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Biomedical subjects

R J Grant

Publications and source records attributed to R J Grant.

At least 37 records · Page 2Linked to original sources
PubMed1999

Brown midrib sorghum in diets for lactating dairy cows.

In Experiment 1, 16 Holstein cows were assigned to one of four diets in replicated 4 x 4 Latin squares with 4-wk periods to measure dietary effect on short-term lactational performance. Additionally, 3 fistulated cows were assigned to the same diets in a 3 x 4 Youden square design with 4-wk periods to measure ruminal rate and extent of fiber digestion, fractional passage rate of fiber, ruminal pH, and concentration of volatile fatty acids. Diets comprised 65% of brown midrib (BMR) forage sorghum, standard forage sorghum, alfalfa or corn silages and 35% concentrate. Experiment 2 was conducted with 30 Holstein cows in early lactation to evaluate the same BMR sorghum hybrid in a 10-wk study with 35.3% standard sorghum, BMR sorghum, or corn silages as dietary treatments. Milk production was significantly higher for brown midrib than for standard sorghum in Experiment 1. Ruminal pH and acetate to propionate ratio did not differ among diets. The fractional passage rate of silage was not significantly different among the forages. In situ extent of ruminal fiber digestion was significantly higher for BMR than for standard sorghum, but rate of fiber digestion was not different. Similarly, in Experiment 2, in vitro extent of fiber digestion was significantly higher for BMR sorghum than for standard sorghum. Dry matter intake and body condition score were not significantly different between cows fed BMR and standard sorghum, but cows fed BMR sorghum resulted in long-term milk production greater than cows fed standard sorghum and similar to cows fed corn silage.

Animals↗
PubMed1998

Adherence of the gram-positive bacterium Ruminococcus albus to cellulose and identification of a novel form of cellulose-binding protein which belongs to the Pil family of proteins.

The adherence of Ruminococcus albus 8 to crystalline cellulose was studied, and an affinity-based assay was also used to identify candidate cellulose-binding protein(s). Bacterial adherence in cellulose-binding assays was significantly increased by the inclusion of either ruminal fluid or micromolar concentrations of both phenylacetic and phenylpropionic acids in the growth medium, and the addition of carboxymethylcellulose (CMC) to assays decreased the adherence of the bacterium to cellulose. A cellulose-binding protein with an estimated molecular mass following sodium dodecyl sulfate-polyacrylamide gel electrophoresis of approximately 21 kDa, designated CbpC, was present in both cellobiose- and cellulose-grown cultures, and the relative abundance of this protein increased in response to growth on cellulose. Addition of 0.1% (wt/vol) CMC to the binding assays had an inhibitory effect on CbpC binding to cellulose, consistent with the notion that CbpC plays a role in bacterial attachment to cellulose. The nucleotide sequence of the cbpC gene was determined by a combination of reverse genetics and genomic walking procedures. The cbpC gene encodes a protein of 169 amino acids with a calculated molecular mass of 17,655 Da. The amino-terminal third of the CbpC protein possesses the motif characteristic of the Pil family of proteins, which are most commonly involved with the formation of type 4 fimbriae and other surface-associated protein complexes in gram-negative, pathogenic bacteria. The remainder of the predicted CbpC sequence was found to have significant identity with 72- and 75-amino-acid motifs tandemly repeated in the 190-kDa surface antigen protein of Rickettsia spp., as well as one of the major capsid glycoproteins of the Chlorella virus PBCV-1. Northern blot analysis showed that phenylpropionic acid and ruminal fluid increase cbpC mRNA abundance in cellobiose-grown cells. These results suggest that CbpC is a novel cellulose-binding protein that may be involved in adherence of R. albus to substrate and extends understanding of the distribution of the Pil family of proteins in gram-positive bacteria.

Adhesins, Bacterial↗
PubMed1998

Effect of soybean hulls, soy lecithin, and soapstock mixtures on ruminal fermentation and milk composition in dairy cows.

