Effects of hydrolyzed spray dried red blood cells in milk replacer on calf intake, body weight gain, and efficiency.

An alternative protein ingredient based on spray-dried, hydrolyzed red blood cells was evaluated in calf milk replacers. Two experiments were conducted to determine the value of the ingredient on intake, growth, and feed efficiency in dairy calves. In experiment 1, Holstein bull calves (n = 120) were fed calf milk replacer containing 0, 11, 22, or 43% of crude protein as spray dried hydrolyzed red blood cells. Calves were fed 454 g/d of experimental milk replacer reconstituted to 12% dry matter plus a conventional calf starter for 28 d. Body weight gain, intake of milk replacer and calf starter, feed efficiency, fecal scores, and days scouring were unaffected by source of protein. In experiment 2, Holstein calves (n = 69) at the University of Minnesota, Crookston and Waseca were fed milk replacer containing 0, 22, or 43% of crude protein as spray dried hydrolyzed red blood cells. Calves were fed 454 g/d of experimental milk replacer reconstituted to 12% dry matter plus a conventional calf starter containing 0 or 25% alfalfa meal for 35 d. No calves died during the study. Body weight gain, feed efficiency, intake of calf starter and milk replacer, fecal scores, and days scouring were unaffected by increasing hydrolyzed red blood cells in milk replacer. Similar performance of all calves indicated that spray dried hydrolyzed red blood cells can replace up to 43% of crude protein from whey protein concentrate without detrimental effects on animal performance.

Productive life and reasons for disposal of Holstein cows selected for large versus small body size.

Holstein cows were compared for direct and correlated responses to selection for large versus small body size. The divergent selection lines differed for body weight, body dimensions, and birth weight of calves but did not differ for production or calving ease. Also, cows in the small line required fewer services to conception during first lactation than did cows in the large line. Cows in the body size lines differed for three reasons for disposal: udder conformation, which favored cows in the large line; problems with legs and feet, which favored cows in the small line; and a miscellaneous category, which included internal infections and favored cows in the small line. Productive life to a maximum of 6 yr was 87.7 d (15.4%) longer for cows in the small line than for cows in the large line. Continued selection for larger Holstein cows in North America might not be economically justifiable.

Yield response of lactating Holstein dairy cows to dietary fish meal and bone meal.

Experiments were conducted to examine the effects of the source and amount of dietary protein on yield and composition of milk from Holstein dairy cows. Study 1 used 36 multiparous cows at 125 +/- 59 d in milk in, a replicated 2 x 2 Latin square design. Treatments were diets formulated to contain 16% crude protein (CP) in which 11% was fish meal or meat and bone meal supplied 11% of dietary CP. Intakes of dry matter, CP, and net energy for lactation; yields of milk; and percentage of milk fat were not affected by treatment. Fish meal increased contents of milk total N, casein N, and noncasein N but did not increase contents of NPN; fish meal also tended to increase milk CP yields. Study 2 used 78 cows (31 primiparous) at 31 +/- 2 d in milk in a randomized block design. Two treatment diets were formulated to contain 16 or 18.5% CP, and soybean meal was the sole source of supplemental protein in those diets. The two other treatment diets were, formulated to contain 16% CP; in these diets, fish meal or meat and bone meal partially replaced soybean meal. Treatments did not influence yield or composition of milk from multiparous cows. Compared with a soybean meal diet containing 16% CP, a soybean meal diet containing 18.5% CP or diets containing 16% CP and containing meat and bone meal or fish meal increased the milk, yield of primiparous cows similarly. Fish meal or meat and bone meal increased the efficiency of protein utilization for milk yield.

The effect of dietary energy concentration on calf performance.

At three locations, 120 calves were fed a high fat milk replacer at 10% of birth weight from d 5 through 13. On d 14, calves were assigned randomly within sex and date of birth to a 2 x 2 factorial arrangement of treatments. Treatments were (on a DM basis) high fat milk replacer (21.6%) and high fat starter (7.3%), high fat milk replacer (21.6%) and low fat starter (3.7%), low fat milk replacer (15.6%) and high fat starter (7.3%), and low fat milk replacer (15.6%) and low fat starter (3.7%). Milk replacer was fed at 8% of birth weight/d from d 14 to 35 and at 4% of birth weight/d from d 36 to 42. High fat replacer depressed DMI before and after weaning. High fat starter depressed DMI after weaning. Before weaning, calves gained more BW when fed low fat replacer. Calves fed low fat starter gained more BW after weaning. On d 56, BW were highest for calves fed low fat replacer and starter and lowest for those fed high fat replacer and starter. Growth or health of calves was not improved by fat addition to the diet.

