PRE-WEANED CALF REARING OPTIONS FOR ORGANIC DAIRY SYSTEMS

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: OTHER GRANTS
• Reporting Frequency: Annual
• Accession No.: 1023509
• Grant No.: 2020-51300-32177
• Cumulative Award Amt.: $998,650.00
• Proposal No.: 2020-02116
• Project Start Date: Sep 1, 2020
• Project End Date: Aug 31, 2024
• Grant Year: 2020
• Program Code: [113.A]- Organic Agriculture Research & Extension Initiative

Recipient Organization
UNIV OF MINNESOTA
(N/A)
ST PAUL,MN 55108

Performing Department
CFANS West Central ROC Morris

Non Technical Summary
Ourmultidisciplinary team conducted advisory interviews and conducted research projects with organic dairy farmers, and we concluded that organic dairy producers are concerned about dairy calf rearing systems and the challenges with calf health in an organic production system to remain viable in the organic dairy industry. The present proposal addresses these challenges through research involving the University of Minnesota's West Central Research and Outreach Center's certified organic dairy and cooperating organic dairy farms in the region. The overarching goal of our project is to identify organic dairy calf rearing options that promote health and welfare in the organic livestock industry. We will develop methods to investigate the management feasibility of three alternative calf-rearing options: group housing in outdoor super hutches; pair housing of calves; and outdoor housing with the dam on pasture compared to traditional individual housing in outdoor hutches. We will also evaluate markers of calf health, behavior and welfare to ultimately provide recommendations on best calf rearing options for organic producers. Our stakeholder group of organic farmers helped identify and develop the objectives included in this proposal; and they will provide leadership for coordinated on-farm field research and sites for field days. The results of this project will be valuable to organic dairy producers, and will be disseminated to organic producers and industry representatives throughout the United States. Our research results will be shared with our larger stakeholder groups through field days, conferences, publications, and webinars.

Animal Health Component

100%

Research Effort Categories

Basic

(N/A)

Applied

100%

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
307	3499	1060	50%
315	3499	1060	50%

Knowledge Area
307 - Animal Management Systems; 315 - Animal Welfare/Well-Being and Protection;

Subject Of Investigation
3499 - Dairy cattle, general/other;

Field Of Science
1060 - Biology (whole systems);

Keywords

organic dairy

calf health and outreach

Goals / Objectives
The long-term goal of this project is to enhance organic dairy production by improving organic dairy calf health and welfare. This overarching goal will be achieved by identifying the best calf housing options that give rise to positive calf welfare by performing a controlled research trial and on-farm studies. Specifically, we will 1)measure and evaluate markers of animal welfare outcomes of health, behavior, and emotional state of calves reared by: 1) individual housing (control); 2) pair housing; 3) group housing; and 4) with dam on pasture, 2)conduct on-farm benchmarking of health measures for each rearing option, and 3)determine the management feasibility through focus groups for each rearing option.The results of this project will be valuable to organic dairy producers, and will be disseminated to organic dairy producers and industry representatives throughout the United States. We willprovide recommendations on best calf rearing options for dairy producers to implement based on welfare outcomes, health benchmarks, and management feasibility.

Project Methods
The goal of this project is to identify organic dairy calf rearing options that promote animal welfare. This goal will be achieved by completing project objectives that include: 1) measure and evaluate markers of animal welfare outcomes of health, behavior, and emotional state of calves, 2) conduct on-farm benchmarking of health measures for calf rearing, and 3) to determine the management feasibility through focus groups of calf rearing options. Data collected will be analyzed using models using the SAS Software (2019) for statistical analyses to obtain means and measurements of error. Models will be adjusted accordingly for each individual research study design. Pen and farm will be the experimental units for the study conducted at the WCROC and for the on-farm study, respectively. For data from calves housed together in pairs, the average of the 2 animals will be calculated, and this will be considered as a single observation. Because the data are means and the variance of a mean of n units is σ2/n, the number of calves per mean will be used as a weighting in the analysis (1 for individually housed calves, 2 for calves housed in pairs, 6 for calves housed in groups and dam-calf pairs). This makes the observations with heavier weight or higher precision more important than others, thus correcting for the imbalance of the design of individual versus group situations (Lensink et al. 2001). A repeated measures analysis will be performed to analyze measures taken more than 3 times on the same experimental unit (i.e. health scores, body weight, etc. for the experiment conducted at the WCROC). However, some measures may be aggregated into 1 measurement to simplify the analyses (i.e. health scores). For some measures (i.e. behavior and cortisol), data will be evaluated using non-parametric methods and logistic regression analysis. Categorical data obtained (i.e. focus groups, surveys, passive immunity success and failure) will be analyzed using a Chi Square test. Treatment means will be separated using multiple comparisons tests (e.g., Tukey or Bonferroni). Data analysis will be planned very carefully to consider all potential interactions and confounding effects. Seasonality and calf birth body weight and physiologic size could be a confounding factor in the analysis. These will all be adjusted for in the statistical analysis. To control for confounding in the analyses, we would either use Stratification and Multivariate methods. Stratification will allow us to fix the levels of confounders and make groups within which the confounder does not vary. Exposure-outcome association within each stratification of the confounder would be created, and therefore, the confounder cannot confound because it does not vary across the exposure-outcome. Stratified analysis works best in the way that there are not a lot of strata and if only 1 or 2 confounders must be controlled. Multivariate methods would be the more accepted form on statistical analysis if there are many potential confounders. Multivariate models can handle large numbers of covariates (and confounders) simultaneously. One method would be to use logistic regression to produce results that can be interpreted as an odds ratio. Logistic regression can control for numerous confounders. Odds ratios can be adjusted other covariates (including confounders). Another statistical analysis to consider is the Analysis of Covariance (ANCOVA) to control for potential confounding variables.For least squares means from ANOVA or ANCOVA, we can adjust the means for the observed marginal distributions of the variable rather than using equal coefficients across classification effects to determine the correct means adjusted for confounding and interaction effects.?

