Views of Western Canadian dairy producers on calf rearing: An interview-based study

Calf rearing practices differ among farms, including feeding and weaning methods. These differences may relate to how dairy producers view these practices and evaluate their own success. The aim of this study was to investigate perspectives of dairy producers on calf rearing, focusing on calf weaning and how they characterized weaning success. We interviewed dairy producers from 16 farms in Western Canada in the following provinces: British Columbia (n = 12), Manitoba (n = 2), and Alberta (n = 2). Participants were asked to describe their heifer calf weaning and rearing practices, and what they viewed as successes and challenges in weaning and rearing calves. Interviews were recorded, transcribed, and subjected to qualitative analysis from which we identified the following 4 major themes: (1) reliance on calf-based measures (e.g., health, growth, and behavior), (2) management factors and personal experiences (e.g., ease, consistency, and habit), (3) environmental factors (e.g., facilities and equipment), and (4) external support (e.g., advice and educational opportunities). These results provided insight into how dairy producers view calf weaning and rearing, and may help inform the design of future research and knowledge transfer projects aimed at improving management practices on dairy farms.

Effects of feeding different levels of dietary fiber through the addition of corn stover on nutrient utilization of dairy heifers precision-fed high and low concentrate diets

The objective of this experiment was to assess the effects of manipulating dietary fiber by replacing corn silage (CS) with lower quality forage as corn stover (CST) when used in high concentrate (HC) and low concentrate (LC) diets for precision-fed dairy heifers. Eight Holstein heifers (335.6 ± 7.41 kg of body weight) were randomly assigned to 2 levels of concentrate: HC (20% forage) and LC (80% forage), and to a forage type sequence [0% of forage as corn stover (CST), 100% corn silage (CS); 20% CST, 80% CS; 40% CST, 60% CS; and 60% CST, 40% CS] within concentrate level administered according to a split-plot, 4 × 4 Latin square design (21-d periods). Heifers fed HC had higher apparent total-tract dry matter digestibility (DMD). Increasing the fiber level by increasing the amount of CST in the diet resulted in a linear decrease of DMD and organic matter digestibility. Heifers fed LC diets had higher neutral detergent fiber (NDF) digestibility and tended to have lower acid detergent fiber (ADF) digestibility than those fed HC diets. Substituting CS with 20% CST resulted in the highest NDF and ADF digestibilities. Digestibility of N was not different, but N retention increased for HC and decreased quadratically for LC diets. Heifers fed HC diets decreased fecal output, and CST linearly increased these parameters. Urine volume tended to be higher for HC-fed heifers, and increasing dietary fiber through CST inclusion tended to decrease urine output. This shift in water excretion resulted in similar total manure output. Total purine derivative excretion did not differ between treatments, but interacted with CST addition, resulting in a linear increase in microbial protein flow to the duodenum in HC-fed heifers and in a linear decrease in LC diets as CST increased. In conclusion, increasing dietary fiber through CST decreased DMD and organic matter digestibility linearly, whereas NDF and ADF digestibility were maximized when 20% CST was added to HC and LC diets. Microbial protein synthesis increased and decreased linearly with CST addition in HC and LC diets, respectively. Retention of N increased and decreased quadratically with CST addition in HC and LC diets, respectively. Total manure excretion was not different between HC or LC diets.

A survey of bovine colostrum composition and colostrum management practices on Pennsylvania dairy farms

Colostrum composition and management were surveyed via sample and data collection from 55 dairy farms in Pennsylvania. Colostrum samples were analyzed for fat, protein, lactose, total solids, ash, Ig, lactoferrin, water- and fat-soluble vitamins, and minerals. Mean percentages of fat, protein, and lactose in colostrum were 6.7, 14.9, and 2.5, respectively. Concentrations of IgG1, IgG2, IgA, IgM, and lactoferrin were 35.0, 6.0, 1.7, 4.3, and 0.8 mg/mL, respectively. Mean concentrations of fat-soluble vitamins, including retinol, tocopherol, and beta-carotene, were 4.9, 2.9, and 0.7 microg/g, respectively. Mean concentrations of water-soluble vitamins were 0.34, 0.90, 4.55, 0.60, 0.15, 0.21, and 0.04 microg/mL for niacin, thiamine, riboflavin, vitamin B12, pyridoxal, pyridoxamine, and pyridoxine, respectively. Mean concentrations (mg/kg) of selected minerals in colostrum were also determined (Ca 4,716; P 4,452; Mg 733; Na 1,058; K 2,845; Zn 38; Fe 5.3; Cu 0.3; S 2,595; and Mn 0.1). The findings of this study revealed that the mean concentrations of most nutrients in colostrum have increased when compared with values previously reported. Results also showed that management practices have improved over time, particularly with regard to colostrum storage and feeding. Additionally, we observed that herd size influenced colostrum management and quality. It can be inferred, based on these findings, that although improvements have been made with regard to colostrum management and quality, there is still a need to educate producers on issues related to storage and timely feeding of colostrum to increase passive transfer and decrease the rate of calf morbidity and mortality.

