Cotton seeds are high in energy (due to their fat content), crude protein and fibre, and are consequently a good supplement for dairy and fattening ruminants. Whole cottonseed may be used as a feed for mature cattle, as it’s often done where adequate milling equipment is not available. The seedes are usually soaked in water and fed in small quantities as a supplement to green feed (Göhl, 1982). Due to the presence of gossypol (See Potential constraints), cotton seeds must not be given to young ruminants before they have a mature functional rumen. However, 2 experiments with calves fed on 15% or 25% cottonseeds reported no detrimental effect on calves performance or health due to gossypol (Bernardes et al., 2007; Anderson et al., 1982). Given the detrimental effects of gossypol on reproduction, cotton seeds must be limited or avoided in diets for reproductive males and females.
Energy source
Because the energy of cotton seeds is mainly provided by their fat content, methane production in the rumen is lower than that obtained with fermentable carbohydrates (Arieli, 1998). Cotton seeds provide by-pass energy in the form of long chain fatty acids that are released in the rumen after oil hydrolysis. The addition of cotton seeds was found to greatly reduce the numbers of protozoa, because excessive fat in the rumen may have a detrimental effect on cellulolytic bacteria (Bird et al., 1987). Because of its high fat content it may be recommended to limit cotton seeds in order not to exceed about 6% of the total fat content in the diet. It can be an interesting source of energy when incorporated at up to 15% of the diet for steers in a hot and humid climate. Those animals show less thermal stress (lower respiration and sweating rates), maintain their body temperature with a lower water consumption and have a better overall performance (Umpapol et al., 2011).
Protein source
Cotton seeds are a protein source. Delinting tends to decrease the fibre content and increase the protein and oil concentrations (Göhl, 1982). Cottonseed protein is highly degradable: soluble proteins (albumin and globulin) make up 75% of total proteins and rumen protein degradability values are usually over 70% (Arieli, 1998).
In vivo digestibility of diets including cotton seeds
When cotton seeds are introduced into a diet, the crude fat digestibility generally increases (Karalazos et al., 1992; Polviset et al., 2010; Silva et al., 2010); and fibre (ADF) digestibility may decrease (Hill et al., 2008; Polviset et al., 2010) or increase (Karalazos et al., 1992). Apparent DM or OM digestibility of the whole diet does not change.
Animal |
Experiment |
Inclusion rate |
Effect on DMD |
Effect on OMD |
Effect on DMI |
Reference |
Sheep |
Substitute for maize grain in concentrate + hay |
175, 355, 530 g/d |
Decreases from 74 to 63% |
|
No effect |
Karalazos et al., 1992 |
Dairy goat |
Substitute for soybean meal |
13% (320 g/d) |
Tends to decrease (58 vs. 60%) |
Decreases (59 vs 62%) |
No effect |
Silva et al., 2010 |
Steers |
Increasing levels + hay |
1.2 kg/d, 2.3 kg/d or ad lib. |
- |
Decreases from 75 to 63% at ad libitum (3.7 kg/d) |
Hay DMI decreases |
Hill et al., 2008 |
Steers |
Increasing levels in TMR |
10, 20 or 30% |
- |
Decreases from 82% (10% inclusion rate) to 75% (20 or 30% inclusion rates |
|
Neill et al., 1989 |
Steers |
Increasing levels in concentrate + straw |
15 or 30% |
No effect (80%) |
No effect (82%) |
No effect |
Polviset et al., 2010 |
TMR= total mixed ration; DMD= in vivo apparent dry matter digestibility; OMD= in vivo apparent organic matter digestibility; DMI= dry matter intake
Dairy cows
The response of dairy cows in terms of DM intake when cotton seeds are used as a supplement depends on climatic conditions, on dietary factors such as fat, fibre and energy content, and possibly on diet protein degradability (Arieli, 1998). Whole cotton seeds included into dairy cows diets up to 25% did not affect DM intake but had a positive effect on milk fat content and a negative effect on milk protein content. Milk fat composition changed, resulting in a decrease in C6-C12 fatty acids and in an increase in stearic and total oleic acids (Coppock et al., 1987). High levels of cotton seeds (3.5 kg/d) offered for a long period (5 months) to supplement the diets of dairy cows (548-557 kg, 25 kg milk) significantly impaired fat and carbohydrate metabolism, measured by liver function. However, this effect was reversible when cotton seed supplementation was stopped for 2 months (Girginov et al., 2008). The following table presents dairy cow trials with cotton seeds included in the diet.