Progress 09/01/20 to 08/31/24

Outputs
Target Audience:We have reached organic dairy farmers across the United States. Information provide to farmers has been disseminated in print and and audio formats. We have also provided information from the project to veterinarians, organic dairy industry representatives across the United States on the calf housing proejct. We have also trained1 research scientistand 1 graduate student in experimental design and collection of research data. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The project has trained organic dairy producers on the housing systems for pre-weaned dairy calves for organic production. Many extension educators and organic industry representatives were informed on housing systems and raising dairy calves at the Minnesota Organic Conference. We have also trained a graduate student in proper experiemental design, data collection, and analysis of data. Graduate stduents from Minnesota presented research on housing systems for organic produciton at the American Dairy Science Association meeting in June 2024 in West Palm Beach Florida. How have the results been disseminated to communities of interest?Over 1000 people have attended presentations related to the objective research in the project. Results were disseminated to academic and audiences through peer-reviewed publications and abstracts presented at conferences. Presentations were also given that included farmers that have used our research results at grazing and organic conferences. We also have small focus group meeting with organic dairy farmers on a monthly basis where we showcased these results from the project. Furthermore, the information was disseminated on The Moos Room podcast. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Calf-rearing practices in pasture-based and organic dairy farms in the Midwest United States.There is an increased societal demand for improved conditions in calfrearing management. Calf-rearing practices in organic and pasture-based dairy farms in the Midwest can be very diverse but are not well documented. This ongoing study aims to describe calf-management practices of organic and pasture-based dairy farms in the Midwest. Pasture-based (at least 120 grazing days per year) dairy farmers in the Midwest received an invitation (emails, social media, farming events, and phone calls) to participate in an in-person survey. Thirteen (certified organic n = 7; certified organic and grass-fed n = 4; transitioning to organic certification n = 1; pasture-based noncertified n = 1) farmers agreed to the in-person interviews, performed with a standard questionnaire with open-ended questions. Due to the diversity of the systems and the low number of farms, only descriptive data analyses are shown. The median herd size was 75.5 cows (34-321 cows). Most farms (67%) separated cows and calves 1 to 48 h after birth. A smaller portion of farms (33%) allowed more than 3 d of full or partial cow-calf contact with the dam or foster cows and reported reduced labor and improved animal health from this practice. Calves separated from cows received 2.4 L to 16 L of milk daily, with 66% of farms feeding 6 L of milk or less. Milk was offered using one or more of the following methods: buckets with nipples (11%), bottles (33%), buckets without nipples (33%), or mob feeders (66%). Step-down weaning strategies were used on 92% of farms. Calves housed in groups (75%) were the most predominant housing type and were used in combination or as an alternative to individual, cow-calf, or pair housing. Only 36% of organic farmers agreed they could treat diseases in calves using organic-approved options, and 82% reported pneumonia as the most challenging disease to cure. Also, 33% of farms used a vaccination program. This survey demonstrates a high diversity of practices allowing dairy calves to have social contact.

Publications

• Type: Conference Papers and Presentations Status: Accepted Year Published: 2024 Citation: Organic Milk Production in the USA. SUSTAG 8000, November 9, 2023. University of Minnesota, St. Paul
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2024 Citation: Improving the Health of Organic Dairy Cows & Heifers. Minnesota Organic Conference, January 12, 2024. St. Cloud, Minnesota
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2024 Citation: Organic Milk Production in the USA. SDSU Dairy Science Class, March 1, 2024. South Dakota State University, Brookings, South Dakota Status: Accepted Year Published: 2024 Citation: Gon�alves da Costa, B., B. Heins, and M. Endres. 2024. Calf-rearing?practices?in?pasture-based?and?organic?dairy?farms?in?the?Midwest?United?States. . Dairy Sci. Vol. 107, Suppl. 1 (Abstract #2479) p.350
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2024 Citation: Pre-Weaned Calf-Rearing Options for Dairy Producer. OREI-PD Meeting, Orlando, FL, April 2024
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2024 Citation: Organic Milk Production in the USA. SDSU Dairy Science Class, March 1, 2024. South Dakota State University, Brookings, South Dakota

