Effects of Feeding Rations with Genetically Modified Whole Cottonseed to Lactating Holstein Cows

Abstract

Two experiments were conducted to evaluate dry matter intake (DMI), milk yield, and milk composition from feeding rations that contained different sources of genetically modified whole cottonseed to Argentinean Holstein dairy cows. Twenty-four lactating multiparous Argentinean Holstein dairy cows were used in 2 experiments with a replicated 4 x 4 Latin square design, with cows averaging 565 kg body weight and 53 d in milk at the beginning of the experiments. Treatments in Experiment 1 were: Bollgard cotton containing the cry1Ac gene, Bollgard II cotton containing cry1Ac and cry2Ab genes, Roundup Ready cotton containing the cp4 epsps gene, and a control nongenetically modified but genetically similar cottonseed. In Experiment 2, two commercial sources, a parental control line, and the transgenic cotton containing both cry1Ac and cp4 epsps genes were used as treatments. All cows received the same total mixed ration but with different whole cottonseed sources. Cottonseed was included to provide 2.50 kg per cow daily (dry matter [DM] basis) or about 10% of the total diet DM. The ingredient composition of the total mixed ration was 32% alfalfa hay, 28% corn silage, 22% corn grain, 17% soybean meal, and 2% minerals and vitamins. In addition, genomic DNA was extracted from a subset of milk samples and analyzed by polymerase chain reaction followed by Southern blot hybridization for small fragments of the cry1Ac transgene and an endogenous cotton gene, acp1. No sample was positive for transgenic or plant DNA fragments at the limits of detection for the assays following detailed data evaluation criteria. The DMI, milk yield, milk composition, body weight, and body condition score did not differ among treatments. Cottonseed from genetically modified varieties used in these studies yielded similar performance in lactating dairy cows when compared to non-transgenic control and reference cottonseed.

Feed intake, milk production and composition of crossbred cows fed with insect-protected Bollgard II® cottonseed containing Cry1Ac and Cry2Ab proteins

“…Nutrient content of maize forage was similar to values reported by Sen and Ray (1977). The DMI in this study was similar to a previous study in which crossbred lactating cows consumed a Bt (Cry1Ac) cottonseed-based ration (Singhal et al, 2006) and also in an experiment in which cows consumed cottonseed containing both Cry1Ac and Cry2Ab (Castillo et al, 2004). The higher NDF intake as the percentage of total DM intake in both groups than the level (37%) recommended by NRC (2001), as well as Mertens (1985) for cows yielding 16 to 24 kg FCM daily, could be attributed to the tropical conditions, which increases the cell wall fractions in feeds and fodder.…”

“…In India, the safety of Bt cottonseed having Cry1Ab was evaluated earlier in cattle (Singhal et al, 2006). Feeding of Bt cottonseed (Cry1Ab protein) has been shown to be safe in lactating dairy cows (Castillo et al, 2004;Singhal et al, 2006). Performance and health of lactating dairy cows in Argentina fed BGII cottonseed were found to be not different from cows fed conventional non-genetically modified (GM) cottonseed (Castillo et al, 2004).…”

“…Feeding of Bt cottonseed (Cry1Ab protein) has been shown to be safe in lactating dairy cows (Castillo et al, 2004;Singhal et al, 2006). Performance and health of lactating dairy cows in Argentina fed BGII cottonseed were found to be not different from cows fed conventional non-genetically modified (GM) cottonseed (Castillo et al, 2004). The objectives of this research were to evaluate the effects of BGII cottonseed on dry matter intake (DMI), milk yield and milk composition and to measure Cry1Ab and Cry2Ac proteins in milk and blood of Indian crossbred cows fed BGII and a conventional cottonseed.…”

Effect of Bt-cottonseed meal feeding on performance, fermentation, ciliates population and microbial hydrolytic enzymes in lamb

“…Both cottonseeds used in this study were grown in India under identical agronomic and environmental conditions, thereby eliminating nutrient differences. Transgenic cotton crop containing different genes or gene combinations did not differ in nutrient composition (Castillo et al, 2004). Differences in chemical constituents and anti-nutritional content were also not found (Hawkins et al, 1985;Kumar and Singhal, 2004) in whole seed and defatted meal between Bt and non-Bt cotton grown in India.…”

Safety Evaluation of Bt Plants

“…Other feeding studies also demonstrated the equivalence of nutritional value of Bt corn and productivity of animal products from cattle fed Bt corn, compared with its nontransgenic control 18,23,58 . Additionally, the results of some compositional analyses and feeding studies of Bt cotton indicated that transgenic cotton is substantially equivalent to its non-transgenic control, similar to Bt corn 8,25 .…”