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An experiment was conducted to measure production responses of an alternative cow-calf production system integrated into a cropping system without access to perennial forage compared to a traditional cow-calf system utilizing perennial forage. Multiparous, cross-bred beef cows (n = 160; average age = 6.2 ± 2.8 yr) were utilized in a randomized complete block experimental design and unstructured treatment design. Upon initiation, cows were blocked by age and stratified by source, assigned randomly to one of two production systems, each with four replicates (n = 20 cows/replicate). Once allotted to their treatment groups, cows remained in their experimental units for the duration of the experiment. Treatments were: 1) a traditional system consisting of April to May calving with smooth bromegrass pasture and grazed corn residue as forage resources (TRAD); 2) an alternative system consisting of July to August calving utilizing partial-drylot feeding, summer-planted oats, and corn residue grazing (ALT). There were no differences (P ≥ 0.27) in calving rates (91.8 vs. 86.7 ± 2.92%), pregnancy rates (89.3 vs. 89.9 ± 2.66%), and weaning rates (87.2 vs. 82.3 ± 3.29%) for TRAD vs. ALT, respectively. However, there was an increase (P = 0.04) in the rate of twin offspring in ALT (2.9 vs. 9.4 ± 2.36% for TRAD vs. ALT, respectively). One calf from the set of twins was selected randomly at birth to be removed from the experiment, so the production data are only from single calves. There was no difference (P = 0.47) in calf body weight at birth (40 vs. 39 ± 0.7 kg for TRAD vs. ALT, respectively). At weaning, calves in the ALT system were lighter (P < 0.01) at the same day of age (184 vs. 229 ± 5.5 kg) compared to TRAD calves. Cows from the ALT system had fewer (P < 0.01) kg weaned per cow exposed to bull (150 vs. 199 ± 7.2 kg) compared to TRAD cows. Apart from the twinning rate, no differences in reproductive performance were observed among systems. However, reduced weaning weights and kilogram of weaned calf per cow exposed may negatively impact revenue to the cow-calf enterprise of the ALT system. [ABSTRACT FROM AUTHOR]

To determine the effects of harvest method and ammoniation (3.7% of dry matter) on consumption and waste of baled corn residue, a 6 × 6 Latin square with a 3 × 2 factorial treatment structure was conducted. Six treatments consisted of either nonammoniated or ammoniated residue, harvested one of three ways: conventional rake and bale (CONV), New Holland Cornrower with two rows of stem chopped into the windrow with tailings (2ROW), or EZBale system (EZB) with a disengaged combine spreader and tailings dropped in a windrow. Open cows were grouped by body weight to produce a light block of two pens (448 kg ± 49.6) and a heavy block of four pens (649 kg ± 65.9). One bale was fed to each pen during each of six 7-d periods using round bale ring feeders with closed bottom panels. Residue falling around (waste) and remaining in (refusals) the feeder was collected. The daily nutrient intake was estimated as the difference between what was offered and what remained (waste plus refusals). Crude protein (CP) of residue offered did not differ (P = 0.58) among harvest methods. The digestible organic matter (DOM) content of residue offered in 2ROW and EZB bales did not differ (P = 0.86) and was greater (P < 0.01) than CONV. Ammoniation increased (P < 0.01) CP and DOM content of the residue offered. Total wasted and refused residue did not differ (P = 0.12) between 2ROW (29%) and EZB (37%), while CONV (42%) was greater (P = 0.02) than 2ROW but did not differ (P = 0.34) from EZB. Ammoniation reduced (P = 0.03) total waste and refusals from 41% to 32%. The nutrient content of both waste and refusals did not differ (P ≥ 0.34) among harvest methods and, with the exception of CP, was not affected (P ≥ 0.15) by ammoniation. The CP content of the waste was greater (P = 0.02) and refusals tended to be greater (P = 0.08) from ammoniated bales. The CP intake of 2ROW was greater (P ≤ 0.02) than both EZB and CONV, while EZB tended (P = 0.06) to be greater than CONV. The CP intake of all ammoniated residues was greater (P < 0.01) than the nonammoniated residue. The DOM intake of nonammoniated 2ROW and EZB did not differ (P = 0.61) but was greater than nonammoniated CONV (P < 0.01). Ammoniation increased (P < 0.01) DOM intake. Overall, ammoniation had much larger effects than harvest method, resulting in reduced waste and refusals and greater intake of DOM and CP. However, the combination of both ammoniation and selective harvest (2ROW or EZB) was needed to result in energy and protein intakes that would meet the needs of a mature cow in mid-gestation. [ABSTRACT FROM AUTHOR]