Two experiments were conducted to determine effects of soybean hulls, soy lecithin, and soapstock mixtures on ruminal fermentation, milk composition, and ruminal microbial populations. In Experiment 1, 20 Holstein dairy cows were assigned to one of five total mixed rations (TMR) in replicated 5 x 5 Latin squares to measure the effect of TMR on intake and milk composition. Four ruminally fistulated cows were used in a 4 x 5 Youden square to measure the effect of TMR on ruminal fermentation. The TMR consisted of 40 or 50% alfalfa and corn silages, 13% soybean hulls, and 47 or 37% of a concentrate containing either 2.25% soybean oil; 2.25% lipid from a mixture of soybean hulls, soy lecithin, and soapstock; or no added lipid. The ratios of soy lecithin to soapstock evaluated were 1:1, 2.5:1, and 4:1 (dry basis). The TMR containing soy lecithin and soapstock at ratios of 1:1 and 2.5:1 resulted in higher milk C18:2 than did the soybean oil TMR. Rate of ruminal NDF digestion of soybean hulls was reduced for the soybean oil TMR. In Experiment 2, a semi-continuous culture system was used to determine effects of soybean oil or an optimal mixture of soy lecithin and soapstock (1:1, wt/wt) on fermentation of soybean hulls and microbial populations. The TMR containing the lipid mixture increased the ratio of acetate to propionate compared with the TMR containing soybean oil and resulted in higher total protozoal counts than did the control TMR. The TMR containing mixtures of soy lecithin and soapstock at ratios of 1:1 and 2.5:1 elevated milk C18:2, and no negative effect on NDF digestion was detected, indicating some degree of ruminal protection.

Animal Feed↗
PubMed1998

Influence of nonenzymatically browned soybeans on ruminal fermentation and lactational performance of dairy cows.

Four ruminally fistulated Holstein cows were assigned to one of four total mixed rations (TMR) in a 4 x 4 Latin square with 3-wk periods to investigate the effects of added lipid from nonenzymatically browned soybeans or soybean oil on ruminal metabolism and milk fatty acids. All rations contained 50% forage and 1) 4% added lipid from soybean oil, 2) 4 or 6% added lipid from nonenzymatically browned soybeans, or 3) no added lipid (control). The TMR that contained nonenzymatically browned soybeans increased milk C18:2 by 35% compared with the TMR that contained soybean oil. A lactation trial was conducted in which 60 Holstein cows were assigned to one of five TMR from wk 3 to 18 of lactation. The TMR contained 1) 4.5% added lipid from soybean oil, 2) 1.5% added lipid from nonenzymatically browned soybeans and 3% from soybean oil, 3) 3% added lipid from nonenzymatically browned soybeans and 1.5% from soybean oil, 4) 4.5% added lipid from nonenzymatically browned soybeans, and 5) 4.5% added lipid from Ca salts of long-chain fatty acids. Dry matter intake was reduced by 11% for cows fed the TMR containing soybean oil only compared with that for cows fed the other TMR. Milk C18:2 and C18:3 were increased as the inclusion of nonenzymatically browned soybeans in the TMR increased. All percentages of the nonenzymatically browned soybeans fed to cows resulted in fat-corrected milk yields that were similar to those of cows fed the TMR that contained Ca salts of fatty acids.

Animals↗
PubMed1998

Effect of a mixture of feather and blood meals on lactational performance of dairy cows.

An experiment was conducted over 18 wk of lactation to determine the effect of supplemental feather and blood meals (85:15, wt/wt, dry matter basis) fed at two dietary concentrations of crude protein (CP) on dry matter intake and milk protein production. Forty-eight Holstein cows were grouped by parity and assigned randomly at 3 wk postpartum to one of four diets following a 2-wk covariate period. Diets consisted of 50% alfalfa silage and 1) no feather or blood meals, 17.6% CP, and 5.1% ruminally undegradable protein (RUP); 2) 4% mixture of feather and blood meals, 17.6% CP, and 6.3% RUP; 3) no feather or blood meals, 19.6% CP, and 6.3% RUP; and 4) 4% mixture of feather and blood meals, 19.6% CP, and 6.9% RUP. According to the National Research Council, diet 1 was deficient in RUP, diets 2 and 3 were adequate in RUP, and diet 4 contained excessive CP and RUP. Intakes of dry matter and CP were depressed by 11% for cows fed the 19.6% CP diet supplemented with feather and blood meals. For cows fed the 17.6% CP diet, the supplementation of feather and blood meals increased RUP intake, but the supplementation of feather and blood meals to the 19.6% CP diet had no effect on RUP intake. Supplemental feather and blood meals increased the production of milk protein and 3.5% solids-corrected milk by cows fed the 17.6% CP diet. Diets 2, 3, and 4 resulted in similar efficiencies of solids-corrected milk production, but the efficiency of milk protein production specifically was increased by the supplementation of feather and blood meals to the 17.6% CP diet only. Results of this experiment indicate that a mixture of feather and blood meals improves the production of milk protein when supplemented to a diet that meets, but does not greatly exceed, the requirements established by the National Research Council for RUP and that contains alfalfa as the sole forage.

