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Effects of breed of service sire and cow on birth weight and prepartum and postpartum endocrine function were studied in multiparous Brahman (n = 20) and Angus (n = 20) cows bred to Brahman or Angus bulls. Before calving, blood samples were collected on d 34 to 28, 27 to 21, 20 to 14, and 13 to 7, and after calving, samples were collected from d 0 to 7. Progesterone (P4), estrogen (E2), and 13,14-dihydro-15-keto-prostaglandin F2α(PGFM) were quantified with RIA. Calves born to Brahman were smaller (P< .05) than calves born to Angus cows. Prepartum concentrations of P4were greater in Angus cows and decreased more rapidly near parturition than in Brahman cows (breed of dam × period; P <.03). Cows bearing bull calves had greater concentrations of P4on d 20 to 14 before calving than cows bearing heifer calves (sex of calf × period; P <.04). Prepartum E2was influenced (P< .05) by the breed of dam × breed of sire × period interaction. The ratio of P4:E2tended to decrease more in Angus than in Brahman cows near parturition (breed of dam × period; P <.09). Postpartum PGFM tended to be influenced (P <.08) by breed of dam × breed of sire; from d 3 to 5, Brahman cows bred to Angus bulls tended (P< .08) to have greater PGFM than Brahman cows bred to Brahman bulls or than Angus cows bred to Brahman or Angus bulls. On d 1 after calving, cows producing heifer calves tended (P <.09) to have greater PGFM concentrations than cows producing bull calves. Hormonal profiles before and after calving were influenced by breed of service sire and cow, sex of calf, and sampling period.

Yearling heifer growth data were obtained during 4 yr for 524 heifers allotted to either humid bermudagrass pastures (Overton) or semiarid rangeland (Uvalde). Each year, heifers were allotted on April 15 to four forage availability levels (400 to 2,800 kg of DM per 100 kg of BW at Uvalde and 80 to 260 kg of DM per 100 kg of BW at Overton) maintained by varying the stocking rate monthly until mid-October of each year. Forage availability and yearling heifer characteristics (weight, condition score, and height at hooks, taken on April 15) were treated as continuous variables in regression analyses. Final heifer weight, height, and condition responses to increased forage allowance were related to yearling phenotypes differently for the two locations. Generally, at Overton, forage availability influenced final characteristics to a greater extent than did yearling variables, whereas the trend was the opposite at Uvalde. At Uvalde, the yearling characteristic that had the largest effect on performance was height at hooks. Yearlings with large frames benefited from increased forage allowance by accumulating body fat at a faster rate than those with small frames. In contrast, at Overton, the yearling characteristic that had the largest effect on performance was condition. Fat heifers responded to increased forage availability to gain even greater advantages in fatness at the expense of potential growth in height and, thus, achieved early maturation. Yearling phenotypes were more broadly adapted to arrays of forage availability for humid, improved pastures than for semiarid rangeland.

Two trials were conducted with mature cows to develop prediction equations for estimating carcass composition from live animal measurements. Trial 1 involved 82 animals that were used to develop these equations. Subjective criteria (frame and condition scores) also were utilized along with live weight in development of prediction equations. Equations using subjective independent variables predicting energy and carcass tissue weights apparently were slightly more variable in precision (R2= .69 to .91) than those developed with objective variables (R2= .74 to .90). Equations predicting percent compositions from subjective variables had lower coefficients of determination (R2= .49 to .76) than those developed with objective variables (R2= .63 to .83). Forty-one animals similar to those used in Trial 1 served as a test group in Trial 2. Measured carcass composition was regressed on composition predicted by equations developed in Trial 1. These equations generally had slopes and intercepts with confidence intervals that included 0 and 1, respectively, indicating that most of the prediction equations were unbiased. This work indicates that carcass composition can be predicted from both objective and subjective measurements, with some accuracy and precision.