Cows fed diets consisting primarily of stored forages and concentrates may be at risk for vitamin A deficiency because these feedstuffs are low in ß-carotene. Furthermore, dietary vitamin A concentrations of the cow during late gestation will affect vitamin A concentrations in colostrum, which calves rely on at birth to supply vitamin A. The objective of this study was to evaluate how level of vitamin A supplementation from mid-gestation to early lactation affected cow and subsequently, liver retinol concentrations of their calf. Multiparous beef cows (n = 54) were stratified by body condition score and previous source and assigned to pen (n = 9); 3 pens were assigned to each of the following treatments: current NASEM recommendation (31,000 IU/d; 1X), 3 times (93,000 IU/d; 3X), or 5 times (155,000 IU/d; 5X) the current NASEM recommendation for supplemental vitamin A. Cows were limit-fed a diet consisting of wheat straw, corn silage, and wet distillers grains. Liver biopsies were collected on cows 3 weeks before treatment initiation, d 40 and d 81 of supplementation, and both cows and calves were sampled 32 days post-calving (165 ± 22 d SD of supplementation). No differences (P=0.86) in initial cow liver retinol (mean 186 μg/g DM) were observed between treatments. A significant treatment × day interaction (P < 0.01) was observed for cow liver retinol. On d 40, cows in 1X had liver retinol concentrations (178 μg/g DM) that were not different (P = 0.12) from 3X (213 μg/g DM) but less (P = 0.02) than 5X (241 μg/g DM), while 3X and 5X did not differ (P = 0.21). Liver retinol on d 81 was less (P < 0.05) in 1X (189 μg/g DM) compared with 3X (334 μg/g DM) and 5X (412 μg/g DM), which did not differ (P = 0.20). For cow liver retinol post-calving, 1X (187 μg/g DM) was less (P< 0.05) than 3X and 5X, and 3X (454 μg/g DM) was less (P< 0.05) than 5X (674 μg/g DM). Liver retinol concentrations of 1X cows remained below adequate reference ranges (300-700 μg/g of DM) throughout the study, whereas 3X and 5X were increased into the adequate range by d 81. Calf liver retinol concentration also differed among treatments (P = 0.01), as calves of cows in 1X had less (P < 0.05) liver concentrations than 3X and 5X calves which did not differ (P=0.12). Liver retinol concentrations considered adequate for calves at 32 days of age (100-350 μg/g of DM) were not observed in 1X calves (51 μg/g DM) but were observed in calves from 3X and 5X cows (119 and 165 μg/g DM, respectively). Supplementing cows with 93,000 IU/d of vitamin A for 165 days brought liver retinol concentrations of cows and their calves up within adequate reference ranges. [ABSTRACT FROM AUTHOR]

In the young calf, vitamin A is particularly important for immune system maturation, and calves rely on colostrum at birth to supply vitamin A. Cow vitamin A status may influence colostral vitamin A concentrations, which can impact vitamin A status of their calves. Very little is understood about this relationship between beef cow and calf vitamin A status. Furthermore, limited data is available on how plasma and liver retinol concentrations in cattle are related to one another. The objective of this study was to examine relationships between liver and plasma retinol concentrations in the cow, calf, and within cowcalf pairs. Multiparous MARC II beef cows (n = 120; 6.4 ± 1.2 SD years of age; 592 ± 58 SD kg BW) in mid-gestation were provided supplemental vitamin A as retinyl acetate in a supplemental pellet at a rate of 21,125 ± 8,560 SD IU/d (current NASEM recommendation = 33,000 IU/d). Cows were individually fed using Calan gates a diet consisting of alfalfa hay, corn silage, and supplemental pellet for 144 d (111 d pre-calving and 32 d post-calving). Basal diet vitamin A concentration was 490 IU/kg of DM. Mean initial liver concentration of cows was 830 μg retinol/g of DM. To assess vitamin A status, liver biopsies and plasma samples were collected on cows and calves at the end of the supplemental period when calves averaged 32 ± 7 days of age (DOA). Pearson correlations were used to test for linear relationships between cow liver and plasma retinol concentrations, calf liver and plasma retinol concentrations, and liver and plasma retinol concentrations between the cow and her calf. No linear relationship (P = 0.10; r=0.16) was observed between liver and plasma retinol in cows. In the present study, mean cow liver retinol concentration (482 ± 182 SD μg/g of DM) fell within the current adequacy reference range of 300–700 μg/g of DM. Cow plasma retinol (272 ± 40 SD ng/mL) was slightly below the reference range of 300–800 ng/mL. A positive correlation (P < 0.01; r=0.37) was detected between calf liver (51 ± 27 SD μg/g of DM) and plasma (190 ± 47 ng/mL) retinol concentrations. Both were below what would be considered adequate (100–350 μg/g of DM in liver; 225–325 ng/mL in plasma) for calves at 32 DOA. There was a positive correlation (P < 0.01; r=0.31) between cow and calf liver retinol, suggesting that as cow retinol liver concentrations increased, calf liver retinol concentrations increased. It appears that despite cows having adequate liver retinol concentrations when 21,125 IU vitamin A/d was fed, it did not result in calf liver retinol stores that would be considered adequate given current reference ranges. USDA is an equal opportunity employer and provider. [ABSTRACT FROM AUTHOR]