A Prospective Study of Calf Factors Affecting Age, Body Size, and Body Condition Score at First Calving of Holstein Dairy Heifers

Data were collected prospectively on parameters related to first calving on 18 farms located in Northeastern Pennsylvania. This project was designed to study possible residual effects of calf management practices and events occurring during the first 16 wk of life on age, BW, skeletal growth, and body condition score at first calving. Multiple imputation method for handling missing data was incorporated in these analyses. This method has the advantage over ad hoc single imputations because the appropriate error structure is maintained. Much similarity was found between the multiple imputation method and a traditional mixed model analysis, except that some estimates from the multiple imputation method seemed more logical in their effects on the parameter measured. Factors related to increased age at first calving were increased difficulty of delivery, antibiotic treatment of sick calves, increased amount of milk or milk replacer fed before weaning, reduced quality of forage fed to weaned calves, maximum humidity, mean daily temperature, and maximum ammonia levels in calf housing areas. Body weight at calving tended to increase with parity of the dam, increased amount of grain fed to calves, increased ammonia levels, and increased mean temperature of the calf housing area. Body condition score at calving tended to be positively influenced by delivery score at first calving, dam parity, and milk or milk replacer dry matter intake. Withers height at calving was positively affected by treatment of animals with antibiotics and increased mean temperature in the calf area. This study demonstrated that nutrition, housing, and management factors that affect health and growth of calves have long-term effects on the animal at least through first calving.

Feed bunk length requirements for Holstein dairy heifers

The objectives of this study were to determine the necessary feed bunk length per heifer and to assess the feeding behavior of heifers fed from bunks of varying sizes. Heifers in three age categories were used for three 16-wk experiments. In Experiment 1, feed bunk lengths per heifer were 15 or 31 cm, and, in Experiments 2 and 3, the lengths were 15, 31, or 47 cm per heifer. Heifers were fed a total mixed ration at restricted intakes. Within-group growth analyses showed uniform growth rates for all heifers at all feed bunk lengths. Individual heifer growth within each group did not vary significantly for either length used in Experiment 1. In Experiment 2, heifers fed from a 15-cm bunk had more variation in live weight gain than did heifers fed from 31- or 47-cm bunks. Live weight gains of heifers fed from a 31-cm bunk varied more than those of heifers fed from 15- and 47-cm bunks in Experiment 3. The mean number of eating bouts and meals and the mean meal duration showed differences between the 15-cm feed bunk length and the 31- and 47-cm feed bunk lengths in Experiments 1 and 2. In Experiment 3, this behavior was different across all lengths. Based on growth responses and feeding behavior, heifers that grow rapidly and that are fed a high quality total mixed diet in a free stall or a bedded pack group housing system require 15-, 31-, and 47-cm feed bunk lengths at 4 to 8, 11.5 to 15.5, and 17 to 21 mo of age, respectively.

A study of the use of milk replacers for dairy calves in the United States

This study focused on aspects of the National Dairy Heifer Evaluation Project that involved neonatal feeding practices and types of milk replacers utilized on dairy farms. Types of milk replacers and the management practices associated with their feeding were studied. Nearly 60% of US dairy farms use milk replacers for some or all of the feeding program for neonatal calves. Regional differences existed in the types of liquid feeds and milk replacers fed to calves. Western producers fed less milk replacer, and western and northeast producers fed replacers with less total CP. Many characteristics of management utilized along with these products reflect accepted management and nutrition practices. During the study period from 1991 to 1992, 11.2% of replacers contained casein. A greater proportion of these were found in the West during the first 6 mo of the study, reflecting changes in the milk replacer formulations during that time.