Calving disorders of primiparous Holsteins from designed selection studies.

Primiparous Holsteins from designed studies were evaluated for edema, dystocia, and retained placenta. Genetic studies were 1) selection for large body size versus small body size, and 2) milk yield selection versus control (no selection). The large body size group was mated to sires with extreme estimates of transmitting ability for tall height and deep and wide bodies. Small body size group was mated to extreme sires for transmitting short height and shallow, narrow bodies. Large and small cows significantly differed only for edema, and small cows had scores suggesting more severe udder edema than large cows. Milk selection group was mated to the four highest sires for PTA milk each year, whereas a control group was mated to 20 randomly selected AI sires that were breed average for PTA milk in 1964. Selection groups for milk yield did not differ significantly for any of the calving disorders.

Evaluation of white lupines and triticale in calf starter diets.

One hundred fifty-two Holstein calves were used to evaluate white lupines (Lupinus albus cv. Ultra) and triticale in starter diets. The basal diet contained corn, oats, minerals, and vitamins. Starter components were 1) 14% soybean meal; 2) 10% soybean meal and 27% triticale; 3) 22% lupines; 4) 16% lupines and 24.5% triticale; 5) 11% lupines and 8% soybean meal; and 6) 7% lupines, 5% soybean meal, and 26.5% triticale. Dietary CP was approximately 16% of DM. Data collection began on d 4 after birth and continued through d 56. Calves were fed 3.6 kg of fermented colostrum from d 4 to 14 and 4.5 kg of fermented whole milk from d 15 to weaning at d 28. Starter diets and water were offered for ad libitum consumption from d 4 to 56. Dietary treatment had no effect on starter intake or weight gains. Average total gains during the experimental period were 25.6, 23.0, 23.3, 23.2, 25.0, and 21.6 kg for treatments 1, 2, 3, 4, 5, and 6, respectively. Calf health was excellent. Starter diets were examined in a dual flow continuous culture system to evaluate fermentation by rumen bacteria. Digestibilities of DM, organic matter, and total nonstructural carbohydrate did not differ among treatments. Ammonia N concentrations ranged from 11.9 to 13.8 mg/100 ml effluent. Chemical composition of bacteria, efficiency of bacterial protein synthesis, total VFA concentration in the effluent, and amino acid flow were similar for all treatments. The results indicate that lupines and triticale are satisfactory for use in calf starters when included in amounts equal to or less than those used in this experiment.

Effects of selection for body size on feed efficiency and size of Holsteins.

First lactation records from a herd of Holstein cows bred for either high production and large size or for high production and small size were examined to estimate effects of selection for size and feed efficiency. Selection was among progeny-tested bulls available from the artificial insemination industry. Three rations were fed that differed for ratios of concentrate to milk. After three generations, groups of cows bred for large or small size differed by 50.2 kg in weight, 5.6 cm in wither height, 6.4 cm in length, 2.1 cm in depth, and 5.9 cm in chest circumference; most differences were due to a decrease in the size of the small cows. On the basis of total lactations, cows bred for small size were 2.8% more feed efficient than cows bred for large size. During the first 90 d of lactation cows fed the low concentrate ration were more efficient than those fed the high concentrate ration. Season of calving had an effect on feed efficiency between d 30 and 120 of lactation. During this period cows calving between December and May were more efficient.

Effect of compensatory growth on regulation of growth and lactation: response of dairy heifers to a stair-step growth pattern.

The primary objective of this study was to improve the productive efficiency of growth via optimal use of both high fiber-low quality and high energy-high protein feeds in diets for growing dairy cattle. Twenty Holstein heifers were randomly assigned to either a control or treatment group. The control diet met the National Research Council (NRC) requirement for .45 kg/d gain, with heifers calving at 24 to 26 mo of age. The test groups were fed according to a 5-2-5-2 mo schedule in which the nutrient density was alternately 15% below or 40% above the NRC requirement. Results showed that the heifers on the test dietary regimen (compensatory growth) gained more and consumed less, resulting in significantly improved efficiency of growth (body gain/dry matter intake X 100), energy (body gain X 1,000/metabolizable energy (ME) intake) and protein utilization (body gain/protein intake X 100) in comparison to control animals (13.0 vs 7.3%; 57.9 vs 32.6 g/Mcal ME; 96.5 vs 54.2%, respectively). Marked changes in average concentration of urea-N, glucose, triglycerides, cholesterol and lecithin cholesterol acyltransferase activity in blood were seen for test heifers during the stair-step growth phase (i.e., alternating maintenance and compensatory). Evidence from this experiment suggests that the phased growth (stair-step) system offers a simple, practical and cost-effective method for raising dairy heifers.

Health care of Holsteins selected for large or small body size.

