Patrick C. Hoffman

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Criteria that define optimum body size of replacement heifers are required by commercial dairy producers to evaluate replacement heifer management programs. Historically recommended body size criteria have been based on live BW measurements. Numerous research studies have observed a positive relationship between BW at first calving and first lactation milk(More)
A study was conducted to evaluate the effect of limit feeding on growth, feed efficiency, and manure excretion in Holstein heifers and subsequent milk production. Fifty-four gravid Holstein heifers were randomly assigned to replicate pens and fed 1 of 3 experimental diets for 111 d. Experimental diets included an ad libitum-fed control diet containing 11.3%(More)
Eight forages (alfalfa, birdsfoot trefoil, red clover, bromegrass, orchardgrass, perennial ryegrass, quackgrass, and timothy) at three maturities were evaluated for ruminal DM, CP, and NDF degradation kinetics. Duplicate dacron bags were incubated for 0, 3, 6, 10, 13, 25, 48, and 72 h in two late lactation Holstein cows fitted with ruminal cannulas over(More)
Starch supplied from corn grain or corn silage is an important source of dietary energy for lactating dairy cows and other ruminants, but few laboratory methods are available to determine starch digestion potential. A laboratory method, degree of starch gelatinization (DSG), commonly used by the food industry to assess relative differences in starch(More)
Seventy postpubertal Holstein replacement heifers were assigned to one of four treatments to assess effects of accelerated postpubertal growth on performance during first lactation. Heifers were fed control or accelerated diets from 10 mo of age until parturition, and breeding was initiated at 14 or 10 mo of age, respectively. Heifers were also subdivided(More)
Differences in conception rates in matings of Holstein sires or F1 Jersey x Holstein sires to Holstein dams in the University of Wisconsin-Madison experimental herd were evaluated, as were differences in birth weight, dystocia, serum protein, serum IgG, fecal consistency, respiratory disease, and perinatal and pre-weaning mortality among the resulting(More)
The fates of hydrophobic zein proteins, which encapsulate corn starch to create vitreous endosperm, have not been investigated in high-moisture corn (HMC). To assess influences of ensiling time and inoculation on zein proteins in HMC, quadruplicate samples of 2 random corn hybrids (A and B), containing 25.7 and 29.3% moisture, were ground, inoculated with(More)
A growth study and a companion N balance study were conducted to evaluate the effect of dietary protein on growth and N utilization of postpubertal Holstein heifers. Forty heifers (398 +/- 9.4 kg) were fed one of four diets containing 8, 11, 13, or 15% crude protein (CP) for 121 d. Body measurements were taken at the beginning and end of the experimental(More)
Sixty-seven Holstein replacement heifers (19 mo) were fed a standard (59.7% TDN) or a high energy (69.3% TDN) diet until parturition. After parturition, primiparous cows were fed either 0 or 2.8% supplemental tallow for 150 d in a 2 x 2 factorial arrangement with prepartum treatments. High energy prepartum increased BW (693.5 vs. 663.7 kg) and body(More)
The nutrient contents of perennial ryegrass (Lolium perenne L.) and alfalfa (Medicago sativa L.) are reasonably similar. Despite similarities, the lactation performance of dairy cows fed perennial ryegrass has not been compared with the lactation performance of dairy cows fed alfalfa. The present study was implemented to compare the performance of lactating(More)