Progress 09/01/22 to 08/31/23

Outputs
Target Audience:We have reached organic dairy farmers across the United States, and around the world. Information provide to farmers has been disseminated in many forums.We have also provided information from the project to veterinarians, organic dairy industry representatives across the United States on the calf housing proejct.Afield day was offered for organic dairy producers, extension educators, and organic industry personnel during August 2023. We have also trained 3 undergraduate , 1 research scientist, and 1 graduate student in experimental design and collection of research data. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The project has trained organic dairy producers on the housing systems for pre-weaned dairy calves for organic production. Many extension educators and organic industry representatives were informed on housing systems and raising dairy calves on cows at the University of Minnesota organic dairy field day in August 2023. At the field day farmers were interviewed and feedback was provided to researchers about all aspects of the project. A video was produced on farmers providing feedback on the calf housing project and how the project has impacted their operations. The video was shown at an all Extension conference in Minnesota. We have trained 3 undergraduate students on how to conduct research and outreach with housing systems of calves. We have also trained a graduate student in proper experiemental design, data collection, and analysis of data, along with microbiome data anlaysis. Graduate stduents from Minnesota presented research on housing systems for organic produciton at the American Dairy Science Association meeting in June 2023 in Ottawa, Canada. Results from the study were also presented in poster format at the February 2023 MarbleseedOrganic Conference in LaCrosse, WI, and the 2023 Dairy Welfare Council Meeting in May 2023. How have the results been disseminated to communities of interest?We had an in-person organic dairy day at the University of Minnesota West Central Research and Outreach Center in August 2023 to provide farmers and other industry personnel tools that they can take back to their farm when implementing alternative calf housing systems. During the last year, over 150 people have attended the field days at the WCROC. Over 500 people have attended presentations related to the objective research in the project. Results were disseminated to academic and audiences through peer-reviewed publications and abstracts presented at conferences. Presentations were also given that included farmers that have used our research results at grazing and organic conferences. Videos were also produced to elicit feedback from organic dairy farmers on the progress of the project and how the project has impacted their thoughts and dairy operations. What do you plan to do during the next reporting period to accomplish the goals?The investigators on the project continue to review objectives and accomplishments of the project. We continue to collect data for the rearing project, Abstracts and peer-reviewed publications will be drafted. We are collecting data on organic dairy farms to benchmark calf growth. Also, a graduate student will complete her PhD with the project and write 3 peer reviewed publications. Two other peer reviewed publications will be authored by the project investiagators.