Conversion of perennial grasslands to crop land in U.S. Northern Plains has resulted in a need to evaluate alternative management strategies for cow-calf production. A 3-yr study was conducted to compare beef cow/calf performance in two different August-calving cow systems. Multiparous beef cows (n = 318) were allocated to 8 replicates, and replicate was randomly assigned to drylot (DL) or pasture (PAST) treatments. From mid-gestation (March/April) until breeding (October), DL cows were limit-fed to meet requirements and PAST cow grazed perennial pasture. Feed resource during the 47-d breeding period (November/December) varied by year and treatment. However, pregnancy rates did not differ (P=0.72) between treatments within year. Both treatments went to corn residue at the time of weaning (late January) and grazed for 37 d. A treatment × year × time interaction (P<0.01) was observed for cow BW, BCS, and calf BW. In Year 1, cow BCS at pre-calving, breeding, and weaning was less (P<0.01) for DL (5.3) than PAST (6.2; 1 to 9 scale). Weaning weights in Year 1 were less (P<0.05) for DL (178 kg) than PAST (183 kg) calves. In Year 2, cow BCS was less (P<0.01) in DL (6.1) than PAST (6.7) at pre-calving and breeding, but did not differ (P=0.12) at weaning. At weaning in Year 2, calf BW of DL (212 kg) was greater (P<0.01) than PAST (201 kg). Like Year 2, DL cows in Year 3 had decreased (P<0.01) BCS at pre-calving compared with PAST (7.3 vs. 7.7). However, breeding BCS (6.8) did not differ (P=0.98). In Year 3, cow BCS at weaning was greater (P<0.01) for DL (7.1) than PAST (5.9) but calf BW at weaning did not differ (P=0.17). Cow and calf performance are not sacrificed in semi-confined cow-calf systems and are a reasonable alternative to traditional pasture systems. [ABSTRACT FROM AUTHOR]

Simple Summary: Often the forage alone does not provide enough trace minerals to meet the needs of grazing cows and their calves, specifically copper and zinc are almost always deficient, with Se varying among geographical locations. The trace mineral status of cows can affect their ability to get and stay pregnant as well as the health of their calf in early life. Injectable trace minerals can provide additional supplemental trace minerals and allow for a known amount of trace minerals to be delivered to each animal. The objective of this trial was to determine the effects of a trace mineral injection on the trace mineral status of cows and calves and the resulting impacts on the reproductive performance of the cows and the growth of their nursing calves. In this study, use of an injectable trace mineral increased the cow's trace mineral stores, but the non-injected cows had adequate copper and zinc status due to free-choice mineral consumption, and no performance benefits of an injectable trace mineral were observed. The objective was to determine the effects of an injectable trace mineral (TMI; Multimin 90) containing copper (Cu), manganese (Mn), selenium (Se), and zinc (Zn) on trace mineral status and the resulting impacts on reproduction of beef cows and the growth of their calves. Beef cows (n = 200) were assigned to receive TMI or no injection (CON) prior to calving and breeding over two consecutive years. Calves born to cows receiving TMI also received TMI at birth in both years and at 49 ± 1.3 days of age in year 1. The TMI increased (p = 0.01) liver Zn and tended (p = 0.06) to increase liver Cu concentrations. Short-lived effects of TMI on Se were observed. Liver Cu and Zn would have been considered adequate and Se marginal in the CON. Pregnancy due to artificial insemination and overall pregnancy rate did not differ (p ≥ 0.36) between treatments. Use of TMI did not increase calf pre-weaning gain. These data indicate that TMI does not improve the reproductive performance of beef cows with adequate trace mineral status or the pre-weaning performance of their calves. [ABSTRACT FROM AUTHOR]

