Benchmarking Reproductive Efficiency and Transition Cow Health of Kansas Dairy Herds

Comparing key performance indicators across dairy farms may provide insightful information to dairy producers. Differences in management philosophies, facilities, and locations of dairy farms may influence overall performance of dairy operations. An ongoing extension program aims to benchmark reproductive performance and transition cow health of dairy farms located in Kansas and adjacent states. In this report, we compiled data from 2013 to 2015 of herds enrolled in the program and divided the data in warm and cool seasons to evaluate the impact of heat stress on key performance indicators. Annual pregnancy risk and warm to cool ratio of pregnancy risk varied from 20.9 to 22.5% and 75 to 82%, respectively. Annual insemination risk varied from 63.6 to 66.4% and warm to cool ratio of insemination risk varied from 96 to 97%, which suggests that heat stress does not remarkably affect insemination risk. In contrast, conception risk is significantly affected by heat stress because conception risk in the warm season ranged from 26.7 to 29.6% and in the cool season from 34.5 to 35.4% from 2013 to 2015. Percentage of cows that were treated for mastitis within 21 d after calving was below 4% annually. Warm to cool ratio of percentage of cows treated for mastitis ranged from 139 to 170%, indicating that during summer, cows are at increased risk of being affected by early postpartum mastitis. Benchmarking key performance indicators may assist dairy producers to identify areas of opportunity for improvement

Assessing Training Methods to Educate Dairy Workers

Training employees is fundamental for dairy producers to achieve efficiency in order to increase profitability. Training videos offered online are becoming more common and recommended to train employees. The goals of this survey were to evaluate the comfort level of dairy employees in using computers and tablets, and preferred training delivery methods. A total of 71 employees from 6 dairies were interviewed. Interviews were conducted in the preferred language of the interviewee – English or Spanish. Of the respondents, 52 and 65.6% of employees consider computers and tablets easy to use, respectively. More than half of the employees reported that they do not use computers or tablets on a regular basis. The majority of employees (70%) would rather have a training session in a face-to-face format than a computer- or tablet-based format. This survey suggests that dairy employees may not be comfortable using computers in training sessions, which may limit the utility of some specific technologies to educate employees

Interactions of cationic formulations on human hair: Effects on cuticle texture and cortex porosity

During the daily care as cleansing, bleaching, ironing and others the hair fiber becomes damaged due to alterations in superficial charges, cuticle breakage and the protein loss from cuticle and cortex (1,2). Cationic formulations are used to treat damaged hair fiber. Cuticle and cortex properties change by the adsorption and diffusion of formulation ingredients (1,2). The adsorption of cationic surfactants containing quaternary ammonium on hair surface has been majority attributed to electrostatic interactions between the negatively charged cuticle after shampooing and the positive charge of these compounds (1). The uniformity of the adsorbed layer has direct influence on damaged hair texture (3,4). Recent advances in computational image analyses and very low angle illumination on light microscope allow us to develop a new approach of hair texture evaluation (5). On the other hand, the diffusion of ingredients into cortex has been attributed mainly to size, concentration and affinity between the molecule and hair. Cationic surfactants play an important role in the diffusion process due to the deposition and charge-charge interactions on hair surface (1). The aim of this study was to obtain quantitative data on hair cuticle texture and hair cortex porosity for healthy and damaged hair. The images of surface hair (texture) obtained by light microscope were categorized using by (GTSDM) grey-tone spatial dependence matrices. Bleached hair samples were treated with different conditioning formulations applied as leave on and rinse off processes. After bleaching treatment, the hair texture is significantly different from the control healthy hair. When a cationic formulation and rinsing off process were used, the bleached hair texture improvement by lowering energy beyond the measured to control healthy hair. Cationic formulation using leave on process does not allow the same results, however still improves the texture condition of bleached hair. The quantitative data and images from cortex porosity were analyzed using X-ray micro–computed tomography (micro-CT) that is a fast-growing method in scientific research applications that allows the obtaining of non-destructive imaging of morphological structures (6,7). The influence of cationic compounds on cortex porosity after treatments was observed. We used two types of leave on formulation on bleached hair, the first formula containing cationic ingredients and the second formula without cationic. The formulation without cationic showed a significant reduction of cortex porosity, about 70% compared to the bleached hair only. Meanwhile another formulation, did not show the same performance. The data obtained indicate that the conditioner formulation can improve hair texture and decrease cortex porosity. The charge-charge interaction allows the adsorption or diffusion of the formulation ingredients into the hair. References: 1_Schueller, R and Romanowski. Conditioning Agents for Hair and Skin. Cosmetic Science and Technology vol 21, 1999. 2_Johnson, D.H. Hair and Hair Care. Cosmetic Science and Technology vol 17, 1997. 3_ Aita, Y. and Nonomura, Y. J. Oleo Sci. 65, (6) 493-498, 2016. 4_La Torre, Carmem. J.Cosmet.Sci., 57, 37-56 (January/February), 2006. 5_ Scanavez, C and Arcuri, H. Proceedings of the 20th International Hair-Science Symposium, Dresden, Germany, September 2017. 6_Anton du Plessis et al. Laboratory x-ray micro-computed tomography: a user guideline for biological samples, GigaScience, 6 1–11, 2017. 7-Santini, M. Journal of Physics: Conference Series, 655, 2015

