Pasture and green forage
Guar was found to be not very suitable for grazing due to its hairy leaves and unpalatability (Göhl, 1982). Guar is sometimes grazed to reduce the risk of bloat in ruminants (Wong et al., 1997). Palatability improves after cutting and wilting (Göhl, 1982). The best time for cutting guar for fodder is during flowering and early pod formation (Wong et al., 1997).
In sheep, guar forage from two successive cuts was found to be palatable and digestible, with a DMI of 2.42% LW (Abd El-Baki et al., 1997). When offered ad libitum, it was more palatable than Cenchrus ciliaris straw and Vigna aconitifolia forage and resulted in higher dry matter intake and live-weight gain (Mathur et al., 2005).
Guar hay cut at flowering was able to maintain the body weight of rams for 45 days with a DMI of 2.44% LW (Patnayak et al., 1979). In goats, guar hay cut at pod formation gave identical nutrient and energy intakes and digestibility to the mixture of guar hay and crushed oats (Pachauri et al., 1986).
In lactating cows, guar crop residues containing the stems, leaves and immature pods left after threshing, compared favourably to cajan pea (Patel et al., 1972). Guar straw can be incorporated up to 70% in the diet of adult sheep to provide maintenance without any adverse effects (Singh et al., 2008). Crop residues are also used for feeding camels in the arid regions of India (Bhakat et al., 2009; Saini et al., 2006).
Raw guar meal can constitute up to 25% of cattle rations. Processed meal can be used as the sole protein component of cattle diets (Göhl, 1982).
Few nutritive values have been determined: total N degradability for expanded guar meal was in the 65-75% range and was influenced by the amount of heat treatment applied during processing. Total N degradability for unprocessed meal was 85% (Lund et al., 2008). The only reported OM digestibilities are 76% and 71% for the processed and unprocessed meal respectively (Islam Shah et al., 1964).
In dairy cows, palatability problems have been reported when more than 5% guar meal was included in the diet. However, dairy cows and heifers fed rations containing 10-15% guar meal became acquainted to its odor and taste after a few days. Intake remained lower than with the control diet (cottonseed meal) but milk yield was not affected. In growing dairy calves, flavoured guar meal and toasted guar meal gave slightly better rates of intake and gain than raw guar meal during the first month of feeding (Rahman et al., 1968).
In beef cattle, steers fed raw and toasted guar meal (2.8 kg/head/day with ad libitum sorghum silage) exhibited mild scouring and showed signs of reluctance to eat for a few days, but final average daily gain was comparable to that obtained with a cottonseed meal-based control diet (Conrad et al., 1967).
In growing male buffalo calves, guar meal fed at 50% of ME intake was found to be a better energy and protein supplement than groundnut meal, being more digestible, and giving a better growth rate and feed conversion efficiency (Mandal et al., 1989a; Mandal et al., 1989b). The animals also showed a positive response in sperm motility, plasma LH and testosterone compared to those fed groundnut meal (Lohan et al., 1989).
In lambs, guar meal diets initially resulted in disappointing growth rates, but after acclimatization to the diet growth rates improved and the animals showed signs of compensation (Huston et al., 1971). Sheep fed diets containing 50:50 guar meal and maize (ad libitum diets alone or ad libitum diets combined with grazing) had better meat yields than sheep grazing without a supplement (Rohilla et al., 2007). Rumen-protected (formaldehyde) guar meal supplemented with urea resulted in higher growth than raw or unsupplemented guar meal (Mathur et al., 1989).
In a comparison of several legume seeds in the Southern Great Plains of the USA, the protein and in vitro digestible DM of guar seeds indicated that they could be efficient replacements for maize or cottonseed meal in livestock diets, assuming that guar could generate enough grain biomass to be cost-effective. Though not as effective as soybean, guar seeds were capable of accumulating useful levels of protein and digestible dry matter under the variable growing conditions of the study (Rao et al., 2009).
Boiled (slow heat) guar seeds fed with wheat straw (40% of ME) to male buffalo calves resulted in adequate nutrients utilization and availability of undegraded dietary protein (Tiwari et al., 1990).
Crushed guar seeds increased dry matter intake and digestibility when included at 150 g/head in Marwari ewes grazing sewan grass (Lasiurus scindicus) (Thakur et al., 1985).