D.W. Kellogg

Effects of Zinc Methionine Complex on Milk Production and Somatic Cell Count of Dairy Cows: Twelve-Trial Summary

The objective of this review was to summarize 12 trials (13 comparisons) evaluating effects of zinc methionine (ZM) complex (ZINPRO®; Zinpro Corporation, Eden Prairie, MN) on lactation performance and udder health. Summarized trials were conducted in Washington (2), Colorado (2), New York, Illinois, Arkansas, Missouri, Georgia, Great Britain, Germany, and Israel. In 5 of the trials, ZM provided between 180 and 200 mg of zinc/d per head; in the remaining 7 trials (8 comparisons), ZM supplied 360 to 400 mg of zinc. In all diets, cows received additional zinc from inorganic sources, with the exception of the control diet in one of the Missouri comparisons. For statistical evaluation, each trial was considered as a block, and the treatment least squares mean within a trial was treated as an observation using a mixed model. Cows fed ZM produced more (P 0.15) between treatment and control cows. Somatic cell count (SCC; 1000/mL) was reduced from 294 to 196 (P<0.01) in cows receiving ZM. This summary of 12 dairy trials indicates that ZM increases lactation performance and improves udder health, as a 33.3% reduction in SCC occurred.

Sire Breed Effects on Preweaning Traits of Crossbred and Purebred Calves from Angus or Hereford Dams

Abstract The objective of this research was to evaluate variation in calf performance from birth to weaning attributable to breed of sire (BRS), breed of dam (BRD), sex of calf, and all interactions. Records from 2,352 calves born at the Pinetree Research Unit of the Arkansas Experiment Station were utilized in the study. Physical environment and the available production resources make this location one of the more challenging environments for feeder calf production in the state. Some of these challenges include, but are not limited to, abundant rainfall, poorly drained soils, limited number of improved forage species, endo- and ectoparasites, fescue toxicities, and anaplasmosis. Calves resulted from mating Angus and Hereford dams to Angus, Hereford, Charolais, Santa Gertrudis, or Red Poll sires. Calf data collected were birth date, birth BW, preweaning ADG, weaning BW, weaning grade, and weaning body condition score (WBCS). Year, age of calf, BRD and BRS were significant (P

Case Study: Performance and Ensiling Characteristics of Tall-Growing Soybean Lines Used for Silage1

ABSTRACT Seven tall-growing soybean (Glycine max [L.] Merr.) lines, including the cultivars Derry, Donegal, and Tyrone plus the experimental lines OR 5-12-1T, OR 13-12-3, OR 19-12-2, and PA 5-2-1, were harvested, ensiled, and tested for nutritive quality to evaluate the potential of these lines as silage crops. Tall-growing (or forage) soybeans were compared with a grain-type Group V soybean (Hutcheson) and forage sorghum (Sorghum bicolor [L.] Moench) (Pioneer 838 F). Lines were replicated four times at sites near Fayetteville and Rohwer, Arkansas in 1995 and 1996, harvested at full seed (soybean growth stage R-6), and ensiled for 33 d. Derry, Donegal, and Tyrone produced average DM yields for both years of 5,216, 7,118, and 6,900 kg/ha at Fayetteville and 6,738, 6,398, and 6,300 kg/ha at Rohwer, respectively. The tallest entries grown in Fayetteville were Tyrone and OR 13-12-3; Derry was tallest at Rohwer. Average concentrations of NDF, ADF, CP, and IVDMD in silage from Derry, Donegal, and Tyrone were 41.8, 43.9, and 43.1%; 33.0, 33.6, and 33.2%; 12.6, 14.2, and 14.0%; and 70.4, 72.1, and 70.6%, respectively, at Fayetteville and 47.4, 49.0, and 43.1%; 33.9, 37.0, and 31.3%; 13.8, 16.0, and 13.7%; and 63.0, 66.8, and 62.5%, respectively, at Rohwer when averaged over both years. Silage for all lines was well preserved as indicated by the low final pH and a high lactic acid concentration. Of the forage soybean lines tested, PA-5-2-1 and Donegal had consistently higher nutritive values at both locations for 2 consecutive yr.