Case Study: Improving Heat Abatement Strategies for Lactating Dairy Cows in Southwest Kansas

Temperature loggers attached to intravaginal devices can be used to assess severity of heat stress in dairy cows. Vaginal temperature data collected using this method can be used to evaluate effectiveness of heat abatement systems. The goal for this study was to use vaginal temperature information to evaluate the impact of implementing new heat abatement strategies in order to minimize heat stress in lactating dairy cows. Vaginal temperature of cows from 2 dairies located in southwest Kansas were assessed during summers of 2014 and 2017. Dairy A improved the heat abatement systems in 2017, while Dairy B did not. Historical information of herd fertility was evaluated from 2012 to 2017 for both herds. In 2014, cows from Dairy A had greater vaginal temperature compared with Dairy B. The assessment conducted in 2017, after implementation of new heat abatement strategies, revealed that cows from Dairy A had comparable vaginal temperature to their counterparts from Dairy B. This indicates that the new cooling system minimized the effects of heat stress. Moreover, fertility of Dairy A in the summer of 2017 was improved compared with previous years. Herd fertility during the summer was better in Dairy B than Dairy A from 2012 to 2016. In contrast, Dairy B had poorer fertility than Dairy A in 2017. These data suggest that fertility of dairy herds may be positively impacted by reducing heat stress through improved cooling systems

Impact of heat stress on health, production, and reproductive performance of dairy cows

Doctor of PhilosophyDepartment of Animal Sciences and IndustryLuis G. MendoncaHeat stress poses major challenges to the dairy industry, disrupting the well-being and productivity of cows. Besides affecting lactating cows, exposure to heat stress during the dry period increases core body temperature (CBT) and alters hormonal profile and mammary gland development, ultimately affecting milk yield in the subsequent lactation. Reproductive performance is severely reduced in dairy cows exposed to heat stress. Even though it is well accepted that estrus expression is reduced during periods of heat stress, it is not clear whether herd-level indicators of estrus-detection efficiency, such as insemination risk, are impacted during periods of heat stress. This dissertation focused on exploring the use of CBT during the dry period as a predictor of postpartum health, production, and reproductive performance during the subsequent lactation. Furthermore, potential implications of heat stress and other seasonal stressors on insemination risk were evaluated. Study 1 investigated the relationships between CBT during the dry period and health, milk production, and reproduction during the subsequent lactation. Dry cows with increased CBT were more susceptible to health disorders and had reduced milk yield early in the subsequent lactation. No association was observed between CBT during the dry period and reproductive performance after parturition. Study 2 explored factors associated with CBT in dry dairy cows and focused on determining the ideal time of the day to assess CBT of heat-stressed dry cows. Core body temperature was increased in cows pregnant with twins and was associated negatively with gestation length. Furthermore, results indicated that 2215 h is the most appropriate time of the day to assess CBT of dry cows exposed to heat stress. Study 3 aimed to compare physiologic and metabolic characteristics of cooled cows classified as having high or low CBT during the dry period. In addition, this study investigated the association between CBT during the dry period and health, milk yield, and reproductive performance after parturition. Cows with high CBT during the dry period had distinct concentrations of pregnancy-associated glycoprotein and indicators of energy balance during the transition period and had reduced milk yield compared with low-CBT cows. Furthermore, CBT during the dry period was a useful predictor of postpartum health disorders. Reproductive performance, however, did not differ between cows that had high or low CBT during the dry period. Study 4 investigated temporal patterns of insemination risk in large dairy herds and explored associations between insemination risk and herd-level traits. Seasonal variation of insemination risk was minimal, with increased insemination risk observed during autumn. Greater values of insemination risk were observed in dry-lot herds, with low mortality of cows, and longer voluntary waiting period for primiparous cows. In summary, assessment of CBT in dry cows may be a useful tool to identify groups of cows more likely to present health disorders and impaired productive performance after parturition. In addition, insemination risk is not reduced during the summer, but it is severely affected by herd-level traits such as housing system, mortality of cows, and voluntary waiting period for primiparous cows