Animal Feed↗
PubMed1998

Effect of wheat straw treated with alkali on ruminal function and lactational performance of dairy cows.

Two experiments were conducted to evaluate the effects of wheat straw treated with alkali on ruminal function and lactational performance of dairy cows. In Experiment 1, four ruminally fistulated Holsteins cows (X = 57 d of lactation) were fed four diets that contained 0, 20, 30, or 40% (dry basis) wheat straw treated with 3% NaOH plus 3% Ca(OH)2 in a 4 x 4 Latin square. The diets contained 60, 40, 30, and 20% (dry basis) prebloom alfalfa haylage to result in a 60: 40 ratio of forage to concentrate. In Experiment 2, 12 (X = 149 d of lactation) midlactation Holstein cows were fed diets containing 0 or 20% treated wheat straw to measure lactational performance during a 12-wk period. In Experiment 1, no effect of diet was observed on ruminal pH, osmolality, digestion of neutral detergent fiber of straw, or 4% fat-corrected milk. However, the dry matter intake of cows fed diets containing the two highest concentrations of treated straw was depressed and was associated with a significant body weight loss. The ruminal rate of passage of treated straw was not affected by diet; however, rate of passage of alfalfa haylage decreased when straw was included in the diet. In Experiment 2, no effect on cow performance was observed when straw treated with alkali was included at 20% of the diet. Inclusion of up to 20% wheat straw treated with 3% NaOH plus 3% Ca(OH)2 in diets of lactating cows resulted in ruminal function and performance that were similar to those of cows fed diets that contained alfalfa haylage only.

Animal Nutritional Physiological Phenomena↗
PubMed1998

Are critically ill older patients treated differently than similarly ill younger patients?

Our goal was to determine whether critically ill older patients are treated differently than middle-aged patients. If so, what factors besides age contribute to that difference? Internal medicine residents (n = 46) and practicing internists (n = 41) received 8 clinical vignettes of 4 critically ill 85-year-old patients and 4 critically ill 50-year-old patients. Each patient had a distinct premorbid mental and physical state. Each respondent selected from 4 levels of therapeutic aggressiveness for each patient. The main outcome measure was the proportion of physicians who intended to treat the older of each matched pair of patients less aggressively than the younger one (that is, downgraded for age). Eight physicians (9%) treated a previously unimpaired 85-year-old patient less aggressively than a comparable 50-year-old patient. When the matched patients were either premorbidly mentally or physically impaired (but not both), about 20% of physicians downgraded for age. Most downgraded for age in matched patients who were premorbidly both mentally and physically impaired. We conclude that age alone does not engender much therapeutic bias against older patients as long as they are physically and mentally intact before the onset of their acute illness. As premorbid disabilities multiply, older patients may be treated less aggressively than younger ones with similar impairments and clinical presentations.

Age Factors↗
PubMed1997

Relationships between in situ protein degradability and grass developmental morphology.

The objective of this research was to determine the relationships between the morphological development and in situ ruminally degradable protein (RDP), ruminally undegradable protein (RUP), and microbial protein of two cool season grasses (intermediate wheatgrass and smooth bromegrass) and two warm season grasses (switchgrass and big bluestem). The initial growth of grass tillers grown near Mead, Nebraska was clipped at ground level six times during the 1992 growing season and morphologically classified. Mean stage was calculated. Forage was ground to pass a 2-mm screen and was incubated in ruminally fistulated steers for 16 h. The RUP was adjusted for microbial protein and acid detergent insoluble N. The mean stage of cool season grasses was higher than that of warm season grasses throughout the growing season. The RDP decreased as plant maturity increased for all species. The RUP expressed as a percentage of crude protein for the cool season grasses was lower than that for warm season grasses. The RUP for intermediate wheatgrass, smooth bromegrass, and switchgrass remained constant across maturities, but RUP for big bluestem decreased as maturity increased. Microbial augmentation of RUP decreased as crude protein decreased in all species. The RUP corrected for acid detergent insoluble N and microbial protein was relatively constant across plant maturities. The quantification of RUP across a range of plant maturities provided information for incorporating RUP content of forage grasses into the diets of animals.