Impacts
What was accomplished under these goals? Growth and health costs of dairy calves raised in individual, pair, or group housing compared to dairy calves raised on cows. The purpose of this study was to investigate growth at weaning and incidence of treatments for scours, respiratory, and other health issues of pre-weaned dairy calves raised in individual (I), pair (P), group (G), or dam- raised (D) housing systems. The study was conducted at the University of Minnesota West Central Research and Outreach Center, Morris, MN. Three-hundred forty-five Holstein and crossbred calves were assigned to housing treatments during 3 fall calving seasons and 2 spring calving seasons from September 2020 to November 2022. The I, P, and G raised calves were enrolled at 3 d and fed 10 L of whole milk per d. Calves raised by their dam were isolated together for 3 d and introduced to a larger cow-calf group where they nursed ad libitum. All calves were weaned at 63 d. Independent variables were the fixed effects of breed group birthweight, season of calving, and treatment group. Pen within season was a random effect. Hip height for I, P, G, and D calves was not different (P > 0.05). The D calves had similar heart girth to G calves, but larger (P < 0.05) heart girth (114.1 cm vs. 111.1 and 110.6, respectively) to I and P calves. The D calves had higher (P < 0.05) average daily gain (1.15 kg/d vs. 0.98, 0.96, and 0.99 kg/d, respectively), higher (P < 0.05) weaning weights (112.1 kg vs. 99.7, 99.2, and 102.8 kg, respectively), and higher (P < 0.05) total gain (74.1 kg vs. 61.9, 60.9, and 64.3 kg/d, respectively) than I, P, and G calves. The D calves had more (P < 0.05) calves triple their birthweight (52.9%) than I, P, and G calves (12.8, 14.4, and 15.5%, respectively). The G calves had higher (P < 0.05) health costs ($5.11/calf) than I, P, and D calves ($1.23, $1.16, and $1.54, respectively). The G calves had a higher (P < 0.05) incidence for treatment of scours (20.2 vs 7.0 and 9.4%, respectively) than I and D calves. The G calves had a higher (P < 0.05) incidence for treatment of respiratory problems than I, P, and D calves (15.5 vs 3.5, 1.1, and 3.5%, respectively). Results from this study indicate there may be growth advantages to raising calves with their dams during the pre-weaning period. Seasonality of colostrum BRIX values and total serum protein of newborn dairy female calves in a temperate climate. The aim of this study was to investigate if total serum protein (TSP) of newborn dairy female calves varied between Fall and Spring calving seasons. The experiment was conducted at the University of Minnesota West Central Research Outreach Center (WCROC), Morris, Minnesota. The WCROC has two calving seasons per year: Fall (September to December) and Spring (March toJune). In this study were enrolled 263 female calves from three different breeds Grazecross (n=62), ProCross (n=130) and Holstein (n=71) born during Fall 2020(n=69), Spring 2021 (n=44), Fall 2021 (n=57), Spring 2022 (n=30) and Fall 2022(n=63). Calves were separated from dams during the first day of life and fed 4 liters of colostrum from their dams. Colostrum samples were collected during the first milking after calving and a BRIX value was obtained using a MISCO digital refractometer. Blood samples were collected 24 to 48 hours after birth, centrifuged and (TSP) were obtained using a MISCO digital refractometer. For statistical analysis, the fixed effects included season (Fall or Spring) and BRIX and breed was a random effect for . Year was also included as a fixed effects for BRIX anlaysis. Calves born during Fall (5.8 g/dl± 1.2) had higher (P <0.01) TSP than calves born during Spring (5.4 g/dl ± 1.0). Breed and BRIX values did not affect TSP. Colostrum brix values did not vary across Fall and Spring seasons (P=0.78). The BRIX value from Fall 2021 was lower than all other seasons (P <0.05), except for Spring 2021 (P=0.14).The results suggest that seasonality may influence IgG absorption. Milking parlor behavior, body measurements, and body condition scores of first lactation cows raised in individual, pair, or group housing compared to dam-reared housing. The objective of this study was to determine milking parlor behavior, body measurements, and body condition scores of first lactation cows raised in individual (I), pair (P), group (G), or dam- raised (D) housing systems during the pre-weaning period. The study was conducted at the University of Minnesota West Central Research and Outreach Center, Morris, MN. Seventy-nine Holstein and crossbred heifer calves were assigned to housing treatments by birth order and were born from September to December 2020. The I, P, and G raised calves were placed in a housing system at 3 d and were fed 10 L of milk per d. Calves raised by their dam were isolated with the dam for 3 d and introduced to a larger group where they suckled ad libitum. All calves were weaned at 63 d. First lactation cows for the current study calved from September to November 2022. Behavior measurements were from the first 8 milkings after calving. Independent variables were the fixed effects of breed, treatment, milker, and cow and date of measurement were repeated effects. Dam-reared cows had 2.3 ± 0.3 times greater (P < 0.01) odds of being restless, very restless, or hostile during milking than I, P, and G cows. Furthermore, dam-reared cows had 2.3 ± 0.3 times greater (P < 0.01) odds of stomping, 4.3 ± 0.4 times greater (P < 0.01) odds of kicking off the milking unit, and 2.3 ± 0.3 times greater (P < 0.05) odds of kicking than I, P, and G raised cows. The G cows had larger (P < 0.05) heart girth than D cows (198.4 cm vs. 189.2 cm), but similar heart girth to I and P cows. The I, P, and G cows had larger (P < 0.05) rear udder width (5.2 cm, 4.8 cm, and 5.4 cm, respectively) than D cows (4.2 cm). Hip height, body length, pin width, thurl width, rear udder height, body condition score at calving, and body condition score 4 weeks post-calving were not different (P > 0.05) for I, P, G, and D cows. Results from this study indicate there may be behavioral advantages to raising calves individually, in pairs, or in groups versus raising them with their dam during the pre-weaning period. Social housing: Impacts on health scores and gut microbiome of dairy calves. The aim of this study was to investigate the effects of social housing on the health scores of pre-weaning dairy calves and changes in the gut microbiome during weaning. A total of 343 Holstein (n = 79), ProCross, (n = 169), and GrazeCross (n = 97) calves were evaluated from fall 2020 to fall 2022. At 3 d of age, calves were divided into 4 housing groups: individually housed (n = 87), pair-housed (n = 86), group-housed (6 calves per pen; n = 84), and dam-reared (6 dam-calf pairs per paddock; n = 69) until weaning at 63 d of age. Before weaning there were no differences in microbiome diversity between treatments (P > 0.05). After weaning, individually housed calves had the tendency to have lower richness (Kruskal-Wallis P = 0.04955; W = 0.08). The microbiome of dam-reared and group-housed calves showed enrichment of gut bacteria such as lactobacilli and bifidobacteria, before and after weaning. Individual housing did not appear to have specific stimulating roles in the calf gut microbiomes. Our results suggest that social housing might affect fecal scores, while simultaneously stimulating the abundance of potentially beneficial bacteria in the gut.