Seasonal patterns of forage digestibility and intake were measured over 3 yr for 120, 2-yr-old lactating Angus, Hereford, Angus × Hereford and Hereford × Angus females. These females calved January through March and grazed either fescue-legume (60% fescue, 40% red and ladino clover and lespedeza) or fescue pastures. Forage digestibility and intake were measured with a fecal index developed in a companion study involving 119 in vivo determinations. Dry matter (DM) intake, output and digestibility of forage consumed were calculated weekly from March 1 through September 1. Fecal output was calculated by the Cr2O3-dilution technique. Females grazing fescue-legume consumed 1.3 kg•d−1more forage DM that was 9.7 percentage units more digestible than those grazing fescue. Among-animal range in digestibility varied from 25% (45 to 70% DM digestibility) in April to 37% (47 to 74%) in June for fescue and from 18% (60 to 78%) in May to 31% (45 to 76%) in September for fescue-legume. Breed × pasture type interactions were detected (P<.05) for average and seasonal patterns of both digestibility and intake. The primary interactions involved the crossbreds. Angus × Herefords responded in a similar manner to Hereford × Angus and these were pooled. Crossbreds consumed more (P<.10) DM of lower (P<.10) digestibility than straightbreds when grazing fescue. The opposite trend was detected for females grazing fescue-legume. The opposite nature of the interactions for digestibility and intake effectively countered each other so that breed × pasture type interactions were generally not important (P>.10) for digestible DM intake. Interactions were important (P<.01) when intake was expressed as ratio of metabolic weight. Seasonal pattern of intake and digestibility was also different for crossbreds than for straightbreds grazing either fescue or fescue-legume. Interactions were important for digestibility during seasons of high digestibility and for intake during seasons of low digestibility.

Female weight, fatness, milk production and calf growth were measured to determine seasonal patterns for 120 Angus, Hereford, Angus × Hereford and Hereford × Angus 2-yr-old females grazing fescue or 60% fescue-40% legume. Females calved January through March and calves were weaned in October in each of the 3 yr of the experiment. Preliminary analyses indicated that Angus × Hereford and Hereford × Angus females responded in a similar manner for all variables measured. Angus-Hereford females responded to increased nutrient supply provided by fescue-legume pasture (as compared with fescue) by increasing (P<.05) fatness, especially during late spring, and, to a lesser degree, by increasing (P<.05) milk production and calf growth. Hereford and Angus females, however, responded by increasing (P<.05) milk production (especially during mid-lactation) and calf growth and, to a lesser degree, by increasing (P>.05) fatness. These differential responses resulted in large differences in heterosis for the two pasture types. Calculated heterosis values were relatively large for average female weight and fatness of females grazing fescue-legume, and for weaning weight for those grazing fescue.

Forage intake, milk production, calf growth and efficiencies of milk production and calf growth were estimated for 198 lactations of 91 mature Angus cows grazing fescue-legume or fescue pastures. Cows calved January through March and calves were weaned in October in each of the 5 yr of the experiment. Cows grazing fescue-legume consumed 1.7 kg/d more (P<.01) dry matter (DM) that was 4.6 percentage units more (P<.01) digestible than cows grazing fescue. Cows grazing fescue-legume produced .4 kg/d more (P<.01) milk and weaned 23.8 kg more (P<.01) calf than cows grazing fescue. This increased production required an additional intake/cow-calf unit of 2.3 kg of digestible DM for each additional kilogram of calf weaned. Cows grazing fescue-legume were less efficient in calf production at least partially because they gained 33.3 kg more (P<.01) weight and 1.82 mm more (P<.01) fat cover at the 12th rib during lactation than cows grazing fescue. Cows producing relatively large amounts of milk consumed more digestible DM, weaned heavier calves, and were more efficient producers of milk and weaned calf regardless of pasture type grazed. The influence of milk production on these variables was more dramatic for cows grazing fescue than for those grazing fescue-legume. Cow type favoring maximum conversion of digestible DM intake by cow and calf to calf gain was different for the two types of pasture. For cows grazing fescue, those having either small amounts of fatness or having small structural sizes, regardless of milk production, were the most efficient. Structural size was not related to efficiency for cows grazing fescue-legume. Fatness had little influence on efficiency of low milking cows. The relationship of structural dimension and efficiency for cows grazing fescue was due to interrelationships of structural dimension, change in cow weight and fatness during lactation, and calf weaning weight:cow weight ratio. Relationships between efficiency and fatness could not be attributed to these variables.

