Research Update: Energy Strategies for Dry Cows

This information was presented at the 2014 Cornell Nutrition Conference for Feed Manufacturers, organized by the Department of Animal Science In the College of Agriculture and Life Sciences at Cornell University. Softcover copies of the entire conference proceedings may be purchased at http://ansci.cals.cornell.edu/extension-outreach/adult-extension/dairy-management/order-proceedings-resources or by calling (607)255-4285

The secretome from bovine mammosphere-derived cells (MDC) promotes angiogenesis, epithelial cell migration, and contains factors associated with defense and immunity

Treatment of bovine mastitis with intramammary antibiotics is common, yet several concerns exist including failed efficacy for individual hosts or pathogens and the inability of approved drugs to revert mastitis-induced tissue damage to healthy tissue capable of returning to full milk production. These issues, in addition to aspects of public health such as accidental antibiotic residues in saleable milk and the potential for antimicrobial resistance, support the need to find alternative therapies for this costly disease. This study shows that the secretome, or collective factors, produced by mammosphere-derived cells (MDC) promotes angiogenesis, epithelial cell migration, and contains proteins associated with immunity and defense; all of which are necessary for healing damaged mammary gland tissue. Furthermore, we found that the MDC secretome remains effective after freezing and thawing, enhancing its therapeutic potential. Our results provide a foundation for further characterization of the individual secreted factors and the rationale for using the MDC secretome as a complementary treatment for bovine mastitis

Predicting Transition Cow Health and Performance-Use of Blood and Fecal Biomarkers for Herd-Level Evaluation and Diagnostics

This information was presented at the 2012 NEDPA Conference, organized by the PRO-DAIRY program in the College of Agriculture and Life Sciences at Cornell University. The Northeast Dairy Producers Association (NEDPA) Conference is designed for producers and agriservice professionals to interact and relate to the latest thinking and issues in the dairy industry. Softcover copies of the entire conference proceedings may be purchased at http://www.ansci.cornell.edu/dm/proceedings_orders.html or by calling (607) 255-4285

Validation of a mycoplasma molecular diagnostic test and distribution of mycoplasma species in bovine milk among New York dairy farms

Mycoplasma mastitis is a contagious and costly disease of dairy cattle that significantly affects animal health and milk productivity. Mycoplasma bovis is the most prevalent and invasive agent of mycoplasma mastitis in dairy cattle, and early detection is critical. Other mycoplasma have been isolated from milk; however, the role and prevalence of these species as mastitis pathogens are poorly understood. Routine screening of milk for mycoplasma by bacteriological culture is an important component of a farm control strategy to minimize a herd mycoplasma outbreak, but phenotypic methods have limited ability to speciate mycoplasma, affecting how farms and practitioners can understand the role and effect of species other than M. bovis in herd health. Fastidious mycoplasma culture can be lengthy and inconclusive, resulting in delayed or false negative reports. We developed and validated a multitarget PCR assay that can in the same day confirm or reject a presumptive positive mycoplasma culture found upon bacteriological testing of clinical specimens, further discriminate between Acholeplasma and Mycoplasma, and identify M. bovis. Coupled with sequence analysis isolates can be further identified as bovine mycoplasma Mycoplasma arginini, Mycoplasma alkalescens, Mycoplasma canadense, Mycoplasma bovirhinis, Mycoplasma bovigenitalium, Mycoplasma californicum, Acholeplasma laidlawii, and Acholeplasma oculi. Assay validation included analysis of 845 mycoplasma representing these species and 30 additional bacterial species obtained from routine milk submissions to the Quality Milk Production Services from New York farms and veterinary clinics between January 2012 and December 2015. Among 95 herds, we found 8 different Mycoplasma species and 3 different Acholeplasma species, with an overall prevalence of M. bovirhinis of 1%, A. oculi of 2%, M. arginini of 2%, M. californicum of 3%, M. canadense of 10%, M. bovigenitalium of 10%, A. laidlawii of 11%, M. alkalescens of 17%, and M. bovis of 78%. More than one mycoplasma was found in 14% of the herds tested, and both M. bovis and Acholeplasma were found in 6% of the farms. Incorporation of the validated molecular diagnostic assay into routine bacteriological screening as a supportive confirmation and identification tool will lead to an improved assessment of Mycoplasma and Acholeplasma prevalence data, which will facilitate increased knowledge about the role of these mycoplasma in mastitis

Transition cow nutrition and management strategies of dairy herds in the northeastern United States: Part III—Associations of management and dietary factors with analytes, health, milk yield, and reproduction