Publications

• Type: Other Status: Accepted Year Published: 2023 Citation: UMN Extension Moos Room Podcast - June 26, 2023 Episode 176 - Heat stress in dairy calves with Bethany Dado-Senn
• Type: Other Status: Accepted Year Published: 2023 Citation: UMN Extension Moos Room Podcast -Mar 20, 2023 Episode 162 - UMN WCROC Dairy research update with Dr. Bradley J Heins
• Type: Other Status: Accepted Year Published: 2022 Citation: UMN Extension's The Moos Room - Nov 21, 2022 Episode 145 - How to identify sick calves -
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2023 Citation: Pre-Weaned Calf Rearing Options for Organic Dairy Farms OREI-PD Meeting, Washington DC, April 2023
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2023 Citation: Putting Organic Dairy Research to Work - Minnesota Organic Conference, January 6, 2023, St. Cloud, MN
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2022 Citation: Pre-Weaned Calf-Rearing Options for Dairy Producers, Minnesota Dairy Inititative Dairy Producer Workshop, Pipestone, MN, December 1, 2022
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2023 Citation: B. Gon�alves da Costa, K. Sharpe Moser, M. Endres, and B. Heins.Seasonality of colostrum Brix values and total serum protein of newborn dairy female calves in a temperate climate. J. Dairy Sci. Vol. 106, Suppl. 1 Abstract 2410, p 82.
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2023 Citation: B. Gon�alves da Costa, A. GOmez, K. Sharpe Moser, M. Endres, and B. Heins.Social housing: Impacts on health scores and gut microbiome of dairy calves. J. Dairy Sci. Vol. 106, Suppl. 1 Abstract 2411, p 82.
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2023 Citation: K. Sharpe and B. Heins. Milking parlor behavior, body measurements, and body condition scores of first-lactation cows raised in individual, pair, or group housing compared to dam-reared housing. J. Dairy Sci. Vol. 106, Suppl. 1 Abstract 2497, p 114.
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2023 Citation: K. Sharpe Moser, B. Gon�alves da Costa, M. Endres, and B. Heins.Evaluation of growth and health costs of dairy calves raised in individual, pair, or group housing compared to dairy calves raised with dams. J. Dairy Sci. Vol. 106, Suppl. 1 Abstract 2736, p 198.
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2023 Citation: Student Research Presentation: Dairy calves raised individually, in pairs, in groups, or with their dams by Bianca Costa, University of Minnesota. 2023 Dairy Cattle Welfare Symposium, Fort Worth, Texas, May, 2023

Progress 09/01/21 to 08/31/22

Outputs
Target Audience:We have reached organic dairy farmers across the Midwest and all of the United States. We have also provided information from the project to veterinarians, organic dairy industry representatives across the United States on the disbudding project. A field day was offered for organic dairy producers, extension educators, and organic industry personnel during August 2022. We have also trained 5 undergraduate , 1 research scientist, and 2graduate student in experimental design and collection of research data. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The project has trained organic dairy producers on the housing systems for pre-weaned dairy calves for organic production. Many extension educators and organic industry representatives were informed on housing systems and raising dairy calves on cows at the University of Minnesota organic dairy field day in August 2022. We have trained 5 undergraduate students on how to conduct research and outreach with housing systems of calves. We have also trained a graduate student in proper experiemental design, data collection, and analysis of data. Graduate stduents from Minnesota presented research on housing systems for organic produciton at the American Dairy Science Association meeting in June 2022 in Kansas City, Missouri. Results from the study were also presented in poster format at the February 2022 MOSES Organic Conference in LaCrosse, WI. How have the results been disseminated to communities of interest?We had an in-person organic dairy day at the University of Minnesota West Central Research and Outreach Center in August 2022 to provide farmers and other industry personnel tools that they can take back to their farm when implementing alternative calf housing systems. During the last year, over 250 people have attended the field days at the WCROC. Over 500 people have attended presentations related to the objective research in the project. Results were disseminated to academic and audiences through peer-reviewed publications and abstracts presented at conferences. Presentations were also given that included farmers that have used our research results at grazing and organic conferences. What do you plan to do during the next reporting period to accomplish the goals?The investigators on the project continue to review objectives and accomplishments of the project. We continue to collect data for the rearing project, and we begin initial analysis of growth and behavioral data. Abstracts and peer-reviewed publications will be drafted. We will also collect data on organic dairy farms to benchmark calf growth.

