Dairy Resources - Management

October 2023

Abstract

Crossbreeding dairy cows with beef sires has increased in the U.S. dairy industry. This beef x dairy mating results in dairy-beef which has altered the U.S. fed beef supply. The predominant mating has been Holstein x Angus, thus research was conducted to determine the effects of Holstein x SimAngus breeding on growth performance, carcass characteristics, and fresh meat quality. Starting on d 1, Holstein steers (n = 9) and Holstein x SimAngus (HolSim) steers (n = 12) were fed once daily at 0830 h, until an end weight of 635 kg was reached. Holstein steers averaged 421 d and HolSim steers averaged 432 days on feed. Daily feed offered was delivered into a semi-autonomous feed monitoring system designed to measure individual animal intake and feeding behavior (GrowSafe System Ltd). Steer body weight was recorded every 28 d. Data collected were used to calculate dry matter intake (DMI), average daily gain (ADG), and gain to feed ratio (G:F). Steers were humanely slaughtered under USDA inspection, immediately following slaughter hot carcass weight (HCW) was recorded and 48 h following slaughter, carcass length, body width, backfat thickness and area of the longissimus muscle (LM) was recorded. Strip loins were collected from each carcass and aged for 14 d. After aging, Warner-Bratzler shear force (WBSF) and slice shear force (SSF) were determined. Remaining steaks were placed under retail display for 7 d. Objective color was measured after 0, 1, 3, 5, and 7 d in retail display. No differences were observed for ADG and G:F between Holstein and HolSim steers (P > 0.05). A tendency was observed for Holstein steers to have a greater DMI compared with HolSim steers (P = 0.0646). The HolSim steers had greater HCW and dressing percentages compared with Holstein steers (P < 0.0001). The HolSim carcasses had shorter carcass lengths and body widths compared with Holstein carcasses (P = 0.0005). Holstein carcasses had less backfat compared with HolSim carcasses (P = 0.0034). The LM area was larger in HolSim carcasses (P < 0.0001). No differences were observed for WBSF or SSF (P > 0.05). Strip steaks from HolSim steers had less deoxymyoglobin and greater oxymyoglobin values on d 0 of retail (P < 0.05). Strip steaks from HolSim steers had greater a* and saturation index values on d 7 in retail (P < 0.05). Strip steaks from HolSim steers had decreased metmyoglobin values and greater oxymyoglobin values on d 7 in retail (P < 0.05). Thus, indicating strip steaks from HolSim steers had increased red color. Growth performance data in this study confirm previous literature reported when comparing dairy x dairy to beef x dairy steers. Carcass and fresh meat data suggest that Holstein x SimAngus steers had improved yield production compared with Holstein steers without a loss in quality when steers were fed to a weight constant end point.

Teagan Schnurbusch, Derek W Brake, Emily A Petzel, Zachary D Callahan, Scott E Poock, Bryon R Wiegand
Journal of Animal Science, Volume 101, Issue Supplement_2, November 2023, Pages 56–57, https://doi.org/10.1093/jas/skad341.061

August 2021

ABSTRACT

Global rising temperature is a considerable threat to livestock production and an impediment to animal welfare. In fact, the 5 warmest years on record have occurred since 2016. Although the effect of heat stress on lactating cattle is well recognized and extensively studied, it is increasingly evident that rising temperatures will affect dairy cattle of all ages and lactation states. However, the extent and consequences of this effect are less understood and often overlooked in the literature and dairy industry. Early-life experiences, such as exposure to hyperthermia, can have life-long implications for health and productivity. This review highlights the body of work surrounding the effects of heat-stress exposure in young dairy cattle, including the prenatal fetus (in utero), postnatal calves (preweaning), and growing heifers, which are all categories that are typically not considered for heat-stress abatement on farm. Insights into the physiological and molecular mechanisms that might explain the adverse phenotypic outcomes of heat-stress exposure at different stages of development are also discussed. The estimated economic loss of in utero hyperthermia is addressed, and the ties between biological findings and opportunities for the application of cooling management interventions on farm are also presented. Our research highlights the importance of heat-stress abatement strategies for dry-pregnant cows to ensure optimal multigenerational productivity and showcases the benefits of cooling neonatal calves and growing heifers. Understanding the implications of heat stress at all life stages from a physiological, molecular, economic, and welfare perspective will lead to the development of novel and refined practices and interventions to help overcome the long-lasting effects of climate change in the dairy industry.