Utilization of forage and milk digestible energy (DE) by 153 Angus calves during the preweaning period was measured over a 4-yr period. Estimates of forage intake [internal (Cr2O3), external (H2SO4lignin) marker techniques] and milk intake (weigh-suckle-weigh technique) were made beginning at 109, 142 and 192 d of age for each calf (5-d preliminary and 5-d collection periods). Calves were allowed either fescue-legume or fescue pastures from the time they were born (January through March) until weaned in October. Calves allowed fescue-legume grew more (P<.01) rapidly, consumed more (P<.01) milk and forage and consumed forage of higher (P<.01) energy density than calves grazing fescue pastures. Calves grazing fescue, however, were more (P<.01) efficient in conversion of milk and forage DE to weight gain than calves allowed fescue-legume pastures. Calves allowed fescue depended largely upon milk for growth whereas calves given access to fescue-legume depended more upon forage. As the calves grew, milk intake decreased and forage intake increased. The growth response per increase in milk DE ingested decreased with age whereas the growth response per increase in forage DE ingested increased. When intake was expressed as percentage of body weight, calves consuming forage of low energy density and relatively small amounts of milk did not compensate by increasing forage intake. Calves consuming forage of high energy density, however, compensated for low milk intake with increased forage intake.

Rumen capacities of dry, mature Angus cows (total of 75 cows) were estimated during October of 2 years. Rumen capacity was defined as the rumen lithium sulfate space estimated after consumption to satiety of a cottonseed hull-salt diet under defined conditions. Estimated rumen capacity was studied in relation to: (1) body weight, an estimate of fatness and a series of body measurements taken at the time rumen capacity was estimated, and (2) measures of cow performance during the previous grazing season, including forage intake and digestibility, milk production and weights of calves weaned. During lactation, these cows had grazed either high quality, tall fescue-legume pasture clipped regularly (average dry matter digestibility of 60%) or low quality, tall fescue pasture allowed to mature (average dry matter digestibility of 55%). Digestibility and intake were estimated continuously during the grazing season (152-day period from April 29 to September 28 each year) by the internal (acid detergent lignin)-external (Cr2O3) indicator ratio technique. Type of forage grazed previously was not related to rumen capacity estimates. Structurally large cows (taller at withers; longer, wider at hooks, and deeper at heart girth) had larger (P<.05) rumen capacities than did structurally small cows. As a percentage of body weight, however, rumen capacity was not related (P>.10) to structural size. Fatter, heavier cows had smaller (P<.01) rumen capacities as a percentage of body weight than did thinner, lighter cows. Neither milk production nor calf weaning weight was related to rumen capacity. Among cows that had grazed low quality pasture, a positive relationship (P<.06) existed between rumen capacity and forage intake during the preceeding grazing season. However, no relationship existed (P>.10) between these two factors among cows that had grazed high quality pasture. On the basis of these results, it was hypothesized that forage intake was controlled by different factors for cows grazing high and low quality pastures and that this is probably an underlying cause of genotype × environment interactions.

Postcalving cow weight and subcutaneous fatness change patterns were described for 80 mature spring-calving Angus cows. The cows grazed either high (regularly clipped fescue-legume) or low (fescue clipped once) quality pastures. Forage consumption was estimated continuously by an internal (acid detergent lignin)-external (Cr2O3) indicator technique. Milk production (calf-suckle technique) was estimated seven times during lactation. Wither height was measured during the fall after the period of intensive measurement. Angus cows grazing high quality pasture lost an average of 36 kg postcalving, whereas those grazing low quality pasture lost an average of 22 kilograms. Minimum weights were observed about April 1, prior to the season of large pasture quality differences in digestibility of consumed forage. Taller cows, when allowed increased nutrient density during midlactation (high versuslow quality), responded by increasing (P<.05) fatness at a more rapid rate than less tall cows. For cows grazing high quality pasture, weight change was independent of level of milk production. Cows grazing low quality pasture and giving relatively large amounts of milk maintained less weight and fat during the middle and last part of lactation than did those giving smaller amounts of milk. Shapes of the curves depicting change in weight and fatness were closely related (P<.01) to digestible dry matter intake. Cows apparently consumed forage in such a manner that they became more alike in both weight and fatness as the grazing season progressed.