ABSTRACT: The objective was to evaluate relationships between putative periparturient management and dietary factors at the pen and herd levels with metabolic- and inflammation-related analytes, health disorders, milk yield, and reproductive performance. Multiparous and primiparous cows from 72 farms in the northeastern United States were enrolled in a prospective cohort study. Farms were visited 3 times during the prepartum and postpartum periods: during the far-off dry, close-up dry, and fresh periods. Pen measurements were taken at each visit for the pens where cows sampled were housed, and particle size was determined for the total mixed ration for the pen. A survey was used to acquire data on herd-level management variables. Blood samples were collected from the same 11 to 24 cows per farm during the close-up and fresh period visits. Whole blood was analyzed for postpartum β-hydroxybutyrate (BHB) concentrations, and plasma was analyzed for prepartum and postpartum nonesterified fatty acids (NEFA) and postpartum haptoglobin (Hp) concentrations. Health event, milk yield, and reproductive records were acquired through the records management software program used on the farm. For the pen-level analysis, primiparous and multiparous cows were analyzed separately. For the pen- and herd-level analysis, a simple linear regression was conducted on all possible explanatory variables. Variables were included in the full multivariable general linear model if P < 0.20, and a manual backward stepwise elimination process ensued until all variables had P < 0.10. Our results indicate that pen- and herd-level management factors are associated with blood biomarkers, health, milk yield, and reproductive performance. For the prepartum period, our results support increasing the proportion of particles on the 19-mm sieve of the Penn State Particle Separator, optimizing bunk space, and not overfeeding metabolizable energy (ME), to decrease the prevalence of elevated postpartum NEFA, BHB, and Hp concentrations, decrease disorder incidence, maximize milk yield, and improve pregnancy risk to first service. For the fresh period, our results generally support optimizing bunk space, avoiding commingling, increasing feeding frequency, avoiding high physically effective undigested neutral detergent fiber (NDF) after 240 h of in vitro fermentation and high total fermentable carbohydrate diets while optimizing the inclusion of forage NDF, and ensuring adequate diet ME and metabolizable protein to reduce the prevalence of elevated postpartum NEFA, BHB, and Hp concentrations, minimize disorder incidence, maximize milk yield, and improve pregnancy risk to first service. At the herd level, our results generally support not vaccinating in the calving pen, minimizing the number of prepartum and postpartum pen moves, and avoiding long stays in the calving pen after parturition to reduce the prevalence of elevated biomarker concentrations, decrease disorder incidence, increase milk yield, and improve reproductive performance

Relationships Between Transition Cow Nutrition and Management Strategies and Outcomes in Large Dairy Herds in the Northeastern US

Given an increase in nutrient requirements for milk production, decrease in DMI, parturition, management factors such as frequent pen moves, and diet changes, the transition period is arguably the most demanding time in a dairy cow’s life. The objectives of the first part of this study were 1) to establish thresholds for NEFA, BHB, and haptoglobin concentrations that are associated with disease, 2) evaluate the association between the biomarkers with milk production and reproductive performance, and 3) identify herd-alarm levels for the biomarkers that are associated with herd-level changes in disease, milk, and reproductive performance. In addition, limited field data exist that evaluate different management and nutritional strategies that contribute to cow success in commercial farm settings. Therefore, recommendations are often driven by field experience from concepts established through controlled research with comparatively small numbers of cows. The objective of the second part of this study wasto evaluate management and nutritional factors with outcomes on commercial farms, such as disease, prevalence of elevated biomarkers, milk production, and reproductive performance to provide an understanding of how these factors contribute to transition cow success across a range of farm practices

A randomized controlled trial to study the effects of an automated premilking stimulation system on milking performance, teat tissue condition, and udder health in Holstein dairy cows