Use of a Dry Bottle to Feed Starter Grain To Holstein Calves

Twenty Holstein calves from 1 to 35 d of age were offered grain in either an open plastic bucket (control) or in an enclosed plastic bottle. After the 35-d trial, control calves were fed 1.8 L of whole milk twice daily for 7 d, then reduced to once daily and weaned at 56 d of age, whereas milk for calves receiving grain in bottles were given one daily feeding of 1.8 L of milk and were weaned at 42 d of age. Body weights were taken weekly, and feed intake was calculated daily. Blood serum was collected at weekly intervals from four calves for measurement of β-hydroxybutyrate. During wk 1 calves fed grain with the dry bottles consumed more (P .10) between treatments throughout the trial. Feed consumed per unit of body weight gained did not differ (P > .10). β-hydroxybutyrate concentrations were similar (P > .10) during the trial. Young calves used the specially designed nipples during the first week of life and initiated grain intake earlier. The dry bottles protected grain from rain and flies compared to placing grain in an exposed bucket.

Preference of Dairy Cows for Free-Stalls Bedded with Sand or Granite Fines and Changes in Bacterial Counts in Those Materials

Abstract Sand and granite fines were compared as bedding in free stalls for lactating cows. Eighteen stalls were randomly bedded with sand or granite fines. Lactating cows [100 to 160; 31 to 90 d in milk (DIM)] had access to these stalls plus 142 other stalls bedded with sand. Experimental stalls were observed on 6 d (4 times/d) during the 27-d study. Using a logistic procedure, experimental stalls bedded with sand were 2.8 times more likely to be used than those bedded with granite fines (P

Change in hoof phosphorus content for bulls in a 112-day postweaning feedlot performance test

Abstract Hoof samples for mineral analysis from four breed groups of bulls—Angus (n=20), Brangus (n=19), Hereford (n=31) and Simmental (n=53)—obtained during a 112-d postweaning feedlot performance test were used to study effects on the change in hoof phosphorus (P) concentrations. Hoof samples were obtained for mineral analysis from the right front foot of all bulls on d 1 and 112 of four tests conducted in three locations in Arkansas. Data were analyzed using least-squares analysis of variance. The model included terms for common element, an effect due to test, breed, farm of origin within breed, hoof pigment, initial age and residual error. Breed means were separated using repeated t-test. Residual correlations between P and other hoof minerals were obtained. Breed was the only significant source of variation on the change in hoof P. The model explained 45% of the variation (R 2 ). Breed means for the change in P showed both Angus and Brangus bulls significantly different ( P P P

Growth, Luteal Activity, and Pregnancy Rates of Three Breed Types of Dairy Heifers in a Forage-Based Development Program

Growth, luteal activity, and pregnancy rates were evaluated in 89 dairy heifers raised as contemporaries. Breed types were Holstein (H, n = 35), Jersey x H (JH, n = 30), and Brown Swiss x H (BSH, n = 24); they ranged in age from 129 to 205 d at the beginning of the trial. Heifers grazed pasture and received grain supplementation to ensure 0.9 kg of daily BW gain. Hip height, chest depth, and BW were obtained monthly; BCS was recorded at ca. 14 mo of age. At ca. 12 mo of age, two blood samples for each heifer were collected (10 d apart) by jugular vein puncture for progesterone assay. Heifers were considered cycling if progesterone concentrations were > 1 ng/ mL in either of the two serum samples. Heifers were bred artificially (AI) on a synchronized estrus starting at 14 mo of age, and pregnancy status was determined ultrasonically 60 d after breeding. The BSH and H had similar (P>0.05) weights and hip heights; whereas JH were lighter and shorter (P 0.05) occurred for depth of chest and mean BCS. Estrus occurrence by 12 mo of age was greater (P<0.05) for JH (90%) than for BSH (75%) and lowest (P<0.05) for H (47%). Pregnancy rates did not differ (BSH = 96%, JH = 87%, H = 77%). These data suggest that genetic effects of crossbreeding influence early growth and cyclicity at 12 mo of age for replacement dairy heifers. Forage-based development of dairy heifers may be a suitable option to concentrate feeding for dairy producers in Arkansas and the Southern Region.