Country |
Breed |
Experiment |
Inclusion rate on DM basis, except where stated |
Results |
Reference |
USA |
Holstein |
Comparison of cotton seeds or cracked cotton seeds in TMR |
3 or 10% |
No effect on DMI (24 kg/d), milk yield (34.6 kg/d for primipares, 45 kg/d for multipares) and milk fat (3.5 %) |
Santos et al., 2002 |
USA |
|
Dose comparison in TMR |
0 or 15% |
DMI increased by 0.7 kg/d, milk yield by 0.9-1.4 kg/d and milk fat by 0.3% |
Risco et al., 1998 |
Greece |
Friesian (600kg) |
Comparison cotton seeds vs. cottonseed meal in concentrate plus maize silage and straw diet |
20% on fresh basis |
Milk yield increased by 2 kg/d and milk fat by 0.42% |
Belibasakis et al., 1995 |
USA |
Holstein |
Comparison of cotton seeds or crushed cotton seeds in TMR |
12.8% |
No effect on DMI (25-28 kg/d), milk yield (38.5-40 kg) and milk fat (3.9-4%) for primipares and multipares respectively. Slight differences in milk fatty acids composition |
Prieto et al., 2003 |
Argentina |
Holstein |
Comparison of GM cotton seeds and non GM cotton seeds in TMR |
10% |
No effect on DMI (22-23 kg/d), body weight (540-567 kg), milk yield (27 kg/d) and milk composition |
Castillo et al., 2004 |
USA |
Holstein |
Comparison of cotton seeds to cottonseed meal or SBM in TMR |
13.50% |
No effect on DMI (20.7-22.7 kg/d), milk yield (28.6-30.8 kg/d) and milk composition |
Mena et al., 2004 |
China |
Holstein |
Comparison TMR with or without cotton seeds |
10% |
No effect on DMI (18–21 kg/d) and milk yield (23-30 kg/d); milk protein increased (3.2 vs. 3.4%). Milk fat tended to increase |
Chen et al., 2008 |
Turkey |
Holstein (500 kg) |
Increasing cotton seeds levels in a diet based on maize silage and concentrate |
0, 12.5, 25, or 37.5% |
No effect on milk yield (18.3-20.5 kg/d) and milk fat (4-4.1%) |
Oguz et al., 2006 |
Thailand |
Holstein Friesian (450 kg) |
Comparison of cracked or not cotton seeds in TMR |
10% |
No effect on DMI (15.2-15.9 kg/d), milk yield (16.2-16.6 kg/d) and milk composition |
Wongnen et al., 2009 |
India |
Lactating Murrah buffaloes |
Comparison between transgenic (Bt) and non-transgenic cotton seeds in a concentrate (4.5 kg/d) with forage |
Up to 40% |
No effect on forage DM intake (11.8-12 kg/d) and body weight gain (426-494 g/d) |
Singh et al., 2003 |
Beef cows
In dry pregnant cows (520-580 kg BW) fed tropical hay and cotton seeds offered ad libitum (average intake 4 kg cotton seed DM), or relative to body weight (0.25% or 0.5%), hay DMI was higher at ad libitum and 0.5% BW level than at 0.25% BW level (11.5 vs. 9.5 kg). No diarrhea or other adverse effects were observed even when the cotton seeds were offered ad libitum. The average daily weight gain increased from 360 g/d to 590 g/d with increasing cotton seeds intake. Beef cows offered hay supplemented with cotton seeds at 0.5% BW from the end of gestation to 90 days after calving had higher BW gains than when not supplemented and calves were not affected (birth weight and weight gain) by their mother's diet (Hill et al., 2008).
Growing cattle
The following table presents growing cattle trials with cotton seeds included in the diet.