Analysis of Variance↗
PubMed1997

Whole cottonseeds or a combination of soybeans and soybeans hulls in the diets of lactating dairy cows.

Whole raw soybeans and soybean hulls were evaluated as a dietary replacement for whole cottonseed as determined by rumination and total chewing activity, milk fat percentage, and efficiency of 4% fat-corrected milk (FCM) production. Twenty-six Holstein dairy cows (14 multiparous; 35 +/- 12 d of lactation) were assigned randomly to one of two total mixed rations (TMR) for 15 wk. The whole cottonseed TMR and the soybean plus soybean hull TMR contained 40% of a 45:55 mixture of alfalfa and corn silages (dry matter basis) and either 15% cottonseed or 15% soybeans, 8% soybean hulls, and 0.7% sodium bicarbonate. Both TMR provided 60% of dietary neutral detergent fiber from forage. The TMR, fed twice daily, were isonitrogenous (17.5% crude protein) and equal in neutral detergent fiber (30%). The TMR had no effect on dry matter intake (24.8 kg/d). The cottonseed TMR stimulated greater rumination and total chewing activity. Although milk production was greater for cows fed the cottonseed TMR (35.7 vs. 34.1 kg/d), milk fat production was unaffected by TMR (3.72%). The efficiency of 4% FCM production was similar for cows fed the cottonseed and soybean plus soybean hull TMR (1.33), and both TMR resulted in a positive net energy balance (10.9 Mcal/d). A combination of soybeans, soybean hulls, and sodium bicarbonate was an effective alternative to whole cottonseed as measured by the efficiency of FCM production.

Animal Feed↗
PubMed1997

Interactions among forages and nonforage fiber sources.

Source, amount, and physical characteristics of dietary forage can interact with nonforage fiber sources and influence ruminal and total tract fiber digestion, passage, and performance of dairy cows fed diets containing substantial nonforage fiber in place of forage. Dietary NDF from forage can be reduced to < = 60% and still provide sufficient amounts of effective fiber for FCM production that is similar to or superior to that with high forage diets. Because of small particle size and high specific gravity, increased ruminal rate of passage may be responsible for lower ruminal NDF digestibility of nonforage fiber sources fed at high dietary amounts. As the amount of soybean hulls increased from 50 to 95% of a pelleted mix for dairy cows, passage rate increased by 8%. In five studies, the digestion of soybean hull diets was improved by the addition of coarse forage. Fiber digestibility might have improved because coarse hay increased ruminal retention time of nonforage fiber sources and allowed more complete digestion. Addition of coarsely chopped alfalfa hay to diets based on silage containing 25% soybean hulls increased ruminal mat consistency by 49% and tended to slow the ruminal escape rate of soybean hulls by 16%. When high percentage of nonforage fiber are fed, the amount of dietary forage is necessarily low, and forage particle size should be adequate to stimulate rumination and entrap small feed particles. The amount and particle size of forage in the diet interacts with the substituted nonforage fiber source to determine the net impact on the rate of ruminal digestion and passage of nonforage fiber.

Animal Feed↗
PubMed1996

Effects of tallow and escape protein on lactational and reproductive performance of dairy cows.

Experiments were performed to determine the effect of energy source and proportion of escape protein on lactational performance, body measurements, and reproductive activity. Sixty-eight lactating Holstein cows were assigned to one of four dietary treatments during wk 2 to 12 postpartum: 1) high fat (3% tallow), high escape protein (5% feather meal:blood meal, 85:15, DM basis); 2) high fat, low escape protein (0% feather meal:blood meal); 3) low fat (0% tallow), high escape protein; and 4) low fat, low escape protein. Diets were similar in energy and CP contents. Overall mean milk yield (32.9 kg/d) was not affected by diet, but efficiency of FCM yield was highest with high fat and high escape protein. Daily DMI and net energy balance were greater for cows fed the diet low in fat and low in escape protein, but days to first ovulation were not different among groups. Total cholesterol in plasma increased as DIM increased, and concentrations were greater for cows fed the high fat diets than for cows fed the low fat diets after 35 DIM. Concentrations of luteal phase progesterone and follicular phase estradiol tended to be greater for cows fed the high fat and low escape protein, but conception rate from first AI was greatest for cows fed the high fat and high escape protein. Supplemental tallow and escape protein did not consistently affect lactational performance but did improve efficiency of FCM yield and conception rate from first AI.