Impacts
What was accomplished under these goals? Growth and health costs of dairy calves raised in individual, pair, or group housing compared with dairy calves raised on cows. The objective of this study was to determine growth, health treatment costs, and incidence of treatments for scours, respiratory, and other health issues of dairy calves raised in individual (I), pair (P), group (G), or dam-raised (D) housing systems. The study was conducted at the University of Minnesota West Central Research and Outreach Center, Morris, MN, dairy. Two hundred 39 Holstein and crossbred calves were randomly assigned to housing treatments by birth order during 3 calving seasons from September to December 2020, March to May 2021, and September to November 2021. The I, P, and G calves were introduced to a housing system at 3 d and were fed 10 L of milk per d. Dam-raised calves isolated with the dam for 3 d after birth. After 3 d, the pair was introduced to a larger group where calves suckled ad libitum. All calves were weaned at 63 d. Data were analyzed using PROC MIXED and FREQ of SAS. Independent variables were the fixed effects of breed, pen, birthweight, season, and treatment, and pen within season was a random effect. Hip height was not different for I, P, G, and D calves. The D calves had higher weaning weight (113.9 kg vs. 99.3, 101.4, and 102.9 kg, respectively), larger heart girth (115.2 cm vs. 111, 111.8, and 112.9 cm, respectively), higher (P < 0.05) average daily gain (1.15 kg/d vs. 0.98, 0.98, and 0.99 kg/d, respectively), and higher total gain (75.5 kg vs. 62.1, 62.0, and 64 kg/d, respectively) than I, P, and G calves. More D calves tripled their birthweight (56.5%) than I, P, and G calves (10.7, 9.3, and 18.3%, respectively). The G calves had higher health costs ($3.34/calf) than I, P, and D calves ($1.37, $0.27, and $2.20, respectively). Treatments for respiratory and other issues were not different for I, P, G, and D calves. The G calves had greater (P < 0.05) incidence rate for treatment of scours (18.3%) than I, P, and D calves (3.57, 1.85, and 10.14, respectively). The results from this study indicate growth advantages to raising dairy calves with their dams during the preweaning phase. Health assessment of calves raised in alternative rearing systems. The objectives of this study were to investigate the effect of maternal contact on immunoglobulin absorption in the first 24 h of life and the occurrence of diarrhea and respiratory disease in dairy calves raised in alternative systems. Two hundred 41 Holstein (n = 61), ProCross, (n = 118), and GrazeCross (n = 61) calves were evaluated from Fall 2020 to Fall 2021. Analysis of passive transfer of immunoglobulins using total serum protein (TSP) was from a MISCO digital refractometer in 2 groups of calves: 1) separated from the dam (n = 170) and bottle-fed 4 L of colostrum in the first 12 h of life, and 2) dam-reared (n = 69) where calves suckled colostrum naturally. At 3 d of age, calves were divided into 4 housing groups: individually housed (n = 56), pair-housed (n = 54), group-housed (6 calves per pen; n = 60), and dam-reared (6 dam-calf pairs per paddock; n = 69). Dam-reared calves suckled milk naturally, while calves from all other treatments received 10L of milk per day until weaning at 63 d of age. Health scores were collected weekly using the Wisconsin Calf Health Scoring Chart until weaning. Statistical analyses for TSP were performed using PROC MIXED of SAS, and fixed effects were season, breed, and housing group. For health scores, analyses included PROC FREQ and PROC GLIMMIX of SAS with housing type, week, calf, breed, and season as fixed effects. There were no significant breed effects on the treatments. The TSP values were higher in dam-reared calves (TPR: 6.67 ± 0.32) than in separated calves (TPR: 6.16 ± 0.31). In total, respiratory disease was identified in 1.16% of observations, where 0.61% were from dam-reared calves, 0.29% from pair-housed, 0.20% from grouphoused, and 0.06% from individually housed calves. Scours occurred in 4.44% of the observations and was higher in dam-reared calves (6.9 ± 1.01%) than group (4.1 ± 0.75%), pair (1.1 ± 0.35%), and individually (0.5 ± 0.23%) housed calves, but similar in individually and pair-housed calves. The results suggest that dam-reared calves had higher absorption of immunoglobulins and that all rearing systems had a low occurrence of respiratory disease; however, scours were diagnosed more often in dam-reared calves. Lying behavior of dairy calves in alternative rearing systems. The objective of this study was to compare the lying behavior of dairy calves housed in alternative rearing systems before and during weaning. One hundred fifty-nine Holstein, ProCross (Montbéliarde, Viking Red, and Holstein,) and GrazeCross (Normande, Jersey, and Viking Red) calves were evaluated during Fall 2020 and spring 2021. At 3 d of age, calves were fit with IceTag (IceRobotics, Scotland) sensors on the right hind leg and divided into 4 housing groups: individually housed (n = 36), pair housed (n = 34), group-housed (6 calves per pen; n = 40), and dam-reared (6 cow-calf pairs per paddock; n = 49). Lying time and number of lying bouts were recorded daily until 3 d after weaning (d 63). Statistical analysis of lying time and lying bouts were with PROC MIXED of SAS with housing group, breed, and season as fixed effects. Random and repeated effects of calf and date were included in the model. Before weaning and across breeds, dam-reared calves (16.24 ± 0.17 h/d) spent fewer hours lying (P < 0.0001) compared with individually raised (17.91 ± 0.19), pair-housed (17.37 ± 0.19), and group-housed (17.24 ± 0.18) calves. Individually housed calves had more lying hours (P < 0.05) than all other housing systems. Group and pair-housed calves had similar lying times (P = 0.57). During weaning, group-housed (15.11 ± 0.33) had more lying hours per day (P < 0.05) compared with dam-reared calves (13.84 ± 0.28) and individual calves (14.22 ± 0.19). Pair-housed (14.51 ± 0.4) did not differ from any other housing group. There was no difference in the number of lying bouts before weaning; however, after weaning, dam-reared calves (24.17 ± 0.73) had a higher number of lying bouts than group calves (21.6 ± 0.8), but no differences between other housing systems were observed. The results suggest that pre-weaned calves individually housed spent more time resting, while dam-reared calves spent more time performing other activities. During weaning, group-housed calves spent more time resting than dam-reared and individually housed calves.

