Justin W. Waggoner

Phenotypic relationships between docility and reproduction in Angus heifers

The objective of this study was to elucidate the phenotypic relationships between docility and first-service AI conception rate in heifers. Data ( = 337) collected from 3 cooperator herds in Kansas at the start of synchronization protocol included exit velocity (EV), chute score (CS), fecal cortisol (FC), and blood serum cortisol (BC). Data were analyzed using logistic regression with 30-d pregnancy rate as the dependent variable. The model included the fixed effect of contemporary group and the covariates FC, BC, EV, CS, BW, and age. Correlation coefficients were calculated between all continuous traits. Pregnancy rate ranged from 34% to 60% between herds. Blood cortisol positively correlated with EV ( = 0.22, < 0.01), negatively correlated with age ( = -0.12, < 0.03), and tended to be negatively correlated with BW ( = -0.10, = 0.09). Exit velocity was positively correlated with CS ( = 0.24, < 0.01) and negatively correlated with BW ( = -0.15, < 0.01) and age ( = -0.12, < 0.03). Chute score negatively correlated with age ( = -0.14, < 0.01), and age and BW were moderately positively correlated ( = 0.42, < 0.01), as expected. Older, heavier animals generally had better temperament, as indicated by lower BC, EV, and CS. The power of our test could detect no significant predictors of 30-d pregnancy for the combined data from all ranches. When the data were divided by ranch, CS ( < 0.03) and BW ( < 0.01) were both significant predictors for 30-d pregnancy for ranch 1. The odds ratio estimate for CS has an inverse relationship with pregnancy, meaning that a 1-unit increase in average CS will reduce the probability of pregnancy at ranch 1 by 48.1%. Weight also has a negative impact on pregnancy because a 1-kg increase in BW will decrease the probability of pregnancy by 2.2%. Fertility is a complex trait that depends on many factors; our data suggest that docility is 1 factor that warrants further investigation.

Effects of Frequency of Protein Supplementation on Performance by Beef Calves Grazing Dormant Native Range

Stocker calves that graze forages before entering a feedlot account for more than 75% of the beef calves raised in the United States each year. A large proportion of those will be calves born in the spring and weaned in the fall. Modest growth rates are expected when the quality of fall and winter forages is poor. Growing calves in confinement systems during fall and winter typically allows for greater average daily gain (ADG) than grazing low-quality forages; however, modest overall costs associated with grazing perennial, dormant forages may be competitive during times when feed prices are relatively high. Providing supplemental protein to beef cows grazing dormant, warm-season, native forages (i.e., ≤ 6% crude protein [CP]) has been demonstrated to increase body condition score (BCS), body weight (BW), improve dry matter digestibility (DMD), and forage dry matter intake (DMI). Furthermore, beef cows grazing low-quality forages and supplemented with protein either daily, every third day, or every sixth day had similar BW and BCS. Reducing the frequency of supplement delivery can reduce labor costs and equipment depreciation without negatively affecting animal performance; however, this practice has variable success when used with growing beef cattle. In previous research, steers supplemented with cottonseed cake 3 times weekly had similar BW gain during winter compared to steers supplemented daily. Conversely, in another study, steers grazing winter range and supplemented with dried distillers grain daily had greater ADG than steers supplemented 3 times weekly. Therefore, the objective of this study was to evaluate the performance of young, lightweight stocker calves grazing dormant, native tallgrass pastures and supplemented protein either daily or 3 times weekly throughout the winter.

Effects of Early or Conventional Weaning on Beef Cow and Calf Performance in Pasture and Drylot Environments

During widespread drought, pasture availability and productivity are reduced. This, coupled with increasing land prices and lease rates, has prompted the evaluation of alternative management strategies that decrease grazing pressure on perennial pasture or reduce feed and pasture costs. Weaning early and moving cows from pasture to a drylot environment is used commonly for reducing grazing pressure on perennial pastures. A premature end to lactation reduces cow nutrient requirements and reduces grazing pressure. Removal of the calf further reduces grazing pressure, as calves are significant consumers of forage dry matter (DM) during mid and late lactation. The combination can be used to extend grazing by 0.4 d for each d weaning is executed earlier than normal. Early weaning may result in calves having less value at weaning compared to calves weaned at conventional ages. Retaining ownership of young calves through backgrounding can be useful for increasing their value. Limit-feeding non-lactating cows or cowcalf pairs in confinement can also reduce grazing pressure on pastures, while maintaining cow body condition score (BCS) or body weight (BW). Previous research conducted at the location of this study found that limit-feeding non-lactating cows at 1.9% BW achieved acceptable gains in BW, BCS, and rump fat. Therefore, the objective of our study was to evaluate the performance of beef cows and calves subject to a 56-d early or conventional weaning period in either pasture or drylot environments.

Performance of Beef Replacement Heifers Supplemented with Dried Distillers Grains or a Mixture of Soybean Meal and Ground Sorghum Grain

The feed, labor, and equipment costs of developing heifers in a confined feeding system are relatively high. High Plains beef producers can reduce input costs by developing heifers on dormant native range; however, heifers are typically unable to consume sufficient crude protein (CP) from the low-quality ( 30% CP). Traditionally, producers have used oilseed meals in this capacity, but with the expansion of the ethanol industry, dried distillers grains with solubles (DDG) have become widely available as an alternative protein source for producers in corn and sorghum-producing regions. Adequate heifer body weight and body condition score at first breeding are essential to minimize age at first calving and to increase lifetime productivity. Therefore, the objective of our study was to evaluate the effects of supplementation of DDG or an approximately isonitrogenous mixture of soybean meal and ground sorghum grain on growth and reproductive performance of replacement heifers grazing low-quality, dormant native range.