Animal Nutritional Physiological Phenomena↗
PubMed1995

Feeding behavior and management factors during the transition period in dairy cattle.

Little research has focused specifically on the relationships among feeding behavior, management strategy, and optimal intake by the transition cow. Most information must be extrapolated from studies of cattle at other stages of lactation. The transition period can be divided into two distinct phases: 5 to 7 d prepartum, characterized by a 30% reduction in DMI, and 0 to 21 d postpartum, during which time intake should increase rapidly. Feed restriction can reduce number of daily meals by 50%, but when feed is offered for ad libitum consumption, with consistent time of feeding, access can be limited to 8 h daily with no adverse effects on performance of midlactation cows. Sequence of offering feeds may affect intake, but relative degradabilities of dietary protein and starch need to be considered. During early lactation, increased feeding frequency of a total mixed diet may most improve intake when dietary fermentability is moderate to high and management quality is poor. High-producing dairy cows achieve greater intake by increasing meal size and spending less time eating and ruminating per unit of intake. Control of feed intake and meal patterns may differ by parity and should be considered when grouping cattle. Daily exercise of tied dairy cows may not affect intake. Grouping strategy and group feeding behavior influence cow productivity and profitability. Competition for feed and space can be reduced by fenceline feeding vs bunks. Optimum intake during the transition period will occur only if feeding management accommodates normal feeding behavior of dairy cows.

Animals↗
PubMed1995

Brown midrib sorghum silage for midlactation dairy cows.

Brown midrib sorghum silage was compared with alfalfa, corn, and normal sorghum silages for its effect on performance, ruminal metabolism, and digestive kinetics of Holstein dairy cows in midlactation. Twelve cows averaging 90 +/- 5 DIM were assigned to one of four diets in replicated 4 x 4 Latin squares with 4-wk periods. Additionally, 3 ruminally fistulated cows (95 +/- 20 DIM) were assigned to the same diets in a 3 x 4 Youden square for measurement of ruminal characteristics. Diets were fed as isonitrogenous TMR that contained 65% silage (DM basis). The DMI was greater for the corn and brown midrib sorghum (4% of BW/d) than for the alfalfa and normal sorghum diets (3.4% of BW/d). The brown midrib sorghum supported FCM production that was similar to that of cows on corn and alfalfa diets (25.8 kg/d), but cows fed normal sorghum produced less milk and fewer milk components. Source of silage had no effect on eating time, but rumination was least for the alfalfa diet. Ruminal pH and ammonia concentrations were similar for all diets. Total VFA concentrations were greatest for the corn and brown midrib sorghum diets. The brown midrib sorghum had greater in situ extent of ruminal NDF digestion than did the normal sorghum, which agreed with in vitro data. The brown midrib sorghum used in this experiment supported FCM production similar to the corn and alfalfa silages commonly fed to dairy cows in midlactation.

Animal Nutritional Physiological Phenomena↗
PubMed1994

Digestibility of alkali-treated wheat straw measured in vitro or in vivo using Holstein heifers.

Three experiments were conducted to determine the effect of different alkali solutions on in vitro degradation and in vivo digestibility of wheat straw. In Exp. 1, ground wheat straw was treated with 15 different alkali solutions grouped as NaOH, NH4OH, urea, and Ca(OH)2. The greatest (P < .05) 48-h in vitro NDF degradability was obtained with 5% NaOH and the combination of 2.5% NaOH + 2.5% Ca(OH)2. In Exp. 2, chopped wheat straw was treated with one of the following: 1) untreated; 2) 2.5% NaOH; 3) 5% NaOH; 4) 2.5% Ca(OH)2 + 2.5% NaOH; or 5) 5% Ca(OH)2. Five Holstein heifers were fed diets that contained 60% straw, 20% alfalfa hay, and 20% concentrate mix (DM basis) fed as total mixed rations in a 5 x 5 Latin square design. The greatest in vivo NDF digestibility (P < .05) was obtained with the NaOH and NaOH+Ca(OH)2 treatments. The 5% Ca(OH)2 treatment had higher fiber digestibility than the control and was equivalent to the 2.5% NaOH and 2.5% NaOH+Ca(OH)2 treatments. Rate of passage of straw was not affected by chemical treatment, whereas rate of passage of dietary alfalfa hay increased with NaOH. In Exp. 3, wheat straw ground through a 2-mm screen was treated with one of the following chemicals: 1) untreated (control); 2) 5% NaOH; 3) 5% NH4OH; 4) urea supplying N equivalent to 5% NH4OH; and 5) 5% Ca(OH)2 (all on DM basis).(ABSTRACT TRUNCATED AT 250 WORDS)

Alkalies↗
PubMed1994

Soyhulls as a replacement for forage fiber in diets for lactating dairy cows.