Alberta dairy farm survey response

All dairy producers in the Canadian province of Alberta were mailed a questionnaire to determine current management practices and production. This survey was undertaken to develop and to plan extension programs based on current dairy producer needs. Of the producers contacted, 802 (57%) responded to the survey questionnaire. The results indicated that the mean herd size was 67 cows, and mean daily milk production was 21.9 kg/d per cow. More than 60% of the producers reported that the majority of their calf losses occurred at birth, and another 15.6% stated that losses occurred within the 1st wk. Less than one-third of the cooperators individually penned calves to prevent contact among calves prior to weaning. Approximately 31% of the cows in the herds surveyed required two or more breedings, partially because of inadequate estrus detection; only 50.3% of the respondents had daily scheduled detection times. The most frequent health concerns perceived by the producers were mastitis, foot problems, and silent estrus. Educational and extension programs should focus on specific areas, such as newborn calf management and reproductive management, to improve the efficiency and profitability of dairy production in Alberta.

Blood, growth, and other characteristics of special-fed veal calves in private cooperator herds

The objectives of this study were to determine the mean values for mortality, blood, and growth traits and the correlations among blood and growth traits on privately owned farms producing special-fed veal. Mortality percentages were available on 13 groups of special-fed veal calves (n = 1403) from four farms; growth and some blood traits were available on 9 groups from four farms (n = 975). Mean mortality percentages for periods 0 to 2, 2 to 7, and 7 to 16 wk, and over 16 wk were 1.0, 1.0, 1.0, and 3.1%, respectively. Means for average daily gain for 2 to 7 wk were 1.37 +/- .008 kg and for 7 to 16 wk were 1.52 +/- .001 kg. When calves arrived at the veal farm, total plasma protein averaged 6.2 +/- .05 g/dl. Examination of total plasma protein upon arrival of calves indicated that 81% of the calves had received colostrum. The base level indicating colostral deficiency was < 5.5 g/dl of total plasma protein; 51% of the calves had total plasma protein > 6.0 g/dl at arrival. Mean hemoglobin concentrations at arrival and at 2, 7, and 16 wk were 11.1 +/- .15, 10.6 +/- .18, 9.2 +/- .14, and 7.8 +/- .13 g/dl, respectively. Means for hemoglobin were generally higher than previously reported for special-fed veal calves reared in individual stalls. Hemoglobin and red blood cell counts were correlated positively with 16-wk average daily gain and body weight, and midtrial white blood cell counts were correlated negatively with average daily gain and body weight from 2 to 7 wk; there were no other significant relationships between blood traits and growth performance measures.

A demonstration project of interdisciplinary dairy herd extension advising funded by industry and users. 3. Impact on management practices

The objectives of this 24-herd, demonstration project of integrated problem solving and extension advising were 1) to evaluate dairy production management practices, 2) to formulate recommendations for guiding producers to correct management deficiencies, and 3) to measure the rate of practice adoption. Management evaluations focused on herd nutrition and forage crops, mastitis control and milking equipment, reproduction, and herd health. Sixty-eight management practices or milking equipment components were evaluated on each farm. A total of 216 recommendations were made in nutrition and forage crops as follows: calf and heifer management, 89; forage crops, 73; dry cows, 26; lactating cows, 19; and general, 9. The least adopted suggestions for nutrition and crops were for forage crop management. A total of 283 recommendations were made in mastitis management or milking equipment as follows: milking practices, 90; milking equipment, 90; general mastitis control, 61; environment, 32; calf management, 9; and stray voltage, 1. Producers most resisted updating and maintaining milking equipment within the milking management area. Detection of estrus was the focus of reproductive management advising. A total of 80 practices were recommended as follows: one person responsible, 24; specific location, 24; specific time, 24; and regular veterinary visits, 10. Designation of a specific site was the least adopted of these recommendations. Overall, 419 of 581, or 72%, of all recommendations were adopted.

The National Dairy Heifer Evaluation Project: a profile of heifer management practices in the United States

The National Dairy Heifer Evaluation Project was a cooperative, USDA-sponsored project involving state agricultural departments, the Cooperative Extension Service, the National Agricultural Statistics Service, and the Animal and Plant Health Inspection Service. A series of retrospective and prospective descriptive surveys using a multiple list and area frame sampling technique were conducted. Information collected pertained primarily to dairy neonates and replacement heifers. Much of the study was related to observational information on health and management characteristics that can be related to the animals' long-term physical and economic performance. The data reflect herds representing 78% of the national dairy cow population. Average herd size was 86 milking and dry cows and 66 heifers. Many characteristics of these herds reflect accepted and recommended practices in the area of dairy replacement management and nutrition. Data summarized in this national study can be utilized to evaluate the impact of management practices on dairy operations.