Publications

• Type: Other Status: Published Year Published: 2022 Citation: Heins, Brad. 2022. Organic Dairy Research News. University of Minnesota. July 2022. 8 pages
• Type: Other Status: Published Year Published: 2022 Citation: Nov 29, 2021 Episode 94 - Paired and group housing for dairy calves - UMN Extension's The Moos Room
• Type: Other Status: Published Year Published: 2022 Citation: Nov 22, 2021. Episode 93 - Brad's ADSA Discover Conference report - Calf housing, colostrum, lung ultrasound, and more - UMN Extension's The Moos Room
• Type: Other Status: Published Year Published: 2022 Citation: Nov 1, 2021 Episode 90 - Feeding dairy calves in the winter - UMN Extension's The Moos Room
• Type: Conference Papers and Presentations Status: Published Year Published: 2022 Citation: Costa, B., K. Sharpe, M. Endres, B. Heins. 2022. Health assessment of calves raised in alternative rearing systems. J. Dairy Sci. Vol. 105, Suppl. 1 Page 15. Abstr. 1037
• Type: Conference Papers and Presentations Status: Published Year Published: 2022 Citation: K. Sharpe, Costa, B., , M. Endres, B. Heins. 2022.Growth and health costs of dairy calves raised in individual, pair, or group housing compared with dairy calves raised on cows. J. Dairy Sci. Vol. 105, Suppl. 1 Page 23. Abstr. 1061
• Type: Conference Papers and Presentations Status: Published Year Published: 2022 Citation: Costa, B., K. Sharpe, M. Endres, B. Heins. 2022. Lying behavior of dairy calves in alternative rearing systems. J. Dairy Sci. Vol. 105, Suppl. 1 Page 47. Abstr. 1192
• Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Costa, B., K. Sharpe, M. Endres, B. Heins. 2021. Passive transfer of immunoglobulins and average daily gain of calves in alternative housing systems. 41st ADSA Discover Conference. October 25-28, 2021, Itasca, IL.
• Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: B. Heins and K. Sharpe. 2021. Rearing of Dairy Calves with Cows  A Pilot Study 41st ADSA Discover Conference. October 25-28, 2021, Itasca, IL.
• Type: Conference Papers and Presentations Status: Published Year Published: 2022 Citation: Costa, B., K. Sharpe, M. Endres, B. Heins. 2022. Lying time and growth of pre-weaned dairy calves in alternative rearing system. The 14th North American Regional Meeting of ISAE, University of California - Davis, ?April 29 & 30, 2022
• Type: Conference Papers and Presentations Status: Published Year Published: 2022 Citation: B. Heins and K. Sharpe. 2022. Alternative Dairy Management: NurseCows, Milk Once a Day, and More. 2022 Grassworks Conference, Wisconsin Dells, WI, Jan 20, 2022

Progress 09/01/20 to 08/31/21

Outputs
Target Audience:We have reached organic dairy farmers across Minnesota. We have also provided information from the project to organic dairy industry representatives, and other faculty at universities across the United States on the calf rearing project. A field day was offered for organic dairy producers, extension educators, and organic industry personnel. We have also trained 3 undergraduates and a graduate student in experimental design and collection ofm research data. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?The project has trained organic dairy producers on the housing systems fororganic dairy calves. Extension educators and organic industry representatives were informed on pre-weaned dairy calf rearing practices at the University of Minnesota organic dairy field day. We have trained 3 undergraduate students on how to conduct research and outreach. We have also trained 1 graduate studentin proper experimental design, data collection, and analysis of data. Faculty from Minnesota presented research on rearing of organic dairy calvesat the 2021 Virtual American Dairy Science Association meeting. How have the results been disseminated to communities of interest?We continue to offer an organic dairy day at the University of Minnesota West Central Research and Outreach Center to provide farmers and other industry personnel tools that they can take back to their farm and make changes. During the last year, over 50 people have attended the field days at the WCROC. Over 100 people have attended presentations related to the objective research in the project. Results were disseminated to academic audiences through peer-reviewed publications and abstracts presented at conferences. What do you plan to do during the next reporting period to accomplish the goals?The investigators on the project continue to review objectives and accomplishments of the project. We continue to collect data for the rearing project, and we begin initial analysis of growth and behavioral data. Abstracts and peer-reviewed publications will be drafted. We will also collectdata on50 organic dairy farms to benchmark calf growth.