Effects of Altering Supplementation Frequency During the Pre-Partum Period of Beef Cows Grazing Dormant Native Range

Spring-calving beef cattle that are grazing low-quality ( 30% crude protein) is recommended to decrease losses of body weight and body condition. Nutrient supplementation when forage quality is poor or limited is one of the largest expenditures for forage-based beef cattle operations. The expansion of the ethanol industry has afforded many producers in corn and sorghum-producing regions an alternative to traditional oilseed-based protein supplements. The availability and nutrient profile of distiller’s grains with solubles (DDG) has made it popular as a supplement for cows that are grazing dormant low-quality forages. Decreasing supplementation frequency reduces costs for labor and fuel. Previous research has shown no difference in body weights or body condition scores of cows supplemented with distiller’s grains daily, once every three days, or once every six days; however, the proportion of cows that ate hay during the 60 minutes immediately after supplementation was less on the day of supplementation for cows supplemented once every six days compared to cows supplemented daily. The observed decrease in hay consumption following supplementation could potentially decrease total organic matter intake during late gestation. More frequent supplementation may increase organic matter intake and improve performance during the month before parturition. Therefore, the objective of this study was to evaluate effects of altering frequency of supplementing distiller’s grains during the last 28 days of gestation with respect to performance of spring-calving beef cows consuming low-quality dormant native range.

Performance of Beef Replacement Heifers Supplemented With Dried Distillers Grains With Solubles Versus a Mixture of Soybean Meal and Finely Ground Sorghum Grain

Costs of feed, labor, and equipment to develop heifers in a traditional confined feeding system are relatively high. Producers can greatly reduce input costs by developing heifers on dormant native range; however, heifers are unable to consume sufficient protein from the forage base. Suboptimal protein intake will reduce forage digestion and result in poor performance. Supplemental protein is required during these times to increase forage intake and digestion. The most efficient way of providing supplemental protein to heifers consuming lowquality ( 30% crude protein). Producers traditionally have used high-quality oilseed meals to supplement the necessary protein, but expansion of the ethanol industry has made dried distillers grains with solubles (DDGS) a potentially less expensive supplement option for producers in cornand sorghum-producing areas. The objective of this study was to evaluate the effects of daily supplementation of DDGS vs. a mixture of soybean meal and finely ground sorghum grain on performance of replacement heifers grazing low-quality dormant native range.

Relationships between docility and reproduction in Angus heifers

Introduction Reproductive success is relevant in beef cattle operations because income generated by the sale of calves is often a large portion of an operation’s income. Selecting for fertility is difficult because it is influenced by a variety of factors. Temperament could be a factor affecting fertility. Physiological responses associated with temperament can influence the probability of cows becoming pregnant because stress hormones in the bloodstream can negatively affect the release of reproductive hormones.

Wheat straw improved by half-rate application of anhydrous ammonia

Introduction Many tons of crop residues and other low-quality forages are produced in Kansas each year. Use of these forages often is limited by their low nutrient content and poor digestibility. The process of applying anhydrous ammonia to low-quality forages enhances their feeding value by increasing crude protein content and dry matter digestibility. In the summer of 2012, the persistence of drought conditions throughout Kansas reduced forage supplies and resulted in a dramatic increase in forage prices. In an effort to aid livestock producers, the K-State Beef Extension Specialist Team, in conjunction with the Livestock Production Program Focus Team, conducted wheat straw ammoniation demonstrations at 6 locations across Kansas. The objectives of these demonstrations were to: (1) demonstrate the process of using anhydrous ammonia to treat low-quality roughages, and (2) determine if the recommended rate of 3% anhydrous ammonia application (dry weight) could be decreased as a cost-saving measure. The effects of two anhydrous ammonia application rates (1.5 and 3.0% dry matter weight of stack, equivalent to 30 or 60 lb anhydrous ammonia/ton of dry forage) on subsequent forage quality and digestibility were evaluated.

Calf health and performance during receiving is not changed by fence-line preconditioning on flint hills range vs. drylot preconditioning

Introduction Ranch-of-origin preconditioning can improve the welfare and performance of beef calves by decreasing the stress associated with weaning, transport, diet change, and commingling with other calves. Preconditioning methods that involve pasture weaning coupled with maternal contact (i.e., fence-line weaning) have been promoted as possible best management practices for minimizing stress. Prior studies focused on performance and behavior during preconditioning on the ranch of origin. Little information has been published relating to carryover effects of fence-line preconditioning compared with conventional drylot preconditioning on performance and behavior during feedlot receiving.

Effects of infrequent dried distillers grain supplementation on spring-calving cow performance

Introduction Feed and supplement costs and the expenses associated with delivery of winter supplements account for a large proportion of the total operating expenditures for cow-calf producers. Cattle grazing low-quality dormant native range (<6% crude protein) typically are unable to consume sufficient protein from the forage base, which limits microbial activity and forage digestion. Supplemental protein often is required to maintain cow body weight and body condition score during the last trimester of pregnancy. Low cow body condition scores at calving are common and may negatively affect lactation, rebreeding rates, and calf weaning weight. Failure to maintain proper nutritional status during this period severely affects short-term cow performance, reduces overall herd productivity, and limits profit potential.