Initial results of a statewide extension program in calf and heifer management in Pennsylvania

This study was designed to evaluate changes in calf and heifer management in a sample of Pennsylvania dairy farms in conjunction with a statewide extension program on dairy replacements. The extension program reached dairy farmers in addition to individuals in agribusiness, veterinarians, and others who have frequent contact with dairy farmers through a multiplicity of information channels. An extensive survey was conducted during the 1st yr of the project on 329 commercial dairy farms throughout Pennsylvania. The same farms were contacted 2.5 to 3 yr later for comparison. Most (84.7%) of the farmers in the original random sample learned new information about calf and heifer management during this time, and 77.3% reported that they received all or part of this new information from extension. Sources of information most often used by the farmers in this study were dairy magazines, extension newsletters, and meetings organized either through extension or agribusiness. Adoption by farmers of many of the targeted practices specific to calving management, preweaned calves, and health management increased over this period.

Characterization of the management practices of the top milk producing herds in the country

Out of 128 surveys mailed to dairy farms that had been identified by the nine DHI processing centers as the top milk producing herds in the country, 61 surveys were returned. The predominant forage being fed was corn silage, followed by legume hay and haylage. On average, 6.7 feed additives and 3.5 alternative feeds were fed. Producers reported the following incidences of metabolic disorders: parturient paresis, 7.2%; displaced abomasum, 3.3%; ketosis, 3.7%; and nonspecific downer cow syndrome, 1.1%. Producers scheduled detection of estrus 3.1 times per day. Only 18.3% of the herds used routine synchronization of estrus. Artificial insemination was used on 94.8% of the cows and 88.5% of the heifers. The most important trait in sire selection was PTA for milk. For mastitis control, 75.4% of the producers practiced predipping, 85.2% used individual paper towels, 93.4% practiced postdipping, and 95.1% treated all cows at cessation of milking. Increased profitability and lower costs or higher returns were the primary motivators of these producers. Veterinarians were the most frequent source of information, followed by farm magazines. Satellite delivery of educational programs was the least acceptable delivery method. Extension professionals need to be cognizant of the producers' preferred information sources and delivery systems to ensure accurate, timely, cost-effective transfer of technological advances.

Raising dairy replacements to meet the needs of the 21st century

Producing high quality replacement heifers at minimum cost will be one of the many challenges facing the dairy farm of the 21st century. Because replacement heifers represent a large portion of the total cost of milk production, dairy farmers will have to meet the replacement needs of their lactating herds at minimum cost to maintain the farm's profitability. To keep the US dairy industry competitive into the 21st century, researchers, extension, industry, and producers must examine the database of research in order to determine how to apply the known information to current production and research efforts. Important research is needed to improve the dairy heifers of the future. This review summarizes research of the past 12 yr related to dairy replacements and incorporates those findings into possible scenarios for future dairy calf and heifer management systems. Additional research is needed to determine how dairy replacement raising systems affect the lifetime productivity and profitability of the dairy cow.

Preweaning intake and postweaning dietary energy effects on intake and metabolism of calves weaned at 26 days of age

Holstein calves (n = 48) were used to evaluate whether preweaning feeding management affects postweaning DMI and metabolism after abrupt weaning at 26 d of age. Calves were fed only whole milk until d 19 of age. From d 19 to 26, calves were provided one of three isocaloric and isonitrogenous diets: milk at 15% of d-1 BW, milk at 12% of d-1 BW plus a grain-based supplement added to the pail, or milk at 12% of d-1 BW and drenched (force-fed) with the supplement. After weaning, calves were offered a low or high energy (1.7 or 5.8% ether extract) starter. From d 26 to 36, starter intake was similar between calves fed the supplement in the pail and those fed only milk but lower than for calves drenched with supplement. Plasma NEFA increased threefold from d 26 to 27, and calves fed only milk had higher NEFA than drenched calves. From d 26 to 42, plasma VFA of drenched calves were higher than those fed only milk. Except for an increase in plasma NEFA at d 36 and 42, high energy starter did not affect any variable. Preweaning drenching of calves stimulated postweaning adaptation to dry diets. Intake postweaning appears to depend more on physiological adaptation to dry diets than a preweaning feeding management.