The diurnal patterns for excretion of chromium sesquioxide (Cr2O3) by 40 mature lactating Angus cows were characterized with the Fourier series: ŷ = AO+ A1sin (ct) + A2cos (ct) + A3sin (2ct) + A4cos (2ct) where ŷ = mg Cr2O3/g fecal DM at time t, AO= mean fecal Cr2O3concentration, c = the fundamental period (radians/hour) and t = time (hours). The period c was circadian and was fixed at .1309 radians/hour corresponding to a 24 hr fundamental period. Cows grazed either high quality (fescue-legume) or low quality (fescue) pastures. Within pasture quality, size of cow was intentionally confounded with pasture (two pastures for each quality). Within-cow standard deviation was .45 mg Cr2O3/g fecal DM. In a general analysis, pasture quality (P<.0001), cow weight (P<.02) and percent butterfat (P<.03) influenced AOmuch more than other Ai(P>.10). Pasture quality interacted with calf weaning weight (P<.02) and percent butterfat (P<.01) in its effect on A1. Calf weaning weight and percent butterfat were associated with variation in A1(P,.05) for cows grazing fescue but not for those grazing fescue-legume pastures. Other Aiin the Fourier series were not affected by variables considered in this study.Each cow's model was estimated at t = 8:00 am and 5:00 pm to evaluate these sampling times for determining average fecal Cr2O3concentration. Regression of AOvalues on the means of data from these evaluations gave a b value of .97 ± .020 (R2= .98).

Efficiency of production of first and second calf Hereford, Hereford × Holstein (Crossbred) and Holstein cows was determined in drylot and estimated for corresponding cattle under range conditions. Within breed, cows were fed either a Moderate or High level of winter supplement. In addition, a group of Holsteins were fed a Very High level. Moderate, High and Very High treatments were the estimated amounts of winter supplement needed in addition to dry winter range grass to sustain an acceptable level of reproduction in Hereford, Crossbred and Holstein cows, respectively. Gross efficiency of production was calculated on the basis of conversion of estimated DE intake to (1) milk, (2) weaned calf, (3) carcass energy and (4) retail cuts.Holstein cows consumed more (P<.005) digestibile energy (DE), produced more (P<.01) milk gross energy (GE) and converted estimated DE to milk GE most efficiently (P<.01), followed by Crossbreds and Herefords, respectively.Although Holstein progeny grew faster (P<.01) to time of weaning and was heavier (P<.01) at weaning, Hereford and Crossbred progeny converted both milk GE and total (creep and milk) DE to weaned weight more efficiently (P<.05). (P<.05).

Purebred Bos indicuscalves are documented to have lower survival rates than Bos tauruscalves. Thus, this study was designed to investigate the possibility that this decreased survival rate may be attributed to dam colostral immunoglobulin (Ig) concentrations and subsequent calf serum Ig concentrations. The specific objective was to determine the effect of breed type of calf on colostrum production, immunoglobulin concentrations in colostrum and calf serum, and availability and absorption efficiency of Ig. Brahman (B) and Angus (A) cattle were reciprocally mated to produce calves of the following types: A × A (n = 8), A × B (n = 9), B × B (n = 11), and B × A (n = 11). At birth, calves were separated from their dams and a blood sample was collected before feeding pooled colostrum (30 mL/kg birth weight) at 1 and 6 h of age. From 6 to 12 h of age, each calf was placed in a box that allowed interaction with the dam but prevented suckling. At 12 h of age, each calf was fed its dam's colostrum and placed with the dam. Additional blood samples were collected at 12, 24, and 48 h after birth. Serum and colostrum samples were analyzed for IgG, IgG1, IgG2, IgM, and IgA using single radial immunodiffusion (RID) assay techniques. The cows were hand-milked after induction of milk letdown with oxytocin at 1 and 12 h after calving. Colostrum volume was recorded, and samples were collected. Brahman cows produced more (P< .001) colostrum at 1 and 12 h than A cows. Total Ig concentrations were obtained by summing IgG, IgG1, IgG2, IgM, and IgA concentrations. Total Ig (P< .02), IgG (P< .005), and IgA (P< .01) concentrations in colostrum were greater in cows producing crossbred calves. Total Ig (P< .006), IgG (P< .02), IgG1(P< .004), and IgG2(P< .02) available in colostrum were affected by B × B and A × B breed types of calf. Brahman cows had more Ig available at 1 and 12 h than A cows due to increased production of colostrum. Breed type influenced colostral Ig in cattle. Serum concentrations of total Ig, IgG, IgG1, IgG2, IgM, and IgA in the calf and efficiency of absorption at 6 and 12 h were not affected by breed type, sex of calf, or any interaction.