Impacts
What was accomplished under these goals? Rearing of Organic Dairy Calves with Cows. The objective of this study was to determine growth and health of organic dairy calves raised on cows compared to calves fed in individual pens or calves raised on an automated calf feeder. The study was conducted at the University of Minnesota West Central Research and Outreach Center, Morris, MN, organic dairy. Forty-five Holstein and crossbred calves were assigned to treatment groups by birth order during one calving seasonfrom March to May 2020. Calves raised on cows (n = 14) were housed in a compost bedded pack barn and on pasture, individual calves (n = 16) were housed in single Calf-Tel hutch (Hampel Corp., Germantown, WI), and group calves (n = 15) were housed in an indoor-outdoor barn with a Holm & Laue HL100 Calf Feeder (Holm & Laue GmbH & Co KG, Westerronfeld, Germany). Calves raised on cows were allowed to bond with the dam for 3 days before being grouped with other calves and cows. Individual and group calves were introduced to hutch and feeder on day 4 and were fed 8 L/d. All calves were weaned at 90 d, and were weighed weekly and scored for health and behavioral measurements. Data were analyzed using PROC MIXED of SAS. Independent variables for analyses were the fixed effects of birthweight as a covariate, treatment group, along with calf within pen as a random effect. At weaning, calves raised on cows had higher (P < 0.05) weaning weight (137.6 kg vs. 120.0 kg vs. 128.4 kg, respectively) and average daily gain (1.12 kg/d vs. 0.93 kg/d vs. 1.01 kg/d, respectively) compared with individual calves and automated feeder calves. The individual-fed calves and calves from the automated feeder were not different (P > 0.05) for average daily gain. Average daily gain from birth to120 d of age, was not different (P > 0.05) for all treatment groups. The automated feeder calves had higher (P < 0.05) fecal scores (0.18) compared with calves raised on cows (0.04) and individual calves (0.03). The calves raised on cows had higher (P < 0.05) hygiene scores which indicated calves had dirtier bellies and sides than other treatment groups. The results from this study indicate that there may be advantages to feeding organic dairy calves on cows during the pre-weaning period. In this study, we investigate if dam-calf separation after birth affects the absorption of immunoglobulins in the first 24 hour of life. Additionally, average daily gain (ADG) was evaluated for calves from alternative preweaning calf-rearing housing during the first 9 wk of life. One-hundred sixty-four Holstein (40.8 kg birth weight), ProCross (Montbéliarde, Viking Red, and Holstein,39 kg birth weight) and GrazeCross(Normande, Jersey, and Viking Red,36.2 kg birth weight) calves were evaluated during Fall 2020 and Spring 2021. At 3 days of age, calves were divided into four housing groups: individually housed (n=36), pair housed (n=34),group-housed (6 calves per pen; n=40), and dam-reared (6 dam-calf pairs per paddock; n=49). Body weights at birth and at 9 wk of age were recorded. Statistical analyses were with PROC MIXED of SAS 9.4, and fixed effects were season, breed, and housing group. Across breeds, dam reared calves (1.21 kg/d ± 0.25) had higher (P < 0.05) ADG compared with individually raised (0.98 kg/d ± 0.13), pair-housed (0.96 kg/d ± 0.14) and group-housed (1.04 kg/d ± 0.17 ) calves. There was no difference (P > 0.05) in ADG among individual, pair and group-housed calves. Brix (9.45 ± 1.65 for dam-raised calves and 8.76 g/dl± 1.3 for all other calves) and serum total protein (6.2 ± 1.3 for dam-raised calves and 5.6 ± 1.09 for all other calves) was greater for dam-raised calves compared with calves in the other treatment groups. The results suggest that dam-reared calves have higher absorption of immunoglobulins and ADG than calves reared individually, in pairs, or groups.

Publications

• Type: Other Status: Published Year Published: 2021 Citation: Heins, Brad. 2021. Organic Dairy Research News. University of Minnesota. June 2021. 8 pages
• Type: Other Status: Published Year Published: 2020 Citation: Heins, Brad. 2020. Rearing of Dairy Calves with Cows. Dairy Star. November 14, 2020
• Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Heins, B. J. and K.T Sharpe. 2021. Rearing of organic dairy calves with cows. J. Dairy Sci. Vol. 104, Suppl. 1, p. 177
• Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Heins, B. J., M.I. Endres, and K.T. Sharpe. 2021. Preweaned calf rearing options for dairy producers. J. Dairy Sci. Vol. 104, Suppl. 1, p. 351
• Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Brad Heins. Rearing of Organic Dairy Calves with Cows. 2021 MOSES Organic Conference Online Seminar. February 26, 2021
• Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Pre-weaned calf rearing options for dairy producers. University of Minnesota Extension Winter Dairy Workshop Online. March 26, 2021
• Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Pre-weaned calf rearing options for dairy producers. Minnesota DHIA Regional Meeting Online February 24, 2021