Evaluation of starter diet crude protein level and feeding regimen for calves weaned at 26 days of age

The objectives of this study were to evaluate two levels of CP in starter diets offered to calves weaned on d 26 and to compare postweaning intake of starter diets and performance of calves weaned at 26 or 42 d. Forty Holstein calves were housed in individual outdoor hutches and assigned to one of four treatments. Treatments consisted of weaning on d 26 after offering a 20% CP starter diet from d 1, or d 21, or after offering a 25% CP starter diet from d 21, or weaning on d 42 after offering a 20% CP starter diet from d 1 (control). Between d 42 and 84, calves were commingled in outdoor group pens. On d 42, BW of control calves was heavier than that of early weaned calves. On d 84, BW did not differ among treatments. Consumption of starter diet was not affected by the age at which it was first offered. Weaned calves consumed more starter diet than controls from d 29 to 42. Postweaning performance was not affected by increasing CP in the starter diet. Weaning treatment did not affect the incidence of scours. Comparison of CP intakes with current NRC recommendations suggests that CP requirements for young milk-fed calves are adequate.

Evaluation of decoquinate or lasalocid against coccidiosis from natural exposure in neonatal dairy calves

Forty-one Holstein and Brown Swiss calves were raised as herd replacements under conditions in which they were allowed natural exposure to sporulated coccidial oocysts at a very early age. Two compounds previously shown to have anticoccidial efficacies, decoquinate and lasalocid, were used for this study. Calves were assigned randomly at birth to one of the treatments: decoquinate (approximately .5 mg/kg of BW) or lasalocid (approximately 1.0 mg/kg of BW) or to remain as unmedicated controls through 16 or 24 wk of age. Counts of fecal oocysts were reduced in the calves fed decoquinate for wk 4 to 8 and for both treated groups for wk 9 to 24. Calves fed decoquinate had increased BW, heart girth, and height at withers during wk 5 to 8. Both treated groups had higher gains than untreated calves during wk 12 to 16 with the decoquinate group larger than the lasalocid group. Feeding an anticoccidial compound to newborn calves reduced severity of coccidiosis when early natural exposure occurred.

Influence of decoquinate fed to neonatal dairy calves on early and conventional weaning systems

Forty-four Holstein calves were assigned randomly to treatments in a 2 x 2 factorial arrangement of weaning age (4 or 7 wk) and coccidiostat (treatment or control). The objective of this study was to compare the effectiveness of a coccidiostat, decoquinate, on health parameters and growth of neonatal dairy calves on early and conventional weaning systems. Calves weaned at 4 wk had greater intakes of grain in wk 5 to 7 than did calves weaned at 7 wk. Differences in intakes between weaning groups were not apparent from wk 8 to 24. Fecal coccidia oocyst counts were not affected by age at weaning but were affected by coccidiostat feeding at the rate of .5 mg/kg BW/d offered from 3 d of age and throughout the trial. No effects due to age at weaning or coccidiostat treatment were found in plasma glucose, urea N, and minerals (Ca, P, Na, Cl, K, Mg). Growth parameters were significantly increased in treated animals. Total BW was increased (wk 9 to 24) in treated over control calves (127.3 versus 118.5 kg). Height at withers was also increased in treated calves (95.0 vs. 92.8 cm). Coccidiosis treatment increased growth of dairy calves from 9 to 24 wk, but no interactions were found between coccidiosis treatment and age at weaning.

Survey of calf and heifer housing on Pennsylvania dairy farms

Research has established a link between calf and heifer housing and calf health. To determine current calf and heifer housing practices in Pennsylvania, 329 dairy farms were surveyed. The study was designed to increase awareness on the part of dairy farmers in housing and management and to develop education programs and materials in the area of calf and heifer management. All surveys were conducted on the farm by personal interviews. Results showed 24.9% of the farms had maternity pens in a building separate from the milking herd, although half of these farms used maternity pens in conjunction with facilities of lesser quality for the health and management of the animals. The same number of farms used calf hutches as those keeping calves in dairy barns with cows. A high percentage of the farms weaned calves (moved from milk diets to dry feed diets) to recommended types of facilities that included group pens, loose housing, and group or superhutches. However, 49.5% of the facilities used for weaned calves were in conjunction with other dairy animals. Animal restraint facilities have also been identified as an area that needs more emphasis on dairy farms. Many areas of dairy replacement housing on commercial dairy farms were determined to be unsatisfactory according to recommended Pennsylvania standards.