ABSTRACT: The objectives were to examine the effect of an automated premilking stimulation (APS) by means of a high pulsation frequency (300 cycles/min) without a reduction of the vacuum in the pulsation chamber or claw piece on (1) milking performance, (2) teat tissue condition, and (3) udder health in dairy cows. In a randomized controlled field study, Holstein cows (n = 427) from 1 commercial dairy farm with a milking schedule of 3 times per day were assigned to treatment and control groups over a 90-d period. Treatments consisted of a maximum of 80 s (APS80) or 99 s (APS99) of mechanical stimulation at a pulsation rate of 300 pulses per minute and a ratio of 25:75 (no reduction of the pulsation chamber or milking vacuum). Cows in the control group (CON) received traditional premilking stimulation by means of manual forestripping for 8 s. Milking characteristics were documented with on-farm milk meters. Short- and long-term changes in teat tissue condition induced by machine milking were assessed visually on a weekly basis. Composite milk samples were analyzed once per month to determine somatic cell count. Generalized linear mixed models were used to study the effect of the treatment on the outcome variables. We observed no meaningful differences in milk yield or milking unit-on time. Least squares means and their 95% confidence intervals (95% CI) for cows in the APS80, APS99, and CON groups were 13.5 (13.1–14.0), 13.2 (12.8–13.7), and 13.2 (12.8–13.7) kg for milk yield and 222 (213–231), 219 (210–228), and 223 (214–232) s for milking unit-on time, respectively. The effect of treatment on bimodality was modified by milk yield such that the odds of bimodality increased in the treatment groups with increasing milk yield. Compared with cows in the CON group, the odds ratios (95% CI) of bimodality were 1.08 (0.62–1.89) in the APS80 group and 0.89 (0.55–1.42) in the APS99 group at a milk yield of 11 kg and 2.0 (1.24–3.22) in the APS80 group and 2.08 (1.29–3.35) in the APS99 group at a milk yield of 16 kg. We observed differences in short- and long-term changes in teat tissue condition between the treatment and control groups. Compared with cows in the CON group, the odds (95% CI) of short-term changes were 1.87 (1.35–2.58) for the APS80 group and 1.49 (1.08–2.07) for the APS99 group, and the odds of long-term changes were 1.52 (1.24–1.85) for cows in the APS80 group and 1.59 (1.31–1.94) for cows in the APS99 group. The least squares means (95% CI) for somatic cell counts (log10-transformed) were 4.74 (4.68–4.81) for the APS80 group, 4.77 (4.71–4.83) for the APS99 group, and 4.79 (4.73–4.86) for the CON group. We conclude that the APS system tested here had no negative effects on milk yield or milking unit-on time. However, differences in bimodality and teat tissue condition suggest that the APS system did not provide sufficient stimulation to facilitate a gentle milk harvest and adversely affects teat tissue condition

Association of herd-level risk factors and incidence rate of clinical mastitis in 20 Brazilian dairy herds

The objectives of this study were to characterize the pathogen frequency and severity of clinical mastitis (CM) in 20 dairy herds of southeastern Brazil; and to determine the incidence rate of clinical mastitis (IRCM; overall and based on specific-pathogen groups) based on quarter time at risk and its association with risk factors at the herd-level. Data were recorded in each herd for a period of 8 to 15 months. The association between herd-level risk factors and IRCM were determined by two groups of mixed regression models: one based on the overall IRCM, and five based on the following specific-pathogen groups: contagious, other Gram-positive, Gram-negative, other, and negative culture. The following herd-level risk factors were evaluated: herd size, housing system, average daily milk yield per cow, bulk milk somatic cell count (BMSCC), and bulk milk total bacterial count (BMTBC). A total of 5957 quarter-cases of CM were recorded from 2637 cows, but only 4212 cases had milk samples collected for culture. The most frequently isolated pathogens were Escherichia coli (6.6% of total cultures), Streptococcus uberis (6.1%), and Streptococcus agalactiae (5.9%). The majority of CM cases were mild (60.3%), while 34.1% were moderate and 5.6% severe. The frequency of severe CM cases was lower for those with a Gram-positive result (4.6%) compared to a Gram-negative result (11.4%). Overall, monthly mean IRCM was 9.7 cases per 10,000 quarter-days at risk (QDAR). Herds with a geometric mean BMSCC 65 601 7 103 cell/mL had higher overall IRCM (16/10,000 QDAR) than those with BMSCC 64 600 7 103 cell/mL ( 647.7/10,000 QDAR). When the specific-pathogen groups were evaluated, for contagious pathogens, variables housing (free-stalls or compost-bedded pack barns), BMSCC ( 65601 7 103 cells/mL), and average daily milk yield per cow (21 and 25 Kg/d) presented the highest IRCM. Furthermore, in Gram-negative group, herds with BMTBC 65 31 7 103 cfu/mL had higher IRCM compared with herds with BMTBC 64 30 7 103 cfu/mL. Although environmental pathogens were the most common cause of CM in this study, contagious pathogens (e.g., Strep. agalactiae and Staph. aureus) are still a concern in dairy herds of Brazil. Additionally, as there were some herd-level risk factors associated with the IRCM, there may be opportunity for management strategies aiming to improve the control of CM in dairy herds