Evaluation of Level of Milk Potential on Nutrient Balance in 2- and 4- Year- Old May- Calving Range Cows Grazing Sandhills Upland Range

A modeling study evaluated the effects of milk production level on nutrient balance in May- calving cows grazing Sandhills upland range during the breeding season. Forage quality of upland range peaks in June and steadily declines in July until November. With timing of forage quality decline and increasing nutrient demands due to lactation, cows were in a negative energy balance in late June and early July prior to deficiency of metabolizable protein. Supplementation to meet energy deficiencies in June and July and MP deficiencies in July with distiller grains that is high ruminally undegradable protein and high fiber energy may be needed in May- calving cowherds. Selection for milk over 23 lb at peak lactation creates deficiencies early post- calving and increases the need for additional supplementation to correct the nutrient deficiency. In an effort to match cow type to environment in the Sandhills and optimize performance, producers should consider selecting against high milk potential

Evaluation of Level of Milk Potential on Nutrient Balance in 2- and 4- Year- Old May- Calving Range Cows Grazing Sandhills Upland Range

A modeling study evaluated the effects of milk production level on nutrient balance in May- calving cows grazing Sandhills upland range during the breeding season. Forage quality of upland range peaks in June and steadily declines in July until November. With timing of forage quality decline and increasing nutrient demands due to lactation, cows were in a negative energy balance in late June and early July prior to deficiency of metabolizable protein. Supplementation to meet energy deficiencies in June and July and MP deficiencies in July with distiller grains that is high ruminally undegradable protein and high fiber energy may be needed in May- calving cowherds. Selection for milk over 23 lb at peak lactation creates deficiencies early post- calving and increases the need for additional supplementation to correct the nutrient deficiency. In an effort to match cow type to environment in the Sandhills and optimize performance, producers should consider selecting against high milk potential

Profitability of Developing Beef Heifers on Stockpiled Winter Forages

We estimate the profitability of developing heifers on one stockpiled cool-season grass and two stockpiled warm-season grasses during the winter months by comparing distributions of net present value (NPV) over an 11-year useful life. Furthermore, distributions of payback period and the break-even price for each calf over the heifer’s production life were generated for each forage species. These results are compared across forages as well as to a simulated drylot system for heifer development. Data comes from a grazing experiment in Tennessee, where heifers grazed big bluestem and Indian grass combination (BBIG), switchgrass (SW), or endophyte-infected tall fescue (TF) pastures. Total cost of producing the first calf from a heifer using the three forage-based systems was $1,079/ head to$1,149/head, with TF being the most expensive forage-based heifer development system, and the total cost to produce a calf from heifers developed in a drylot system ranged from $574 to$644/head higher than the forage-based systems. The NPV of heifers developed on forage ranged from $264 to$468/head, while heifers developed in a drylot system had an NPV of –$876/head. Payback period was estimated in years of age, and heifers in forage-based systems became profitable at 3–4 years of age, whereas heifers developed in a drylot were 9–10 years of age before they covered their investment cost. The results indicate that SW was the lowest risk and the most profitable forage species relative to TF. These findings suggest that low-input forage-based systems may be more profitable than drylot heifer development systems in the southeastern United States

Impact of Cow Size on Cow-Calf and Subsequent Steer Feedlot Performance

This study retrospectively evaluated the effect of cow size on cow-calf performance and post-weaning steer feedlot performance of cows at the Gudmundsen Sandhills Laboratory, Whitman. Cows were categorized at small, medium, or moderate within cow age from 13 years of data. Small cows had decreased reproductive performance, weaned smaller calves, and produced steer progeny with smaller carcass weights. In this dataset and under the environmental and management conditions at Gudmundsen Sandhills Laboratory, overall productivity of the cowherd decreased as cow size decreased with 1,150 to 1,200 lb cow being the most productive cow size

Impact of cow milk production on cow–calf performance in the Nebraska Sandhills

Livestock producers have tended to select for increased output traits like milk production and growth to increase productivity. Even with the increased selection for greater calf growth potential, some regions in the United States have seen a plateau in calf body weight (BW) at weaning (Lalman et al., 2019). When focusing on reaching maximum potential of these output traits, it is important to consider the multitude of variables that affect a production system. With increased milk production, nutrient requirements for cows become increased (Ferrell and Jenkins, 1984; Montaño-Bermudez et al., 1990), which may not be met if range and forage availability for grazing is already limited at meeting lactation demands. Historically, weaning weight and milk production have been associated with a positive relationship with greater milk production resulting in heavier calves at weaning (Clutter and Nielsen, 1987; Abdelsamei et al., 2005). In contrast, others have only observed the benefit of increased milk production improving calf performance within the first 60 d after birth (Clutter and Nielsen, 1987; Ansotegui et al, 1991; Edwards et al., 2017). Gleddie and Berg (1968) reported the correlation between average daily gain (ADG) of calves and milk yield estimates increased between the first and second month and continued to decrease thereafter as the forage consumption increased. The reliance on milk for dietary energy can result in increased calf BW at peak lactation (Edwards et al., 2017), but benefits of increased milk production may decrease as stage of lactation increases. Our hypothesis was that increasing milk production would negatively affect cow reproductive performance while having no effect on calf performance. Therefore, the objective of this study was to determine the impact milk production has on subsequent cow reproductive performance and calf performance throughout the preweaning and postweaning phases

