Cottonseed and Gossypol: Effects on Lactation, Reproduction and Health J.E.P. Santos, 1 E.J. DePeters, 2 and P.H. Robinson 2 1 Veterinary Medicine Teaching and Research Center 2 Department of Animal Science University of California - Davis

Cottonseed and Gossypol Cottonseed is generally fed at 10 to 15% of the diet Provides a unique blend of protein, fat and fiber for inclusion in diets of dairy cows Cottonseed contains gossypol (0.5 to 1.2%), which is a toxin present throughout the cotton plant that helps to control pests However, gossypol can be toxic to mammals and it disrupts reproduction in males

Gossypol Mixture of two stereoisomers: (+) and (-) gossypol – –The (-) isomer is thought to be more toxic and retained in the body longer Gossypol can be found in the free or bound forms – –Free gossypol is assumed to be available for absorption in the digestive tract

Gossypol Fact: – –Gossypol is extremely toxic to non-ruminant animals and to young ruminants at small quantities in the diet – –Ability to tolerate gossypol coincides with development of rumen functions – –Affects fertility in males Dogma : – –Any gossypol is bad for lactating dairy cows – –The upper safe level of plasma gossypol is  5  g/ml

Gossypol First discovered in China Until 1980’s little attention was given to gossypol as a toxin in cattle diets: – –Classic work by Holmberg and colleagues in 1988 at UC Davis characterizing the pathological effects of gossypol in calves fed cottonseed meal

Cottonseed & Gossypol Substantial amount of published literature on the effects of cottonseed and gossypol on lactation performance of dairy cows: – –Different types of cottonseed, different levels cottonseed in the diets, different concentrations of gossypol in the diet, different sources of gossypol in the diet, short-term and long-term studies, etc. Very limited data available on the effects of cottonseed and gossypol on reproductive functions in female cattle: – –Few studies with limited number of animals and some studies utilizing in vitro techniques to replicate reproductive processes in female bovine.

Cottonseed & Gossypol One method to study the effects of gossypol on cattle is to use cottonseeds with different gossypol concentrations or compare cottonseed with cottonseed meal: – –Whole Upland vs Pima cottonseed Slightly different in nutrient composition (lack of lint), but extremely different in gossypol content – –Cottonseed vs Cottonseed Meal Differ in availability of gossypol

Mena et al. (1997) Effect of Type of Cottonseed on FG Intake and Plasma TG in Steers Type of Cottonseed WholeCrackedExtruRoast CrRoastSEM DMI, kg/d FG intake g/d10.3 a 10.0 a 1.7 c 3.8 b 1.4 c 0.32 mg/kg BW26.8 a 25.6 a 4.0 c 10.3 b 4.1 c 0.80 Plasma TG1.19 a 1.43 a 0.75 b 0.81 b 0.18 c 0.10

Prieto et al. (2002) Ratio of Whole Upland and Cracked Pima 100:067:3333:670:100 SEMLinear Mature TG, g/d DMI, lb/d Milk, lb/d Heifers TG, g/d DMI, lb/d Milk, lb/d

Effect of Type of Cottonseed and Iron Sulfate on Plasma TG in Dairy Cows ( et al., 2002) Effect of Type of Cottonseed and Iron Sulfate on Plasma TG in Dairy Cows (McCaughey et al., 2002) Cottonseed: P < 0.01 Iron sulfate: P < 0.01

McCaughey et al. (2002) Effect of Type of Cottonseed and Fe Sulfate on Performance of Lactating Dairy Cows WUPCrP:WUP Iron Sulfate Linear DMI, kg/d Multiparous Primiparous Milk, kg/d Multiparous Primiparous

Plasma gossypol (PG) concentrations in lactating dairy cows fed varying amounts of gossypol from whole cottonseed and cottonseed meal. Solid triangle (  ) = control (0 mg/kg); Open square (  ) = 1040 mg/kg total gossypol (TG) from whole cottonseed (WCS); Open circle (  ) = 900 mg/kg TG from cottonseed meal (CSM); Solid circle (  ) = 960 mg/kg TG, half from WCS and half from CSM; Solid square (  ) = 1922 mg/kg TG, half from WCS and half from CSM (Mena et al., 2001)