Association Between Reproduction and Postpartum Cow Health during Summer Months in Dairies Located in the Great Plains Region

Postpartum cow health has an impact on fertility of dairy cows, and impaired fertility in dairy herds ultimately influences profitability of dairy farms. During summer months, postpartum cow health and reproductive performance are affected in dairies located in the Great Plains region. The goal for this study was to evaluate farm-level associations between reproductive efficiency and postpartum cow health in dairy herds located in the Great Plains region. Data from June to August of 2010 to 2016 from 18 herds located in Colorado, Kansas, Oklahoma, Nebraska, and Texas were extracted. Overall pregnancy per AI was used as the measure of reproductive efficiency, and percentage of stillbirth cases, mastitis within 21 d after calving, and cows sold and cows dead within 60 d after calving were used to evaluate postpartum cow health and performance. Using the intercept and slopes from a logistic regression model, a transition cow index was created. Poor herd fertility, pregnancy per AI \u3c 30%, was associated with percentage of stillbirth events and postpartum mastitis cases. In 93% of the instances that herds had pregnancy per AI \u3c 30%, transition cow index was less than 0. This study demonstrates that fertility is associated with transition cow performance at the herd level during summer months in dairies located in the Great Plains region

Evaluation of Weather Information from On-Farm and Meteorological Stations to Assess Heat Stress in Dairy Cows in Southwest Kansas

Heat stress represents a challenge for the dairy industry. In order for producers to implement appropriate management practices, it is crucial for researchers to assess the extent of heat stress to which cows are exposed during the summer. Temperaturehumidity index (THI) may be used to determine the severity of heat stress that cows are exposed to during the summer. The objective of this study was to evaluate climate conditions by calculating THI using information from: 1) an official meteorological station, 2) loggers at the pen-level, and 3) loggers at the cow-level from a commercial dairy located in southwest Kansas. Temperature-humidity index at the cow-level was correlated with THI at the pen-level and THI from the nearest official meteorological station to the dairy. Despite the correlations, cow-level THI was 6.8 and 19.2 units greater than pen-level and station-level THI, respectively. Weather data obtained from farm-level measurements are more accurate than information collected from an official meteorological station to assess the intensity of heat stress conditions. Nonetheless, it is important to note that pen-level THI underestimates the index at the cow-level. This difference is likely to occur because of microclimates within the pen

Are My Dry Cows Heat-Stressed? A Novel Approach to Assess Heat Stress of Dry Cows in Commercial Dairy Herds

Heat stress during the dry period causes major economic losses to the dairy industry. However, limited research exists regarding responses of dry cows exposed to various temperature and relative humidity gradients. In addition, no validated methods are currently available to assess heat stress in dry cows. The goals of this study were to describe core body temperature (CBT) responses of dry cows according to a variety of temperature-humidity index (THI) values, and develop and validate a practical method to assess heat stress in dry cows in commercial dairy herds. This study was comprised of 2 parts. In the first part of the study, vaginal temperature of dry cows (n = 346) with 250 to 260 days of gestation from 5 herds was assessed for 4 to 7 consecutive days in 5-minute intervals. Within dairy and parity group, cows were classified as having high (HT) or low CBT (LT). By design, CBT was greater for HT compared with LT cows (102.3 ± 0.01 vs. 101.8 ± 0.01°F). Cows classified as having HT had shorter gestation length compared with their LT counterparts (272.5 ± 0.2 vs. 275.1 ± 0.2 days). The second part of the study consisted of evaluating and validating a practical assessment method of heat stress and investigating CBT threshold values. Vaginal temperature of 1,540 dry cows with 236 to 250 days of gestation from 3 commercial dairy herds was assessed a single time using a digital thermometer. Average CBT of HT cows at each THI (data from the first part of the study) was used as a threshold value to classify cows as heat-susceptible or heat-tolerant. Cows with higher or lower CBT than the threshold defined for a given THI were classified as heat-susceptible or tolerant, respectively. Cows classified as heat-susceptible had shorter gestation length (272.5 ± 0.2 vs. 275.0 ± 0.2 days) and were more likely to have twins (11.0 vs. 3.8%) than heat-tolerant cows. In conclusion, assessment of heat stress in dry cows based on defined CBT thresholds is a useful method to identify cows expected to have shorter gestation length and more likely to have twins