Genetic groups of Holsteins selected for large size or small size were compared for health care needs. Two groups were formed from a paired foundation population. Large group was mated to sires with extreme estimates of transmitting ability for tall height and deep and wide bodies. Small group was similarly mated to extreme sires but to those transmitting short height and shallow and narrow bodies. Predicted Differences for milk and fat of sires were above breed average. Actual expenses for veterinary treatment, health supplies and drugs, and value of labor required of animal attendants were evaluated. Large cows required significantly more health care than small cows. Digestive disorders accounted for much of the group difference, and displaced abomasums were more frequent among large cows. Small cows may have economic advantages over large cows of the same breed.

Dietary sodium bicarbonate for high-producing Holstein cows over complete lactations.

Several concentrates with sodium bicarbonate (experimental) were compared with the same concentrates without sodium bicarbonate (control) throughout two lactations. During first lactation, two control concentrates were used in sequence in one comparison and three in another. Toward the end of first lactation, sodium bicarbonate was increased from 1.5 to 2.5% in concentrates, and that concentration was continued throughout the second lactation. During second lactation high-moisture corn with soybean meal was one concentrate; the other included half high-moisture barley and half dry corn and soybean meal. Fifty-two and 60 lactations of cows fed control and experimental rations contributed feed intake and production data. Ninety-four and 95 lactations of cows fed control or experimental rations contributed 305-day, mature-equivalent production data over three lactations. Inclusion of sodium bicarbonate in these rations had little effect on feed consumption, milk production, fat content of milk, efficiency of milk production, or change of body weight. The kind of concentrate did not alter the effect of sodium bicarbonate. Cows consuming control rations produced 8898 kg milk with 312 kg fat (305-day mature equivalent). Cows using bicarbonate produced 8972 kg milk with 312 kg fat.

Feed intake and milk production from three rates of concentrate for cows bred to differ in size.

Two groups of Holstein cows sired by bulls that had been selected partly for transmitting ability for size averaged 525 and 570 kg weight after second calving. Cows were fed 1.0 kg concentrate to 5.0, 3.0, or 1.5 kg milk above 9.1 kg per day and forage to appetite during first and second lactations (248 lactations). Generally equal quantities of alfalfa haylage and corn silage were fed each day in weighed amounts to exceed consumption. At times haylage constituted the only forage fed. Results of feeding low (2.2 kg), medium (3.8 kg), or high (6.9 kg) concentrate dry matter daily per cow were: concentrate as a percent of total dry matter consumed, 12.2, 20.2, and 37.1%; dry matter intake from forage, 15.6, 14.5, and 11.6 kg/day; dry matter intake as percent of body weight, 3.25, 3.32, and 3.33; crude fiber as percent of dry matter consumed, 25.2, 23.6, and 20.5; crude protein as percent of dry matter consumed, 15.7, 15.4, and 15.1; total digestible nutrients consumed per day, 10.8, 11.4, and 12.2 kg; milk produced as milk/day, 18.7, 19.9, and 21.3 kg; fat-corrected milk/day, 18.6, 20.0, and 20.7 kg; fat-corrected milk as percent of body weight, 3.44, 3.68, and 3.78; and fat-corrected milk as gram per weight kg .75, 166, 178, and 183; fat content of milk, 4.00, 4.11, and 3.92%; protein content of milk, 3.49, 3.58, and 3.61%; gross efficiency of milk production, .591, .579, and .595 kg total digestible nutrients/kg fat-corrected milk; and net efficiency, .304, .308, and .332 kg total digestible nutrients/kg fat-corrected milk. Cow size, parity, and period of lactation affected most variables. These latter effects are illustrated in graphs or tables.

Effect of dietary fat supplement on lipid metabolism of Holstein Heifers.

Twenty Holstein heifers were fed four rations containing 0, 10, 20, and 30% whole sunflower seed as a source of dietary fat. All rations consisted of alfalfa hay, sunflower hulls, and grain mixtures and were isonitrogenous at 12% crude protein and isocaloric at 2.6 Mcal metabolizable energy per kilogram dry matter. Average body weight gains were not different among treatment groups. Heifers fed sunflower seed (fat) diets consumed less total dry matter, significantly improving growth efficiency (gain/feed). Concentration of total lipid and urea nitrogen in blood serum were increased whereas glucose was depressed with higher amounts of dietary fat. High fat diets (20 and 30%) elevated total lipid, triglyceride, and nonesterified fatty acids in the blood. Total and free cholesterol in blood also were increased, but high density lipoprotein-cholesterol remained unchanged with increasing concentration of dietary fat. Dietary fat was correlated positively with lipid components of blood serum and negatively with glucose.