Jimena Laporta
DOI:https://doi.org/10.3168/jds.2021-20722

November 2023

Despite relatively low lameness prevalence, many New Zealand farmers believe it is an issue on their farm and they rank welfare impact of lameness of high importance. Photo: Canva

Understanding what motivates and prevents behavioural changes in farmers is a critical step in disease control in dairy cattle.

November 2023

Manure liquid can be spread on the soil, or injecting the manure into the soil decreases odours.

Dairy production intensification has various economic benefits for rural communities; however, it has negative environmental and public health impacts due to ineffective manure management. This article will consider 3 manure management systems in the dairy industry.

October 2023

Researchers have developed a new method of detecting the disease through linking data from the analysis of a cow’s milk with other information about the cow to predict future progression in the animal’s health. Photo: Canva

Around 3-quarters of diseases in dairy cows typically occur in the first month after calving, while around 50% of dairy cows experience some sort of diseases during the transition period. Researchers have developed a new method of detecting the disease through linking data from the analysis of a cow’s milk.

So, improving transition management and minimising the effect of immune suppression, hypocalcemia, and negative energy balance provides a large opportunity to decrease disease and increase the welfare and productivity of the herd.

October 2023

When diet crude protein levels are too low, cow performance can be reduced if the cow’s metabolisable protein requirements are not met. Photo: Chris McCullough

Dairy farmers trying to increase the nitrogen efficiency of their herds have been urged to fully analyse forage on the farm before decreasing protein content of feed.

As dairy cow diets contain nitrogen, mostly in the form of protein, the percentage of nitrogen consumed by the cow, and which subsequently ends up in milk protein, is defined as nitrogen use efficiency.

Research by Agri-Food and Biosciences Institute (AFBI) in Northern Ireland has shown the average nitrogen use efficiency by dairy herds to be low at around 30%. Most of the remaining 70% nitrogen is therefore excreted in manure, and part of this manure nitrogen can be lost to the environment during housing, manure storage and field spreading.

April 2023

ABSTRACT

Insufficient dry matter intake (DMI) of pasture by dairy cattle is a major factor limiting growth and milk production; however, it has been hypothesized that some dairy breeds may be more efficient grazers than others. This study was conducted to determine whether dairy breed types differ in DMI and feed efficiency when grazing either grass monoculture or grass-legume mixed pastures. The experiment compared 4 different dairy breed types (Jersey, Holstein, Holstein-Jersey crossbreds, and Montbéliarde-Swedish Red-Holstein 3-breed crossbreds) and 2 levels of pasture type [grass monoculture (MONO) and grass-birdsfoot trefoil (BFT) mixture (MX)] for a total of 8 treatments. Pastures were rotationally stocked with groups of 4 prepubertal heifers for 105 d for 3 yr, and DMI was determined from herbage disappearance. Feed conversion efficiency (FCE) and residual feed intake (RFI) were then derived from DMI, and heifer body weights (BW) and normalized to animal units (AU) as 40% metabolic mature BW of the corresponding dairy breed type to account for inherent differences in size and growth rates. We observed differences in DMI and feed efficiency among breed types and between pasture types. On average, Holsteins had the greatest overall DMI (4.4 kg/AU), followed by intermediate DMI by the crossbreds (4.0 kg/AU), and Jerseys had the least DMI (3.6 kg/AU). Heifers grazing MX pastures had on average 22% greater DMI than those grazing MONO, but heifers on grass monocultures were more efficient in converting DMI to BW gain (i.e., RFI/AU of 0.27 and −0.27, respectively; more negative RFI numbers indicate less DMI to achieve the expected gains). Overall, Jerseys had the most favorable feed efficiency; however, ranking of Holsteins and crossbreds depended upon the feed efficiency metric. This study is one of the first to compare the interaction of dairy breed and pasture quality on grazing efficiency. However, the lack of a breed type × pasture type interaction for DMI, FCE, or RFI indicated that none of these dairy breed types were better adapted than another breed type to pastures with contrasting levels of nutritive value.