Country |
Animal |
Experiment |
Inclusion rate on DM basis |
Main results |
Reference |
Brazil |
Calves |
From birth to 3 months |
15% |
No clinical evidence of gossypol intoxication. Same daily weight gain and DMI than for diets without cotton seeds |
Bernardes et al., 2007 |
USA |
Calves |
From birth to 3 months |
25% |
No health problems. Higher daily weight gain and DMI than for diets without cotton seeds |
Anderson et al., 1982 |
USA |
Holstein steers (379-394 kg) |
Comparison of cotton seeds and various cotton seeds processed (cracked, roasted, cracked + roasted, extruded) in TMR |
15% |
No difference in DMI (9.6-10.3 kg/d) or ADG (1410-1890 g/d) excepted with roasted and cracked cotton seeds resulting in lower rate of gain (1290 g/d) |
Santos et al., 2005 |
USA |
Holstein steers (423-432 kg) |
Comparison of various cotton seeds and cottonseed meal levels in TMR |
7 or 14% |
No difference in DMI (9.2-10.3 kg/d) or ADG (1040-1400 g/d) |
Santos et al., 2005 |
USA |
Holstein steers (473-497 kg) |
Comparison of two genus of cotton seeds cracked or not |
15% |
No difference in DMI (9.1-10.1 kg/d) or ADG (1000-1500 g/d) |
Santos et al., 2005 |
Australia |
Brahman-cross steers (350 kg) |
Comparison of various levels of cotton seeds in finishing diet |
10, 20 or 30% |
No difference in OMI (5,3-6,5 kg/d) and ADG (810-860 g/d) |
Neill et al., 1989 |
USA |
Crossbred (340 kg) |
Comparison of cotton seeds to cottonseed meal and husk in TMR |
30% |
DMI tended to decrease with cotton seeds (5.0 vs 6.3 kg/d) |
Moore et al., 1986 |
USA |
Angus x Polled Hereford (457 kg) |
Hay based diet supplemented at various cotton seeds levels |
0.25, 0.30 % BW or ad libitum |
Increasing levels of cotton seeds intake decreased hay DMI from 5.9 kg/d (0 cotton seeds) to 4.5 kg/d (ad libitum cotton seeds). Maximum cotton seeds DMI was 3.7 kg/d |
Hill et al., 2008 |
Thailand |
Crossed Charolais (425 kg) |
Comparison of various levels of cotton seeds in concentrate offered at fixed amount with rice straw |
0, 5, 10, 15% |
No effect on straw DMI (6.58 kg/d). ADG and carcass dressing % increase from 621 g/d (0%) up to 700-720 g/d (10 and 15%) and from 56.5% to 64% respectively |
Umpapol et al., 2011 |
TMR= total mixed ration; DMI= dry matter intake; OMI= organic matter intake; ADG= average daily weight gain; BW= body weight
Sheep
The following table presents sheep trials with cotton seeds included in the diet.
Country |
Animal |
Experiment |
Inclusion rate on DM basis |
Results |
Reference |
Iran |
Lambs, 30 kg |
In a complete TMR containing cotton seeds |
8% and 18% |
At 8%: increased diet DMI, daily weight gain and slaughter results (hot carcass, dressing percentage) with no adverse effect on internal organs. At 18% all results decreased () |
Absalan et al., 2011 |
Brazil |
Santa Ines lambs |
In a complete diet containing cotton seeds |
Up to 40% |
No effect on daily weight gain, slight change of meat fatty acid profile |
Madruga et al., 2008 |
Brazil |
Santa Ines lambs |
In a complete diet containing cotton seeds |
Up to 40% |
Better meat quality (physical and sensory parameters) with no adverse effect |
Vieira et al., 2010 |
Goats
The following table presents goats trials with cotton seeds included in the diet.