Patterns of forage intake, ingesta quality, cow weight and fatness, milk production, calf growth and efficiencies of milk production and calf growth were measured over 5 yr for 197 mature Angus cows. These cows calved January through March and grazed either fescue-legume (70% fescue, 30% red and ladino clover and lespedeza) or fescue pastures. Forage quality and intake were measured by an internal (acid detergent lignin), external (Cr2O3) dilution technique for cows (estimated weekly from April 30 to September 29) and for calves (three, 10-d trials on May 30, June 29 and August 29). Cows and calves were weighed and milk production measured (weigh-suckle-weigh technique) monthly during this time. Cow type at initiation of the study was characterized by a factor analysis that yielded two orthogonal factors identified as frame size and fatness characteristics. These factors were then related to patterns of energy intake, expenditure and efficiency. Large frame cows grazing fescue-legume consumed more (P<.05) digestible energy (DE) during the first part of the grazing season (April 29 through August 29), gave more (P<.05) milk throughout and had faster growing calves than small frame cows. The opposite tendency was noted for cows grazing fescue although the variation among cows was less. Efficiency of conversion of DE (above maintenance costs) to milk was negatively related to frame size for both pasture types but was much more pronounced for cows grazing fescue. Fat cows consumed more (P<.05) DE during the first part of the grazing season than did thin cows regardless of pasture type, but these differences decreased as the season progressed. Among the initially fat cows, those grazing fescue-legume maintained more (P<.05) of their weight and condition during the season than those grazing fescue. Thin cows maintained similar weight and condition regardless of pasture type. Pairs with dams that were initially fat were less (P<.05) efficient in calf growth when grazing fescue-legume but more (P<.05) efficient when grazing fescue.

Angus cow-calf pairs (N=114) were individually fed grass silage diets under conditions chosen to approximate nutrient intake under a free grazing, noncreep situation. Postfactum comparison with a subsequently conducted study on pasture indicated that the procedures used produced animal responses similar to those provided by a tall fescue pasture averaging 58% dry matter digestibility. Cow-calf pair efficiency was expressed as the ratio of estimated total digestible nutrient (ETDN) intake of the pair to calf weight at weaning. Initial cow weight per se was unrelated to pair efficiency. When considered jointly with calf weight at weaning, initial cow weight was unfavorably and calf weight was favorably related to pair efficiency. Calf age at weaning and milk production were favorably related to pair efficiency through their relationship with calf weight at weaning. Initial cow fat thickness, estimated ultrasonically, was not related to this measure of efficiency, indicating compensations between the year just completed and the next year in the relationship between cow fat thickness at weaning and pair efficiency. Mating schemes resulting in selection of relatively smaller females and larger males, within the variation available in a straightbred population, would be expected to alter the cow weight-calf weight ratio in a direction favorable to the component of efficiency defined in this study.

Postweaning growth patterns and preweaning milk and forage intake were observed over a 4-yr period for 137 Angus calves allowed either fescue-legume or fescue pastures preweaning. After weaning, calves grazed fescue pasture until spring for a slow growth phase and then fescue, orchard grass, bluegrass and ladino clover pastures for 4 mo. Following this period, the calves were confined and fed shelled corn and a 36% crude protein supplement until they reached 12 mm of fat over the 12th rib. The spring growing period and the finishing period were classified as a rapid growth phase. Calves that were fatter at weaning lost more fat, but gained more in wither height during the slow growth phase, than those that were thinner at weaning. Apparently, fatter calves were more capable of continuous skeletal growth on a low plane of nutrition because they could retrieve fat energy for this growth. In spring, calves that had been relatively fat at weaning held no advantage in fatness, but had larger frames. Therefore, during the rapid growth phase, they were able to fatten more rapidly than those that were thinner at weaning. Also, calves that were more efficient in preweaning growth had more capacity for rapid postweaning growth when restricted to relatively low quality pasture. Preweaning pasture type influenced pattern of postweaning growth. Part of this influence was associated with differences detected at weaning. An additional part was associated with efficiency of forage and milk utilization during the preweaning phase.

