title: Effect of feeding various levels of sodium zeolite A on milk yield, milk composition and blood profiles in thermally stressed Holstein cows.
abstract: Mid-lactation Holstein cows (n = 48) were equally and randomly assigned to one of four feeding treatments of sodium zeolite-A (SZA). SZA was mixed in a grain mixture (50:50 grain to forage ratio) of 0% (control), 0.5%, 1.0% and 1.5% SZA on a dry matter intake basis. Cows were fed alfalfa hay in the first phase and corn silage in the second phase of the study as roughage sources. Milk samples were taken three times weekly (am and pm) and analyzed for milk fat, protein and lactose with blood profiles conducted from samples collected weekly. SZA significantly (P less than .05) increased feed intake at all three levels for both diets. Milk yield was significantly (P less than .05) greater in the alfalfa diet. However, milk fat percent and percent protein were greater (P less than .05) in the corn silage diet. The addition of SZA to the corn silage diet increased (P less than .05) milk fat percent at the 1.0% level and milk protein at the 1.5% level. Calcium in milk was significantly (P less than .01) increased and respiration rates significantly lowered (P less than .05) in both diets at the 1.0% level. Serum calcium was higher (P less than .05) at the 1.0 and 1.5% level in the hay diet and the 1.5% level in the corn silage diet. Also, serum glucose and alkaline phosphate levels were significantly (P less than .05) higher in the corn silage diet.
authors.affiliation: Department of Dairy Science, Louisiana State University, Baton Rouge 70803.
authors.forename: J D
authors.initials: JD
authors.lastname: Roussel
authors.forename: J K
authors.initials: JK
authors.lastname: Thibodeaux
authors.forename: R W
authors.initials: RW
authors.lastname: Adkinson
authors.forename: G M
authors.initials: GM
authors.lastname: Toups
authors.forename: L L
authors.initials: LL
authors.lastname: Goodeaux
mesh_terms: D000538:Aluminum Silicates / Q000008:administration & dosage* / Q000097:blood; D000818:Animals; D002118:Calcium / Q000097:blood; D002417:Cattle / Q000378:metabolism*; D004032:Diet; D004043:Dietary Fiber / Q000032:analysis; D004435:Eating; D005260:Female; D006358:Hot Temperature; D007774:Lactation / Q000187:drug effects; D000455:Medicago sativa; D008892:Milk / Q000032:analysis / Q000187:drug effects*; D010758:Phosphorus / Q000097:blood; D012820:Silage; D013312:Stress, Physiological / Q000097:blood / Q000378:metabolism*; D003313:Zea mays; D017641:Zeolites
chemical_list: D000538:Aluminum Silicates; D004043:Dietary Fiber; D017641:Zeolites; D010758:Phosphorus; D002118:Calcium