Digestibility in Lactating Cows of Diets Containing Whole Pima Treated with Sodium Hydroxide Versus Akala or Pima Cottonseed

Novel Process Methods for the Whole Cottonseed: Effect on the Digestibility, Productivity, Fat Profile, and Milk Gossypol Levels in Lactating Dairy Cows

In this study, we aimed to determine the effect of mixed-process methods on the ruminal degradability of whole cottonseed (WCS) both in situ and in vitro, and the effect on the production performance of dairy cows. Eight WCS process methods were tested on the ruminal digestibility, including crush-alkali 1 (CA1), crush-alkali 2 (CA2), crush-alkali 3 (CA3), alkali 1-crush (A1C), alkali 2-crush (A2C), alkali 3-crush (A3C), crush-only (CO), and non-processed. Alkali 1, 2, and 3 indicate the supplementation of alkali to WCS at the dose of 4% on dry matter (DM) base as followed: 4% NaOH, 2% NaOH + 2% CaO, and 2% NaOH + 2% CaCl₂ alkaline, respectively. Among all treatments, CA2 showed the highest WCS ruminal degradation in situ and the highest intestinal digestibility of WCS in vitro. Furthermore, an animal experiment was conducted for 60 days on 30 Holstein dairy cows, using a diet without WCS (CON group), a diet containing 8% non-processed WCS (NP group), and a diet containing 8% CA2-treated WCS (CA2 group). The results indicated that the dry matter intake, 4% fat-corrected milk production, milk protein, milk fat, and content of short-chain saturated fatty acid of milk in the CA2 group were significantly higher (P < 0.05) than CON group. Furthermore, DMI, the CLA was significantly greater (P < 0.05) in the CA2 group than the other groups. Additionally, the free gossypol concentration in serum or milk was under safety level in the three groups. Overall, crush and alkalization (NaOH: CaO = 1:1) treatment could improve the utilization of WCS in dairy farms.

Heat production and retained energy in lactating cows held under hot summer conditions with evaporative cooling and fed two rations differing in roughage content and in vitro digestibility

The objective of this study was to measure the effect of feeding two total mixed rations (TMRs), differing in their roughage content and in vitro dry matter (DM) digestibility, on the physiological response and energy balance of lactating cows. The partitioning of metabolizable energy intake (MEI) between heat production (HP) and retained energy (RE) of cows held under hot weather conditions and external evaporative cooling was measured. In all, 42 lactating cows were divided into two similar sub-groups, each of 21 animals, and were fed either a control (CON) ration containing 18% roughage neutral detergent fiber (NDF) or an experimental (EXP) TMR containing 12% roughage NDF and used soy hulls as partial wheat silage replacer. The in vitro DM digestibility of the CON and EXP TMR was 75.3% and 78.6%, respectively (P < 0.05). All cows were cooled by evaporative cooling for 2 adaptation weeks plus 6 experimental weeks under hot weather conditions. The EXP diet reduced rectal temperature and respiratory rate of the cows while increasing their DM intake (DMI) from 23.1 to 24.7 kg/cow per day, milk yield from 41.9 to 44.2 kg and yield of energy-corrected milk from 38.7 to 39.7 kg, as compared with the CON group. Cows fed the EXP TMR had increased RE in milk and body tissue, as compared with the CON group, but the diets had no effect on the measured HP that was maintained constant (130.4 v. 130.8 MJ/cow per day) in the two groups. The measured MEI (MEI = RE + HP) and the efficiency of MEI utilization for RE production were also similar in the two dietary groups.

Processing Whole Cottonseed Moderates Fatty Acid Metabolism and Improves Performance by Dairy Cows

Pelleting cottonseed (CS) improves handling characteristics. Our objectives were to determine whether increasing the particle size of the CS pellet or dilution of a smaller pellet with delinted CS would limit the rate of CS oil release to optimize digestibility of fatty acids (FA) and fiber while maintaining milk fat production. In a 5 x 5 Latin square design with 3-wk periods, 5 rumen-cannulated cows were fed 1) control with CS hulls (CSH) and CS meal plus tallow and Ca soaps of FA, 2) whole CS (WCS), 3) small CS pellets (SP; 0.44-cm die diameter), 4) larger CS pellets (LP; 0.52-cm die diameter), or 5) a blend of 1/2 SP plus 1/2 partially delinted CS (SPD). Diets contained 39.6% concentrate, 14.4% CS, and 46% forage (40:60, alfalfa hay:corn silage) on a DM basis and were balanced to have similar concentrations of CS protein, CS fiber, and total fat. In a production trial, dietary treatments were 1) WCS control, 2) LP, 3) SPD, and 4) SPD fed at 90%. Sixty cows averaging 105 d in milk were fed the WCS diet for 2 wk and then assigned to one of the 4 diets for 12 wk. Total tract digestibility of NDF was unaffected, but N digestibility was lower for SPD than for other treatments. Fatty acid digestibility was higher for SP and LP (82.6 and 82.3%) than for CSH or SPD treatments (78.8 and 75.3%), and WCS was intermediate (81.1%). The trans-11 C18:1 from cows fed SP and LP (6.58 and 6.24% of total milk FA) was greater than that from cows fed CSH, WCS, and SPD (3.23, 3.79, and 3.97%). The trans-10 C18:1 in milk fat from SP and LP (0.508 and 0.511%) was higher than that in WCS and SPD diets (0.316 and 0.295%); CSH was intermediate (0.429%). Using passage rates estimated from the NRC, disappearance of total FA in situ was estimated to be 17.7, 44.2, 46.6, and 35.0% for WCS, SP, LP, and SPD, respectively. In the production trial, a diet x week interaction was explained by a trend for progressively greater milk production for SPD and SPD90 than for WCS or LP. Milk fat was lower for LP (2.74%) and SPD90 (2.85%) than for WCS or SPD (3.07 and 3.08%). The fat yield was lower for LP than for SPD (1.09 and 1.30 kg/d); WCS and SPD90 were intermediate (1.23 and 1.21 kg/d). Although having a lower FA digestibility, SPD appeared to minimize negative effects of free oil from SP in the rumen, explaining higher DMI and milk production compared with WCS or LP.