Richard T. Clark

Extended grazing systems for improving economic returns from Nebraska sandhills cow/calf operations

Three winter treatments were cross classified with 2 spring treatments to create 6 feeding and grazing systems utilizing Nebraska sandhills range and subirrigated meadow forage. Systems were evaluated with multiparous crossbred beef cows over 4 years (240 head beginning year 1). Systems were: 1) owing range during winter; 2) grazing subirrigated meadow during winter; and 3) fur feed of meadow bay during winter; in combination with either: a) full feed of subirrigated meadow hay during May, or b) grazing subirrigated meadow during May. From June through November all cows grazed range. The feeding and grazing systems were compared with selected linear contrasts and evaluated with respect to variable input prices. Some differences in cow body weight and body condition occurred but differences were considered small. Throughout the study, cows on all systems generally maintained a body condition score of about 5 (1 to 9 scale) year long. Inputs of hay were reduced by grazing range or subirrigated meadow during winter and during May without affecting pregnancy rate. Weaning weight of calves was increased 5.0 kg by grazing meadow during May compared to feeding hay during May. When opportunity costs were included in the analysis, the most profitable system involved grazing subirrigated meadow during winter and during May. Grazing subirrigated meadow during May enhanced the profitability of all wintering systems.

Effects of Weaning Date and Prepartum Protein Supplementation on Cow Performance and Calf Growth

Abstract Two experiments evaluated effects of weaning date on cow body condition score (BCS) and calf growth. In Experiment 1, 134 March-calving cows were used in a four-year experiment. Calves were weaned 18 August or 7 November and cows were fed 0 or 0.45 kg protein supplement (42% crude protein) three days per week from 1 December to 28 February while grazing upland range in a 2 by 2 factorial arrangement of treatments. In Experiment 2, spring calving cows (year 1, n = 97; year 2, n = 104) were assigned randomly to one of eight weaning dates at 2-week intervals from 19 August to 25 November. In Experiment 1, weaning in August increased cow BCS precalving (P < 0.001) and prebreeding (P < 0.001), but not pregnancy rates (P = 0.56). Cows fed supplemental protein had greater BCS precalving (P < 0.001) and prebreeding (P = 0.001) than nonsupplemented cows, but pregnancy rates were similar (P = 0.27). Calves born to cows fed supplemental protein prepartum had greater weaning weight than calves born to nonsupplemented cows regardless of whether weaning occurred in August (P = 0.001) or November (P < 0.001). Effects of weaning date on feedlot performance interacted with supplementation treatment. Calves born to cows fed supplement that were weaned in November generated the greatest net returns. In Experiment 2, BCS decreased linearly (P < 0.001) as date of weaning was delayed from August to November. Nursing calf gain increased cubically (P < 0.0004) and weaned calf gain from August to November increased quadratically (P < 0.002). Protein supplementation did not affect cow pregnancy rate, but calves born to cows fed protein supplement had greater pre- and postweaning gains. Cow BCS decreased as weaning date was moved later in the year but cow pregnancy rate was not affected by weaning date.

SYMPOSIUM PAPER: Economic and Tax Implications for Managing Beef Replacement Heifers 1,2

Abstract Sustainable cowherds require replacement of cull cows either internally via raised heifers or externally with purchased females. Managing raised replacements begins with a weaned heifer calf and continues on through her second pregnancy and calving. Replacement costs were estimated from research conducted in Nebraska for spring-calving cowherds and included the opportunity cost of the heifer calf. The analysis, based on research data, showed that heifer development programs targeted to 50 to 55% of mature BW (MBW) at first breeding can be successful, challenging the traditional target of 65% of MBW at first breeding. The lower BW programs achieved first-calf pregnancy rates near 90% of heifers exposed and resulted in development costs that were

First limiting nutrient for summer calving cows grazing autumn-winter range.

