahmoud. 1999.
Partial substitution of soybean meal protein by different plant protein sources in diets for Nile tilapia fingerlings. Bulletin of Faculty of Agriculture, U. of Cairo. 50:189-202.

Belzile, R.J., L.S. Poliquin and J.D. Jones. 1974.
Nutritive value of rapeseed flour for mink: effects on live performance, nutrient utilization, thyroid function and pelt quality. Can. J. Anim. Sci. 54:639-644.

Brand, T.S., L. De Brabander, S.J. Van Schalkwyk, B. Pfister and J.P. Hays. 2000.
The true metabolisable energy content of canola oilcake meal and full-fat canola seed for ostriches (Struthio camelus). Brit. Poult. Sci. 41:201-203.

Burel, C., T. Boujard, A.M. Escaffre, S.J. Kaushik, G. Boeuf, K.A. Mol, S. Van der Geyten and E.R. Kuhn. 2000.
Dietary low-glucosinolate rapeseed meal affects thyroid status and nutrient utilization in rainbow trout (Oncorhynchus mykiss). Brit. J. Nutr. 83:653-664.

Cymbaluk, N.F. 1990.
Using canola meal in growing draft horse diets. Equine Practice 12:13-19.

Higgs, D.A., B.S. Dosanjh, M. Little, R.J.J. Roy and J.R. McBride. 1989.
Potential for including canola products (meal and oil) in diets for Oreochromis mossambicus x O. aureus hybrids. Proc. Third. Int. Symp. on Feeding and Nutr. in Fish. Toba, Japan. Aug. 28 ·Sep. 1, 1989. Pp. 301-314.

Higgs, D.A., B.S. Dosanjh, R.M. Beames, A.F. Prendergast, S.A. Mwachireya and G. Deacon. 1996.
Nutritive value of rapeseed/canola protein products for salmonids. In Eastern Nutrition Conference, pp. 187-196. Halifax, Canada, May 15-17.

Hill, R. 1991.
Rapeseed meal in the diets of ruminants. Nutrition Abstracts and Reviews (Series B) 61(3).

Konishi, C., T. Matsui, W. Park, H. Yano and F. Yano. 1999.
Heat treatment of soybean meal and rapeseed meal suppresses rumen degradation of phytate phosphorus in sheep. Anim. Feed Sci. Technol. 80:115-122.

Lebas, F. and M. Colin. 1977.
Utilization of rapeseed oil meal in growing rabbit feeding. Effect of dehulling. Ann. Zootech. 26:93-97.

Lim, C., R.M. Beames, J.G. Eales, A.F. Prendergast, J.M. McLeese, K.D. Shearer and D.A. Higgs. 1997.
Nutritive values of low and high fibre canola meals for shrimp. Aquaculture Nutrition. 3:269-279.

Lim, C., P.H. Klesius and D.A. Higgs. 1998.
Substitution of canola meal for soybean meal in diets for channel catfish. Ictalurus punctatus. J. World Aquaculture Soc. 29:161-168.

Mandiki, S.N.M., J.L. Bister, G. Derycke, J.P. Wathelet, N. Mabon, N. Marlier and R. Paquay. 1999.
Optimal level of rapeseed meal in diets of lambs. Proceedings 10th International Rapeseed Congress, Canberra, Australia, 1999.

Mwachireya, S.A., R.M. Beames, D.A. Higgs and B.S. Dosanjh. 1999.
Digestibility of canola protein products derived from the physical, enzymatic and chemical processing of commercial canola meal in rainbow trout Oncorhynchus mykiss (Walbaum) held in fresh water. Aquaculture Nutrition. 5:73-82.

Sutton, E.I. 1988.
Canola meal for other species. Horses. Feed intake and performance. Canola Nutritionist Manual. Canola Council of Canada. Winnipeg, Manitoba.

Throckmorton, J.C., P.R. Cheeke and N.M. Patton. 1980.
Tower rapeseed meal as a protein source for weanling rabbits. Can. J. Anim. Sci. 60:1027-1028.

Vincent, I.C., H.L. Williams and R. Hill. 1988.
Feeding British rapeseed meals to pregnant and lactating ewes. Anim. Prod. 47:283-289.

Vincent, I.C., J. Thompson and R. Hill. 1990.
The voluntary feed intake and weight gain of lambs given concentrate feeds containing rapeseed meal with a range of glucosinolate contents. Anim. Prod. 50:587.

« back next »