A two-yr study was conducted to measure reproductive responses of an alternative cow-calf production system. Multiparous, crossbred cows (n = 160; average age = 5.7 ± 2.8 yrs-old) were utilized, per yr, in a generalized randomized bock design and unstructured treatment design. In yr one, cows were blocked by origin source and age, randomly assigned to one of two production systems, each with four replicates (n = 20 cows/rep). Once allotted to treatment and replicate, cows remained in assigned treatment for the duration of their productive life. Treatments were: 1) traditional extensive spring calving system utilizing perennial pasture and corn residue grazing (TRAD); 2) alternative fall-calving system utilizing confinement, summerplanted oats, and corn residue grazing (ALT). Breeding body condition score (BCS) was greater (P < 0.01) for TRAD compared to ALT (6.45 vs. 5.47 ± 0.159, respectively). There were no differences (P ≥ 0.24) in conception rates (93.86 vs. 94.14 ± 2.26 %), pregnancy loss (4.37 vs. 5.62 ± 1.86 %), calving rates (89.50 vs. 88.49 ± 3.06 %), and weaning rates (86.88 vs. 82.50 ± 3.08 %) for TRAD and ALT, respectively. There was no difference (P = 0.47) in calf body weight at birth (40 vs. 39 ± 1.0 kg) for TRAD and ALT, respectively. Weaning BCS was greater (P < 0.01) for TRAD compared to ALT (5.71 vs. 5.27 ± 0.048). Calves in the TRAD system had greater (P < 0.001) wean BW (237 vs. 185 ± 3.7 kg) compared to ALT calves. Cows from TRAD system had greater (P < 0.001) kg weaned per cow exposed to bulls (208 vs. 151 ± 6.3 kg) compared to ALT cows. Results indicate no difference in reproductive performance among systems. The extensive spring-calving system produced heavier calves at weaning, leading to more kg of calf weaned per cow exposed. [ABSTRACT FROM AUTHOR]

To determine the effects of harvest method and ammoniation (3.7% of DM) on the consumption and waste of baled corn residue, a 6 x 6 Latin square with a 3 x 2 factorial treatment structure was conducted. Six treatments consisted of either untreated or ammoniated residue, harvested one of three ways: conventional rake-and-bale (CONV), New Holland Cornrower with two rows of stem chopped into the windrow with tailings (2ROW), or EZ-Bale system (EZB) with a disengaged combine spreader and tailings dropped in a windrow. Open beef females (12 heifers and 30 cows) were stratified and blocked by age into 6 pens (7 hd/pen) such that each pen had similar total BW. One bale was fed to each pen over six, 7 d periods using round-bale ring feeders with closed bottom panels. Residue falling around (waste) and remaining in (orts) the feeder were weighed. There was a significant (P < 0.01) harvest method by ammoniation interaction for DMI (% BW) and a tendency (P = 0.07) for waste. Intake of non-ammoniated EZB (1.6%) was greater (P = 0.03) than CONV (1.3%) and 2ROW (1.4%) which did not differ (P = 0.80). Intake of ammoniated CONV (1.2%) and EZB (1.5%) did not differ (P = 0.45) from their non-ammoniated counterpart, but ammoniation increased intake of 2ROW (1.9%). Within the unammoniated residue, waste did not differ (P > 0.13) among harvest methods and was 17.8%, 23.4%, and 22.7% for EZB, CONV and 2ROW. Ammoniated EZB (16.3%) and CONV (21.8%) did not differ from each other or their unammoniated counterpart. However, waste (10.6%) of ammoniated 2ROW was less (P < 0.01) than non-ammoniated 2ROW. Ammoniation and, to a lesser extent, harvest method, can be used to increase intake and reduce waste of corn residue bales fed to cows. [ABSTRACT FROM AUTHOR]