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Production and Economic Comparisons of Two Calving Dates for Beef Cows in the Nebraska Sandhills

30 per head lower than the higher BW programs. Finishing or selling open first-calf heifers was shown to be an economically viable enterprise given development costs were not too large. Numbers of open first-calf heifers were shown not to greatly affect total development costs. The primiparous heifer can increase the overall heifer development costs if not managed properly. Research showed that strategic nutritional programs for primiparous heifers resulted in successful reproduction without large increases in costs (

Symposium Paper: Economic and Tax Implications for Managing Beef Replacement Heifers12

Two trials were conducted in 1994, 1995, and 1996 to determine the first limiting nutrient for summer calving cows grazing Sandhills range. In Trial 1, 48 lactating summer calving cows grazing native range during the breeding season were assigned to 1 of 4 supplement treatments: 1) control-no supplement, 2) energy, 3) degradable intake protein (DIP), and 4) DIP + undegraded intake protein (UIP). Cows were group-fed supplements in 8 pastures (2 pastures/treatment). The trial began 4 September and ended 4 November each year. Diet samples from esophageally fistulated cows averaged 7.5% crude protein and 54.5% in vitro organic matter digestibility. Supplemented cows lost less body condition compared to control cows (P = 0.04). Cow and calf weight gains were increased by supplemental DIP or DIP + UIP combination compared to energy supplement (P = 0.09 and 0.08, respectively). Forage intake and digestibility were not different among treatments (P > 0.20). Milk production was lower for non-supplemented than supplemented cows (P = 0.10). Trial 2 began 5 November and ended 10 January in 1994-1995, 1995-1996, and 1996-1997. Treatments and pastures were the same as described in Trial 1, however, only 40 cows were used. In Trial 2, diet samples from esophageally fistulated cows averaged 6.2% crude protein and 52.3% in vitro organic matter digestibility. No differences (P > 0.10) in body condition score were detected. Total organic matter intake was lower for control compared to supplemented treatments (13.5 vs.15.5 kg day(-1); P < 0.10). We concluded that DIP was the first limiting nutrient for summer calving cows during the breeding season and during autumn-winter lactation after the breeding season.

Symposium Paper: Economic and Tax Implications for Managing Beef Replacement Heifers11A contribution of the University of Nebraska-Lincoln, Agricultural Research Division, Lincoln 68583. Jr. Series No. 14654.22Presented at the Extension Symposium at the Midwest American Society of Animal Science sectional meetings in Des Moines, IA on March 16, 2004. The symposium was sponsored by NCR-87, Committee on Cow-Calf Nutrition and Management.

ABSTRACT Calving date for 120 cows in the Nebraska Sandhills was changed from the traditional calving season beginning March 15 (d 75) to one beginning June 15 (d 167) to match increased nutrient needs for lactating cows to immature grazed forages that are high in protein and energy. The hypotheses being tested were that 1) less hay and purchased feeds would be required, 2) production costs would be reduced, and 3) net returns would be greater for June-calving cows compared with their March-calving counterparts. All steer calves from 75 March-calving cows were moved to a feedlot within 60 d of weaning (March calf-feds). Half the steer calves from the 120 June-calving herd were moved within 60 d of weaning to a feedlot to be finished (June calf-feds) and the other half were moved to a feedlot in September after summer grazing of Sandhills rangeland (June yearlings). Half of the June-calving cows were bred on subirrigated regrowth (Meadow) and half on upland range. Data on 4 consecutive calf crops were collected through harvest with an additional year collected to feedlot placement. Results showed that fed hay was reduced from 1.79 to 0.10 metric tons per cow annually for the June-calving system. Cost and return analyses were conducted by production phases on steer calves. Production costs for both June-calving groups were less and net returns higher when compared with the March-calved group. The highest net return for a calf group was for the June yearlings from cows bred on subirrigated regrowth.

Symposium PaperSymposium Paper: Economic and Tax Implications for Managing Beef Replacement Heifers12

Abstract Sustainable cowherds require replacement of cull cows either internally via raised heifers or externally with purchased females. Managing raised replacements begins with a weaned heifer calf and continues on through her second pregnancy and calving. Replacement costs were estimated from research conducted in Nebraska for spring-calving cowherds and included the opportunity cost of the heifer calf. The analysis, based on research data, showed that heifer development programs targeted to 50 to 55% of mature BW (MBW) at first breeding can be successful, challenging the traditional target of 65% of MBW at first breeding. The lower BW programs achieved first-calf pregnancy rates near 90% of heifers exposed and resulted in development costs that were

Cross Compliance for Erosion Control: Anticipating Efficiency and Distributive Impacts: Comment

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Age of calf at weaning of spring-calving beef cows and the effect on cow and calf performance and production economics.

30 per head lower than the higher BW programs. Finishing or selling open first-calf heifers was shown to be an economically viable enterprise given development costs were not too large. Numbers of open first-calf heifers were shown not to greatly affect total development costs. The primiparous heifer can increase the overall heifer development costs if not managed properly. Research showed that strategic nutritional programs for primiparous heifers resulted in successful reproduction without large increases in costs (