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Abstract:Using the 4th Tank Battalion as a case study, this article argues that U.S. Marine tankers in World War II possessed a uniquely American mechanical aptitude that allowed them to make necessary modifications to their tanks that were crucial to combat effectiveness in the Pacific. Having grown up during the Great Depression and possessing a "use it up, wear it out, make it do, or do without," mentality, these tankers recognized what could be done to improve their tanks, and applying American ingenuity, fabricated armor and tank-to-infantry communications systems, among other innovations to enhance their abilities as warfighters. While this trait was not necessarily unique to the 4th Tank Battalion, their leaders, Captain Robert M. Neiman and Lieutenant Henry L. Bellmon in particular, encouraged such activity, and the battalion was certainly among the most mechanically creative among the Marine tank battalions in the Pacific.

Angus X Hereford heifers were used to evaluate the effect of prenatal nutritional restriction on postnatal growth and development. Fifteen month-old heifers were inseminated with semen from an Angus bull. At 32.0 ± 0.5 d after insemination, pregnancy was verified and heifers were stratified by weight and body condition score (BCS) and allotted to low (L, n=10, fed 55 % of NRC 1996 requirements) or moderate nutrition (M, n=10, fed above NRC 1996 requirements). After 83 d of treatment (115 d of gestation) heifers were comingled and received a common diet in excess of NRC requirements. Male calves were castrated at birth and weaned at approximately 230 d of age. Calves were maintained as a group after weaning. At 16 mo of age, L (n=5) and M (n=5) steers were fed a high concentrate diet to gain 2.3 kg/d to a body weight of 550 kg. Steers were harvested and weights of the empty body, heart, lungs and trachea, spleen, kidney, liver, pancreas, and the gastrointestinal tract were recorded. Samples of the heart and muscle (Complexus) were stored at −80° C and DNA in tissue was quantified using Hoechst H33258dye. All growth data were analyzed with the GLM procedure of SAS and amount of DNA per tissue was analyzed with the PROC MIXED procedure of SAS. Body weight and BCS were similar for L and M heifers at treatment (average = 385 ± 7 kg; 5.0 ± 0.1 BCS). At the end of treatment, L heifers weighed less (328 ± 6 kg) and had less BCS (4.3 ± 0.01) compared with M heifers (424 ±10 kg, 5.5 ± 0.1 BCS). Length of gestation was 274 ± 2 d for L heifers and 278 ± 2 d (P = 0.05) for M heifers. Treatment did not influence birth weight or growth of steer calves until harvest. Lungs and trachea of steers exposed to L prenatal nutrition weighed less ( P = 0.05, 5.30 ± 0.55 kg) compared with M steers (6.35 ± 0.78 kg); weights of other tissues were not influenced by treatment. Weight of carcass and amount of 12th-rib subcutaneous fat were not influenced by treatment. Muscle from L steers had greater (P = 0.04) DNA per gram of tissue than M steers (0.58 ± 0.02 vs 0.52 ± 0.1 mg/g, respectively). DNA concentrations and content in the heart were not influenced by treatment. Nutritional restriction of the bovine during early gestation did not alter postnatal growth rate: however, concentrations of DNA in muscle tissue at maturity were greater in restricted animals. (poster)