Effect of Replacing Dried Skim Milk with Peptone Concentrate, Whey, and Dextrose in Milk Replacer on Weight Gain and Feed Efficiency of Holstein Calves1

Peptone concentrate (PC; 50% DM), an enzymatically hydrolyzed protein derived from swine intestines, was spray-dried with 17% whey and 3% emulsifier (PC-W) to prepare a satisfactory, water-soluble component of milk replacer with no unusual odor. Four milk replacers were prepared with 0, 2, 4, or 8% PC-W and 0, 1, 2, or 4% dextrose replacing 0, 3, 6, or 12% dried skim milk. Forty male Holstein calves (1 to 4 d old) were placed in hutches for 6 wk. Starter grain was offered in plastic, dry bottles fitted with a specialized nipple to all calves from d 10 to 42. Weight gain was similar for calves fed 0, 2, and 4% PC-W (18.9, 19.4, and 21.0 kg, respectively) but was lower (P<.05) for calves fed 8% PC-W (13.6 kg) than for other milk replacers. Most of the negative effect on weight gain With 8% PC-W occurred during the first 3 Wk of age, perhaps because dietary content of sodium, chlorine, and sulfur increased due to the contribution of 6.4% PC (9.2% sodium chloride and 10.6% sodium bisulfite, DM basis). Based on these results, 4% PC-W and 2% dextrose can replace 6% dried skim milk in milk replacers formulated for young dairy calves.

Relationships of Hoof Characteristics and Selected Hoof Minerals of Bulls in a 112-Day Postweaning Feedlot Performance Test1

Observations on hoof growth of Angus (n = 20), Brangus (n = 19), Hereford (n = 31), and Simmental (n = 53) during a 112-d postweaning feedlot performance test were used to study hoof characteristics relative to hoof mineral composition. Hoof measurements, scores, and .5-g hoof samples were obtained from the right front foot of all bulls on d 1 and 112 of four tests conducted in three locations in Arkansas. Data were analyzed using least squares analysis of variance. The model used included terms for an overall mean, test, breed, farm of origin within breed, initial age, and initial weight within breed and residual error. Means were separated using repeated t-test. Residual correlation coefficients were obtained from the residual sum of squares. Test and breed were significant for hoof angle but not for hoof growth, hoof score, and hoof pigment. Farm of origin within breed, initial age, and initial weight within breed were not significant for any hoof trait. The model explained .72, .39, .42, and .83 of the variation (R2) of the main effects of hoof angle, hoof growth, hoof score, and hoof pigment, respectively. Hoof angle for Angus and Brangus bulls was different (P<.05) than hoof angle of Hereford and Simmental bulls. Significant residual phenotypic correlations were found for hoof angle, hoof growth, and hoof score with some hoof minerals. These data indicate that there are breed effects on hoof angle and that a relationship exists among the mineral content of hooves and both hoof measurements and scores.

The Influences of Bovine Leukemia on Milk Quality and Yield within a Purebred Holstein Dairy Herd

Abstract Dairy Herd Improvement (OHI) and herd health records from 1981 through 1989 were used to assess the impact of bovine leukemia virus (BLV) in a purebred Holstein herd with emphasis placed upon milk yield, percent fat, percent protein, and somatic cell counts (SCC). Completed lactations were stratified from 1 to 5 for comparison of variables. Only data of cows milking at least 210 d were analyzed, and data from all cows that seroconverted during the 8-yr period were not included. Seropositive (BL V +) cows produced more (P>0.05) milk during lactations 3 and 5 than seronegative (BLV-) cows with no significant differences in percent fat. Percent protein was significantly higher in 1 st lactation BLV- cows followed by increased SCC in milk during the 2nd lactation compared to BL V + cows. More research is needed to elucidate the manner by which BLV infection affected milk composition. Obviously the analyses conducted on milk yield, percent fat, percent protein, and SCC were the result of unique selection pressures that concentrated the higher producing BLV+ cows after the 2nd lactation. Superior BLV- cows were removed and sold for breeding stock, and those remaining were utilized to propagate more BLV-free offspring. Therefore, milk yield was indirectly influenced by the presence of BLV within this purebred dairy herd.