Michael S. Greenland, Blair L. Waldron, S. Clay Isom, Jacob A. Hadfield, Bracken Henderson, J. Earl Creech
Journal of Dairy Science, DOI:https://doi.org/10.3168/jds.2022-22858

January 2023

Commercial products containing immunoglobulin G (IgG) sourced from colostrum, milk, and/or serum may be used to supplement or replace maternal colostrum in newborn dairy calves. To determine if antibody specificities in bovine milk and serum IgG differ from colostrum IgG, we sampled serum, colostrum (1 to 2 hours post-partum), and milk (day 5 post-partum) from 24 dairy heifers or cows. Specific antibodies [IgG class (H&L)] to 8 common pathogens were measured using enzyme-linked immunosorbent assays (ELISAs). Immunoglobin G1 and IgG2 subclass-specific ELISAs were performed for 3 of these pathogens. Colostrum-derived IgG contained more specific antibodies to rotavirus [IgG (H&L) and IgG1] and to IgG (H&L) of bovine respiratory syncytial virus (BRSV), bovine parainfluenza-3 virus (BPI3V), Staphylococcus aureus, Escherichia coli F5 (K99), and bovine coronavirus than milk IgG. Colostral IgG contained more antibodies to BRSV (IgG1), rotavirus (IgG1), and IgG (H&L) specific for BRSV, bovine herpesvirus-1 (BHV-1), BPI3V, E. coli F5 (K99), and Streptococcus uberis than serum IgG. Compared to serum, milk contained more IgG (H&L) antibody to BRSV, BHV-1, and BPI3V, IgG1-specific BRSV, and rotavirus. These data indicate that IgG derived from colostrum delivers more specific antibodies to these endemic pathogens of calves compared to IgG sourced from milk or serum. In addition, the IgG1 subclass predominates in milk and colostrum, and both deliver a similar spectrum of antibodies.

S. Lacoste*, J. Ellis M. Campos, D. Ramsay, D. Haines
Can J Vet Res
Vol. 87, No. 1, pp. 35-40

* Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4

Abstract:

Longevity and herd turnover rate are becoming common topics of discussion as the dairy industry strives for continuous improvement in efficiency, profitability, animal welfare, and environmental sustainability. Having the most productive animal fill each slot on a dairy makes strategic replacement and the resulting herd turnover an important tool for producers. Dairy operations can be considered to have slots available to be occupied by cows. The number of slots available is governed by dairy characteristics including parlor size and facility design. With sustainability and profitability goals, producers should aim to fill each slot with the most productive animal. The advantages of a modest surplus of replacement heifers allowing for a higher herd turnover rate are examined and shown to improve herd profitability, enhance welfare, and reduce environmental impact. A model assuming constant demand for dairy foods is presented with increased herd turnover rate leading to more milk production per cow and reduced enteric methane emissions. This analysis demonstrates that all else being equal, raising more replacements (having a relatively higher herd turnover rate and decreased herd-level longevity) improves sustainability compared to management aimed at lower herd turnover rates. Understanding the drivers of herd turnover in dairy production has important implications for the components of one health: animal well-being, food production, and environmental stewardship. The present work examines one tool toward this goal, while the companion Currents in One Health by Nguyen et al, JAVMA, January 2023, takes a broader view of many aspects of dairy sustainability.

Blake T. Nguyen DVM, Kaitlyn R. Briggs DVM, MBA, Steve Eicker DVM, Michael Overton DVM, MPVM, and Daryl V. Nydam DVM, PhD
DOI: https://doi.org/10.2460/ajvr.22.10.0177
Volume/Issue: Volume 84: Issue 1, Online Publication Date: 09 Dec 2022

October 18, 2022

Abstract:

The economics of sensor-based management of dairy cow suboptimal mobility. By Edwardes et al., page 9682. Early detection and prompt treatment of cows with mild suboptimal mobility can improve farm profitability. Better and more frequent visual detection of mild suboptimal mobility is time-consuming and costly. With a bioeconomic simulation model, we evaluated the economic value of automatic suboptimal mobility detection sensors. Results from this study show that incorporating these sensors in a sensor-based suboptimal mobility management strategy can add economic value to the farm operation. Results also show that the economic value is sensitive to management strategy and sensor performance.

Francis Edwardes, Mariska van der Voort, Henk Hogeveen
Journal of Dairy Science, DOI:https://doi.org/10.3168/jds.2021-21726