Thirty Holstein cows in early and midlactation were fed one of five TMR for 12 wk in which soyhulls replaced 25 or 42% of the forage (alfalfa:corn silages, 1:1, wt/wt, dry basis). Within each amount of soyhull replacement, 33% of the silage was replaced with coarsely chopped alfalfa hay. All diets were isocaloric compared with the control diet, which contained 60% silage and no soyhulls. The high amounts of soyhulls fed with coarsely chopped hay improved DMI, and NDF intake and milk yield by 14, 33, and 9%, respectively, compared with the control diet. Addition of soyhulls at low or high amounts reduced milk fat yield and increased milk protein yield, but addition of hay to the high soyhull diet maintained milk fat yield similar to the control diet. The high soyhull diets increased DM digestibility by 7% compared with the control diet. Rumination time and acetate to propionate ratios were reduced by 43 and 24%, respectively, when high amounts of soyhulls were fed compared with the control diet. Soyhulls can successfully replace 42% of dietary forage when fed in combination with coarsely chopped hay in place of 33% of the dietary silage.

Animal Feed↗
PubMed1994

Altered ruminal mat consistency by high percentages of soybean hulls fed to lactating dairy cows.

Three ruminally fistulated dairy cows in early lactation were used in a 3 x 3 Latin square design with 3-wk periods to investigate the effects of alteration of ruminal mat consistency on ruminal function and soybean hull rate of passage. The control diet consisted of 60% forage (alfalfa:corn silages, 1:1, dry basis) and no soybean hulls. Replacement of 40% of the silage mixture with soybean hulls decreased ruminal mat consistency by 57% at 6 h postfeeding and reduced rumination activity 52%, ruminal pH 6%, and acetate:propionate ratio observed over 24 h by 10% compared with the control diet. Replacement of 75% of the silage with 25% soybean hulls combined with 20% coarsely chopped alfalfa hay increased ruminal mat consistency by 49% at 2 and 6 h postfeeding, increased the percentage of large particles (> or = 9.50 mm) retained in the dorsal rumen, and significantly increased ruminal pH 1.5% and acetate:propionate ratio by 17% compared with the diet of 25% soybean hulls without alfalfa hay. Increasing the ruminal mat consistency with coarsely chopped alfalfa hay did not significantly decrease the rate of escape of soybean hulls from the rumen, but addition of alfalfa hay increased 4% FCM 4.8 kg/d compared with FCM of diets containing 25% soybean hulls without alfalfa hay.

Animal Feed↗
PubMed1994

Comparison of sorghum and corn grains in early and midlactation diets for dairy cows.

Two trials were conducted to compare the effects of corn and sorghum grains on performance of early and midlactation Holstein dairy cows. In trial 1, 36 multiparous midlactation cows were assigned to one of four diets in a 2 x 2 factorial arrangement for 10 wk: 1) grain mixture containing 77% rolled corn fed in a TMR, 2) same grain fed separately from forage, 3) grain mixture containing 77% finely ground sorghum fed in a TMR, and 4) same grain fed separately from forage. Grain source and feeding methods had similar effects on milk yield, milk fat percentage, SNF, SCM, and BW. Cows fed sorghum had higher DMI; cows fed corn had greater efficiency of milk yield. In trial 2, 36 multiparous early lactation cows were assigned to one of four TMR in a 2 x 2 factorial arrangement for 9 wk: 1) TMR containing 35.5% rolled corn, 2) TMR containing 35.5% finely ground corn, 3) TMR containing 35.5% rolled sorghum, and 4) TMR containing 35.5% finely ground sorghum. Grain source produced no differences in DMI, milk yield, milk fat percentage, SCM, and BW. Cows fed finely ground grain yielded more milk than those fed rolled grain. Finely ground sorghum promoted higher milk protein and SNF percentages than did finely ground corn. Total tract starch digestibility was greater for corn than for sorghum. These two trials indicate that sorghum grain, when finely ground, supports milk yield and composition similar to that of corn.

Animal Feed↗