Thirty-nine in vivototal collection digestion determinations were performed with steers with the purpose of relating a selected array of fecal components to forage intake and digestibility. These determinations were made during the spring, summer and fall of 1978 with eight steers averaging 218 kilograms. The forages were freshly cut fescue and frozen green legumes (crimson clover, three cuttings of red clover and lespedeza). Composite fecal samples were analyzed for dry matter (DM), N, ether extract (EE), crude fiber (CF), ash, cell wall constituents (CWC), acid detergent fiber (ADF), acid detergent lignin (ADL), acid insoluble ash (AIA), urobilinogen (UROB), in vitroDM digestiblity (IVDMD), Na and Zn. Hemicellulose, cellulose, acid soluble ash (ASA) and N-free extract (NFE) were calculated. Fecal components related (P<.10) to DM intake (DMI) were: DM, N, CF, EE, NFE, ASA, IVDMD and Zn. Those related (P<.10) to DM digestibility (DMD) were: DM, N, CF, ash, NFE, ASA, IVDMD, CWC and Zn. The best multiple regression equations (highest R2, with all independent variables significant) for estimating DMI, fecal DM output (FDMO), DMD and digestible DMI (DDMI) had R2values of .69, .35, .65 and .74, respectively. The respective residual standard deviations (RSD) for these models were: .46 kg/day, .20 kg/day, 7.07% and .41 kg/day. The equation for estimating DDMI was: DDMI = −6.66 + 1.65(N) + .37 (EE) + .08(CWC) − .08(DM). The equation, DDMI = −1.13 + 1.32(N), had an R2of .44 and a RSD of .58 kg/day. The addition of between-animal variation to these models improved (P<.01) R2only for DMI and DDMI, accounting for about 11% of the variation in each variable. Most of this between-animal variation was due to variation in weight. Fecal N indices do not have broad application, because the relationship between fecal N and forage intake or digestibility changes as season of year, N in forage and species consumed change, but the addition of EE, CWC and DM to models containing N largely overcomes these problems. Therefore, the development of useful fecal indices with fairly broad application appears possible.

Forage digestibility, intake and animal performance (cow and calf weight and fatness change, cow milk production and milk composition) were measured for 79 lactations of Angus cows during a 2-year period. Cows grazed either tall fescue-legume pastures clipped at regular intervals (high quality) or tall fescue pastures allowed to mature (low quality). Digestibility and intake were estimated by the internal (acid detergent lignin)-external (Cr203) indicator ratio technique continuously from April 29 to September 28 (152 days) each year. Cows grazing high quality pastures consumed 1.7 kg/day more DM (10.5 vs8.8 kg/day, P<.01) and 1.3 kg/day more digestible DM (6.4 vs5.1 kg/day, P<.01) than cows grazing low quality pastures. Forage consumed from high quality pastures was 2.5 percentage units higher in DM digestibility (60.8 vs58.3%, P<.01) than was forage consumed from low quality pastures. Pasture quality differences were the result of large advantages for the high quality pastures during the summer. Cows on both pasture qualities, however, produced similar (P>.82) amounts of milk although milk from those on high quality pastures contained .42 percentage units more (P<.04) butterfat. During the experimental period cows on high quality pastures gained 18 kg more (P<.01) weight and 2.8 mm more (P<.01) subcutaneous fat than those on low quality pastures. They also weaned calves that were 18 kg heavier (P<.01) at adjusted 240-day calf age.

The effects of breed of dam and level of winter supplement on subsequent postweaning feedlot performance of 213 steer and heifer calves from Hereford, Hereford × Holstein (Crossbred) and Holstein cows were determined. Calves fed in 2 succeeding years were sired by Angus (trials 1 and 2) and Charolais (trials 3 and 4) bulls. Each year calves that had been reared on range preweaning were group-fed (trials 1 and 3) and calves that had been reared in drylot preweaning were individually fed (trials 2 and 4).Very few of a large number of variables were influenced by level of supplement received by the dam. In breed of dam comparisons, Holstein progeny (calves from Holstein cows) was heavier initially (62 kg) and at slaughter (113 kg) than Hereford progeny (calves from Hereford cows). Crossbred progeny (calves from Crossbred cows) was intermediate for these traits. Holstein progeny was taller (9.5 cm) and longer (7.1 cm) initially, taller (10.4 cm) and longer (9.8 cm) at slaughter, required a longer feeding period (49 days) and was older at slaughter (49 days) than Hereford progeny; Crossbred progeny was intermediate in these traits but tended to respond more like Hereford than Holstein progency.Hereford and Crossbred progeny gained faster (.13 and .08 kg daily) than Holstein progeny. Crossbred and Holstein progeny consumed more daily feed (4 and 11%) and more total feed (14 and 43%), and required more feed per unit of gain (9 and 27%) than Hereford progeny.