Impact of cow milk production on cow–calf performance in the Nebraska Sandhills

Livestock producers have tended to select for increased output traits like milk production and growth to increase productivity. Even with the increased selection for greater calf growth potential, some regions in the United States have seen a plateau in calf body weight (BW) at weaning (Lalman et al., 2019). When focusing on reaching maximum potential of these output traits, it is important to consider the multitude of variables that affect a production system. With increased milk production, nutrient requirements for cows become increased (Ferrell and Jenkins, 1984; Montaño-Bermudez et al., 1990), which may not be met if range and forage availability for grazing is already limited at meeting lactation demands. Historically, weaning weight and milk production have been associated with a positive relationship with greater milk production resulting in heavier calves at weaning (Clutter and Nielsen, 1987; Abdelsamei et al., 2005). In contrast, others have only observed the benefit of increased milk production improving calf performance within the first 60 d after birth (Clutter and Nielsen, 1987; Ansotegui et al, 1991; Edwards et al., 2017). Gleddie and Berg (1968) reported the correlation between average daily gain (ADG) of calves and milk yield estimates increased between the first and second month and continued to decrease thereafter as the forage consumption increased. The reliance on milk for dietary energy can result in increased calf BW at peak lactation (Edwards et al., 2017), but benefits of increased milk production may decrease as stage of lactation increases. Our hypothesis was that increasing milk production would negatively affect cow reproductive performance while having no effect on calf performance. Therefore, the objective of this study was to determine the impact milk production has on subsequent cow reproductive performance and calf performance throughout the preweaning and postweaning phases

Effect of Age of Dam on Heifer Progeny Performance

Cattle records were gathered and evaluated over a 12- yr period to investigate how cow age impacts heifer progeny growth and reproductive performance. Cow records from March and May calving herds, were categorized into young, moderate, and old groups based on their age at calving each year in the herd. Heifer calves born to young cows had lighter body weight at birth and adjusted 205- d BW than heifers from moderate and old cows. Heifer pre-breeding BW and pregnancy determination BW were not influenced by dam age. However, age of dam does impact the percentage of heifers to reach puberty prior to the start of breeding with no differences in percentage of heifers who calved within the first 21 d of calving in the subsequent calving season and pregnancy rates. Average number of calf crops from heifer progeny was different among all age of dam groups with young dams having more calves. Results from this study suggest older cows have a positive influence on growth and pre-breeding puberty status in female progeny during heifer development. Heifer progeny from young dams, however, had increased calf crops and longevity within the cowherd

The Effect of Cow Udder Score on Subsequent Calf Performance in the Nebraska Sandhills

Cow records were evaluated over a 5-yr period to investigate how cow udder score affected calf growth and carcass performance. Cows from 2 calving herds, March and May, were classified as bad or good based on udder scores recorded at calving. Calves suckling dams with bad udders performed similarly during the pre-weaning period to good udder counterparts, with no differences in overall steer feedlot performance between udder groups. However, steers suckling good udder cows had heavier carcass weights and greater back fat thickness

Perennial Warm-Season Grass Forages Impact on Cow-Calf Profitability in the Fescue Belt

Incorporating a perennial warm- season grass (WSG) into tall fescue (Lolium arundina-ceum [Schreb.] Darbysh.) forage systems in the fescue belt can help avoid the effects of fescue toxicosis on beef cattle (Bos taurus) reproduction and animal performance and provide forage during summer when fescue production is low. However, little information is available on the economics of incorporating WSG into fescue-based forage systems. We developed a simulation model to compare profitability of three forage systems—100% tall fescue, 70% tall fescue/30% bermudagrass (Cynodon dactylon), and 70% tall fescue/ 30% switchgrass (Panicum virgatum)—while also comparing spring- and fall-calving sea-sons on model beef cattle cow-calf operations in the fescue belt. Incorporating switch-grass increased profitability of tall fescue forage systems in both spring- and fall- calving herds, while adding bermudagrass increased profitability in spring-calving herds but not fall-calving herds. Spring-calving herds benefited the most from incorporating WSG, with profitability increases of $877 and$372 per hectare for switchgrass and bermudagrass, respectively, over the 100% tall fescue system. The order of profitability of forage systems did not change with randomly simulated decreases in rainfall and associated increased hay- feeding days, but with annual rainfall \u3e88% of the long- term average, fall- calving 100% tall fescue was more profitable than fall- calving 70% tall fescue/30% bermuda grass. Of the scenarios modeled, the results of the simulation suggest that a profit-maximizing producer would utilize a 70% tall fescue/30% switchgrass forage system