Effects of Two Commercial Supplemental Fat Products on Body Condition Score and Cow- and Herd-Level Milk Yield and Composition in a Commercial Dairy Herd in Kansas

Feeding fat supplements to lactating dairy cows is an effective strategy to increase energy density of rations and increase milk yield. However, it is not clear whether supplementing a specific fat supplement for the entire lactating herd provides better results than others in commercial dairy herds. The objective of this study was to compare the effects of fat supplementation with two commercial products on changes in body condition score (BCS) and cow- and herd-level milk production and composition in a large commercial dairy herd. The study was conducted in a herd milking approximately 1,500 Holstein cows. One of two treatments was assigned to the herd in a singlesubject crossover design with 4 periods. Treatments were inclusion of 0.24 lb/cow per day of a supplement rich in saturated fats (Propel; Propel Energy Plus) or 0.22 lb/cow per day of a supplement containing calcium salts of long-chain fatty acids (Control). Treatments were applied to all lactating cows during four consecutive weeks. Milk yield recorded during the last week of each period was used for statistical analyses. In addition, milk samples were collected in the last week of each period to determine test-day milk protein, fat, somatic cell count, and urea nitrogen concentrations. At the beginning and at the end of each experimental period, BCS was assessed from a subset of cows to evaluate BCS change. Herd-level milk fat, protein, and somatic cell count were recorded daily by the milk cooperative. Bulk tank milk fat and protein contents on the fourth week of fat supplementation were similar between Control and Propel treatments. Average milk yield during the fourth week of fat supplementation (yield recorded daily in the last week of the experimental period) was greater for Control than Propel supplementation (83.4 vs. 82.1 ± 1.7 lb/day). In the analyses that used test-day data, milk yield did not differ between Control and Propel treatments. Supplementation with Propel resulted in greater milk fat (4.50 vs. 4.29 ± 0.12%) and reduced milk protein content (3.12 vs. 3.14 ± 0.03%) compared with Control. In addition, milk urea nitrogen was reduced for Control vs. Propel cows (12.5 vs. 13.1 ± 0.04 mg/dL). Supplementation with Propel increased energy-corrected milk (93.9 vs. 91.7 ± 3.1 lb/ day) and fat-corrected milk (96.3 vs. 93.5 ± 3.3 lb/day) yields compared with Control supplementation. Proportion of cows that lost BCS during the fat supplementation periods did not differ between treatments; however, BCS change tended to be more pronounced during supplementation with Propel than Control treatment (-0.03 vs. 0.02 ± 0.04). In conclusion, fat supplementation using the Propel treatment resulted in greater milk fat content, energy-corrected milk, and fat-corrected milk compared with fat supplementation with Control. Our findings suggest that the type of market to which milk is sold should be considered in the choice of fat supplements

Gestation Length and Overall Performance in the Subsequent Lactation of Dairy Cows Conceiving to Holstein, Jersey, or Angus Semen: An Observational Study

Breeding strategies adopted by commercial dairy herds have evolved in recent years by incorporating the use of several breeds, including beef sires. Results of such strategies on offspring performance have been studied but reports on the effects on dam’s overall performance after calving are still lacking. The goal of this observational study was to investigate the associations between sire breed of previous conception, gestation length, and postpartum performance of dairy cows. Records from Holstein and crossbred cows from a Kansas commercial herd were extracted. Data pertaining to cows that conceived from Holstein, Jersey, or Angus sires and initiated second lactation or greater from June 2017 to May 2018 were used in this study. Gestation length was shorter for cows that conceived from Holstein (274.9 ± 0.6 days) compared with Angus sires (276.5 ± 0.6 days). Cows that conceived from Jersey sires had the longest gestation length (278.0 ± 0.4 days). For Holstein cows, milk yield in the first 60 days after calving was influenced by sire breed used on the previous lactation. Holstein cows that became pregnant with Holstein sires had the lowest milk yield compared with other permutations of dam and conceptus breeds. Interestingly, sire breed of previous conception did not influence milk yield in the subsequent lactation of crossbred cows. Cows that became pregnant with Angus sires had greatest incidence of postpartum disorders compared with cows conceiving from Jersey or Holstein sires (28.0, 11.5, and 9.4%, respectively). Nonethe­less, sire breed of previous conception did not affect probability of culling in the first 60 days after calving. This study presents evidence that breed of conceptus influences gestation length and milk yield of the dam in the subsequent lactation