Country |
Animal |
Experiment |
Inclusion rate on DM basis |
Results |
Reference |
Australia |
Dairy goats |
Protected cotton seeds replacing up to 80% of a mixture of rapeseed meal and soybean meal |
Up to 80% |
Changes in milk fatty acid: increase in linoleic (C18:2) and stearic (C18:0) acids, and decrease in oleic (C18:1) acid |
Gulati et al., 1997 |
Niger |
Dairy goats, local breed, 32.7 kg |
During the first 8 weeks of lactation |
400 g/d |
Average milk yield of 447 g/d, milk fat 5.2%, milk protein 3.9% |
Djibrillou et al., 1998 |
Burkina Faso |
Dairy goats |
8 weeks after the 1st week of lactation |
0 to 33% |
No effect on DM (1-1.1 kg/d) and milk yield (0.7-0.8 kg/d), but an increase in milk fat (4.6% without cotton seeds to 6.1% with 33% cotton seeds) and a decrease in milk protein (3.8 to 3.2%) |
Ouedraogo et al., 2000 |
Brazil |
Dairy goats, Saanen |
Partial replacement for soybean meal |
13% |
No effect on milk yield (1.1 kg/d) but increase in milk fat (3 to 3.4%) |
Silva et al., 2010 |
Effect of gossypol
Ruminants with a well developed microbial rumen population are able to detoxify gossypol by binding it to amino acids in the rumen (Santos et al., 2002). However, the detoxifying mechanism can be overwhelmed when excessive gossypol content is combined to a low protein concentration in the rumen (Risco et al., 1998). As a result, gossypol may have detrimental effects on health and reproduction (see below). Free gossypol content can be significantly reduced (from 63 to 85%) by various processes such as roasting, cracking and roasting or extrusion. Iron also has a detoxifying effect and adding Fe as iron sulphate (up to 500 mg/g DM of the diet) to steer diets decreased gossypol in plasma (Santos et al., 2005).
Because the rumen becomes functional between 6 and 8 weeks, young ruminants with undeveloped rumen such as lambs and calves should not be fed with cotton seeds (Martin, 1990). Ruminants from 8 to 24 weeks old can tolerate up to 200 mg/kg of dietary free gossypol and older animals can tolerate up to 600 mg/kg without adverse effects (Risco et al., 1998).
Gossypol has no marked effect on production (milk, growth) in adult animals except when very high levels of cotton seeds are used. However, gossypol has a negative effect on gonads and reproduction, primarily in male ruminants but females can also be affected (Randel et al., 1992).
Females
Most of the studies conducted on dairy cows at various lactation stages showed no effect of gossypol on DMI or on milk production and composition, though plasma gossypol increased with increasing levels of gossypol in the diet (Mena et al., 2004). Gossypol was found to decrease hemoglobin content in adult dairy cows (Risco et al., 1998). It increased erythrocyte fragility in young heifers given 30% whole cotton seeds for a long period (over 200 days) (Colin-Negrete et al., 1996) and in adult dairy cows fed 13.5% cotton seeds (corresponding to 20.1 g/d of total gossypol intake) for a shorter duration (84 days) (Mena et al., 2004).
Ruminant females seem to be relatively insensitive to the negative effects of gossypol on fertility (Randel et al., 1992). In growing dairy heifers fed 15% or 30% cotton seeds for a long period (over 400 days), there was no effect of the cotton diet on body weight at onset of puberty and on pregnancy rates (Colin-Negrete et al., 1996). Dairy cows receiving a diet with 15% cotton seeds (20 g/d total gossypol) did not show reproduction problems after 120 days (Risco et al., 1998). However, dairy cows fed for more than 170 days after calving with a diet containing 10% of cotton seeds or a mixture of cotton seeds and cracked cotton seeds (22.8 and 17.5 g/d of free gossypol respectively) showed lower fertility, conception rate and higher abortions when plasmatic gossypol was high (Santos et al., 2003b). Dairy heifers fed 33% to 67% cotton seeds (14.7 g/d of free gossypol) showed a lower quality and viability of embryo and reduced embryo development (Villaseñor et al., 2008). Globally, gossypol has a negative effect on early embryo development and survival (Zirkle et al., 1988; Galvao et al., 2006).
Males
Gossypol may have detrimental effects on male reproduction with marked testicular and spermatogenic epithelium damage (Randel et al., 1992; Chase et al., 1994; Arshami et al., 1988; Risco et al., 1998). When cotton seeds are removed from the diet, animals partly recovered their testicular normality after 2 months damage (Arshami et al., 1988). Young Brahman bulls fed with 41% cotton seeds reach puberty later than those fed with soybean meal (613 vs. 550 days) but with no difference in quality and quantity of semen (Chase et al., 1994). However, adult Holstein bulls fed a diet containing 25 or 35% cotton seeds for 120 days showed abnormalities in terms of semen volume, concentration and other criteria (Smith et al., 1991). In growing male lambs, cotton seeds fed for about 8 months at 20, 30 or 40% did not affect daily weight gain, testis formation and weight, and semen volume and concentration. However, sperm motility and vigour decreased when the diet contained 20% or more cotton seeds, and total sperm defects also increased with increasing cotton seeds levels (Cunha et al., 2012).