Mena et al. (2001) Effect of Source of Gossypol on Performance of Dairy Cows Diet TG, ppm SEM DMI, kg/d FG intake g/d0.0 c 22.4 a 1.5 c 12.1 b 25.2 a 1.00 mg/kg BW0.0 c 33.8 a 2.2 c 18.1 b 38.0 a 1.66 PTG, ug/ml0.22 d 2.94 b 0.77 cd 1.63 c 4.96 a 0.37 Milk, kg/d27.6 b 29.7 ab 27.9 b 28.7 b 32.6 a 1.4 FCM, kg/d25.4 c 28.2 ab 25.3 c 27.4 bc 30.2 a 1.3

Relationship between free gossypol (FG) intake (g/d) and plasma gossypol (PG) concentration (  g/ml) in lactating dairy cows after 42 days of feeding diets varying in gossypol content (Mena et al., 2001). Plasma gossypol = FG r 2 = 0.80

Filed Study in California Study: – –813 lactating Holstein cows in 3 commercial dairies – –10 pens (5/treatment) – –406 cows/trt – –Low vs high gossypol diet (750 vs 990 mg/kg FG) – –Cows were fed for the first 183 DIM – –Production, reproduction and health were monitored

Experimental Protocol Diets: 10% WUP vs 10% of a 1:2 blend of WUP & cracked Pima 813 cows day postpartum D PP30 ± 344 ± 363 ± 393 ± 3183 BCSPGF Blood + BCS BCS Heat detection & AI Pregnancy Diagnosis

Nutrient Composition of Diets Cottonseed ItemWUPBWUPCPSEMP < Samples, n 15 OM, % NE L, Mcal/lb CP, % Fat, % ADF, % NDF, % TG, mg/kg 7431,000 Santos et al. (2002)

Effect of Type of Cottonseed on Performance of Dairy Cows Cottonseed ItemWUPBWUPCPSEMP < Cows, n DMI, lb/d FG, g/d Milk, lb/d % FCM, lb/d Santos et al. (2002)

Association of plasma TG above or below the mean on yields of milk and milk components Plasma TG ItemAbove MeanBelow MeanTGTRT x TG Cows, n Milk, lb/d % FCM, lb/d Milk fat, lb/d Milk protein, lb/d Santos et al. (2002)

Plasma Total Gossypol in Primiparous and Multiparous Cows Fed WUP or a Blend of WUP and Cracked Pima Santos et al. (2002)

Effect of Type of Cottonseed and Gossypol Intake on Conception and Pregnancy Rates of Lactatin Dairy Cows P < 0.72 P < 0.01 Santos et al. (2002)

Effect of Type of Cottonseed and Gossypol Intake on Days Open in Lactating Dairy Cows Whole Upland: Blend of cracked Pima and WUP: Cottonseed: P < 0.01

Plasma Gossypol Concentration in Lactating Dairy Cows P < 0.01 P < 0.04 Santos et al. (2002)

Effect of Plasma Total Gossypol Above or Below the Mean on Days Open in Lactating Dairy Cows TG: P < 0.04 Above Mean: Below Mean:

P < 0.05 Effect of Plasma Gossypol Concentrations on Days Open in Dairy Cows

Effect of Type of Cottonseed and Gossypol Intake on Conception Rate of Dairy Cows (1,863 AI) (Santos et al. 2002) Cottonseed: P < 0.03 Plasma Gossypol: P < 0.01

Effect of Type of Cottonseed and Gossypol Intake on Incidence of Health Disorders in Lactating Dairy Cows Treatment Item WUPBlend WUP and CrP P < Mastitis, % DIM at first mastitis Lameness, % DIM at first lameness Any health disorder, % Death and culling, % Santos et al. (2002)

Take Home Message Cottonseed can be safely fed to lactating dairy cows at 10 to 15% of the diet DM with minimum effects on lactation performance Small amounts of gossypol can disrupt fertility in bulls – –Consider AI vs bull breeding There is no clear evidence that dietary gossypol up to 1,000 mg/kg of diet affects lactation or health of lactating dairy cows High gossypol diets for extended periods increases plasma TG and can affect conception and pregnancy maintenance in dairy cows

Acknowledgements SUPIMA Association of America Cotton Incorporated Dairy owners and their staff