DAIRY
C. W. Arave
Department of Animal, Dairy, and Veterinary Sciences
Utah State University
Logan, Utah 84322
current address:
1460 East 1200 North
North Logan
Utah 84341
and
J. L. Albright
Department of Animal Science
Lilly Hall, Purdue University
West Lafayette, Indiana 47907
In 1980, the Humane Society of the United States (HSUS) developed a grading system of farm animal products for "conscientious omnivores." It categorized dairy products as acceptable, stating that "dairy cattle are the least intensively raised and confined of all farm animals" (49).
About 2 years later, M. Fox (36) of HSUS listed several concerns about the welfare of dairy animals. He cited the major issue as "reduction of quality and quantity of individual attention" in larger herds. The other welfare issues were:
Similar concerns were expressed during a meeting of the Livestock Conservation Institute, reported by N. Black (17). (Castration was an additional concern).
Many animal rights activists and others have also identified the following issues or concerns:
DISCUSSION
The issues raised by M. Fox (36) provide a good framework for looking at current practices and alternatives in the dairy industry.
Reduction in the Quality and Quantity of Individual Attention
In 1979, there were about 11 million cows on 352,000 dairy farms, an average herd size of 30 cows (27). In 1989, there were 10.1 million cows on 205,000 dairy farms, an average of 49 cows per herd (90). Forty-six percent of U.S. cows were enrolled in a testing program, and the average size of these herds was 83 cows (60). In New York State, annual labor per cow decreased from 91 hours (h) in 1956 to 50h in 1978 (66). Milk yield per cow increased from 5,842 to 11,239 pounds (2,650 to 5,098 Kg) during this period in the United States. Cost of labor per cow averaged $114 (or about 23h/cow) in Virginia DHI herds in 1989 (97). These trends were the result of increased mechanization, especially in forage and waste handling, improved milking parlor design, computerized rations and feeding systems, and continued genetic increase.
Management practices have not reduced the quality of cow care; for example, an evaluation of management on southern dairy farms showed that milk yield per cow improved as farmers employed more of the recommended management factors (22). "A typical dairy farmer using all the management practices had a larger herd producing above the average, was younger than average, was in a farm partnership, and had a college education" (22). Herds with excellent mastitis control had larger milking parlors and greater efficiency (cows milked/man/hour) than herds with fair mastitis control (35). Mechanism and automation have allowed dairy producers to pay more attention to management practices such as teat dipping (pre- and post-milking) and dry cow therapy for mastitis control (effectively reducing mastitis to about 7 percent of quarters (63)).
Transportation of Injured and Sick Animals to Slaughter
Even though practically all dairy animals are transported sometime during their life (95 percent by truck (2)), relatively little legislation (Animal Transportation Act, 1906, 28-hour law (Public Law #340)) or research has addressed the effects of transportation. When Jersey bull calves were transported, they had greater heart rates when they were free to move about than when they were confined to wood crates (83). Beef heifers that were crowded during transit had heart rates that were 4 to 7 percent lower than heifers that were provided with ample space (30); however, carcass bruising increased with stocking density changes from low (3m2/head) to high 1m2/head).
Additional physiological and behavioral studies involving calves indicate that transportation adversely affects welfare (86). Reducing time in transit, providing feed and water, avoiding extremes in weather, avoiding both weaning and vaccinating immediately before travel, avoiding exposure to unfamiliar animals, and same sex grouping during shipping should prevent or alleviate some stress (21). Injured or sick animals are particularly at risk in transit. An estimated 75 to 80 percent of the nonambulatory animals arriving at stockyards are large dairy animals. Nonambulatory cattle accounted for 0.1 percent of the cattle received at United Stockyards (S. St. Paul, Sioux Falls, Sioux City, Omaha, St. Joseph, Indianapolis, and Milwaukee) but these stockyards will no longer accept nonambulatory cattle (7).
Dehorning, Castration, Identification
Dehorning is a generally recommended practice that reduces injuries to both animals and handlers, bruising during transport, and aggressive behavior in grouped cattle (85). Use of a commercial electric iron for dehorning of calves under 30 days of age is the most popular method (15), and presents no long-term stress (55). Caustic potash works well on calves from 1 to 3 weeks old, but it must be applied carefully. A dehorning tube may be used on calves up to 45 days of age. Saws, dehorning clippers, and Barnes dehorners are commonly used to dehorn older cattle (31). Calves ages 7 to 16 weeks apparently did not benefit from a lidocaine block before dehorning (18). A veterinarian should anesthetize the base of the horn before dehorning adult animals. In one study, adult cattle (18 to 22-month-old heifers) dehorned using either electro-immobilization, a local anesthetic, or no anesthetic were compared to a control (non-dehorned) group. Serum cortisol levels rose significantly in dehorned heifers, but there were no significant differences by type of dehorning (23).
Castration is used to control aggression (39, 42), reduce injury, increase growth efficiency and increase market price at slaughter (19). The most common methods of castration are surgical (cutting about 1 cm away from the bottom of the scrotum, gripping the testicle, and removing it with a quick jerk), emasculator (the spermatic cord is severed without breaking the skin), and elastrator (applying a rubber band above testes, stopping blood flow to the testes) (16). Surgical castration causes less pain than the latter two methods (74). Breaking rather than cutting the cord during surgical castration causes the lumen to close and prevents bleeding. Calves are usually castrated when they are dehorned, i.e., before 45 days of age. Males exhibit fewer and less intense secondary sexual characteristics, including aggressive behavior, after they are castrated. Animal welfarists criticize the failure to administer anesthesia during castration, but as Friend (42) points out, "not using anesthetics for those relatively simple procedures greatly reduces the complications caused by the anesthetics," i.e., bloating and longer restraint with resulting stress. Injecting a lactic acid solution into the testes is an alternative method. In one experiment, 40 calves chemically castrated had less scrotal edema and gained more weight to 28 days, but weaning weight and 196-day weights were not different from surgically castrated calves (48). Cohen et al. (25) concluded that surgical castration caused greater stress than chemical castration. Over a 133-day period, there were no differences in the average daily gain of intact and castrated calves, but average daily gain of chemically castrated calves exceeded that of surgically castrated calves.
Dairy animals must be permanently identified for production, health, and registration records. Metal and plastic ear tags, tattoos, and hide brands are commonly used. Animal rights activists have strongly criticized use of hot hide face branding during the whole-herd buy-out program. Hot branding is a "prohibited operation" under provisions of the UK Welfare of Livestock Regulations (33). Freeze branding is less painful than hot branding and produces little hide damage, although it is visible at a distance (57, 59). Implanting a transponder just under the skin is the latest type of permanent identification. Destion/IDI markets more than 2.5 million transponders annually world-wide (5).
Prolonged Stanchion Tying of Cows, Especially Without Exercise
Stanchion or tie-stall housing protects cows from weather extremes, predators, and disease, lets dairymen provide more individual care, and is a location for milking. About 60 percent of dairy farms are located in the Great Lakes and Northeastern States, of which about 70 percent have stanchion barns (51). Stanchion and tie-stall barns made up 56 percent of U.S. dairy housing in 1958 (70); this proportion decreased to 29 percent by 1975 (51). The increasing popularity of the free stall, which was invented in 1960 (2), has contributed to the decline in stanchion housing. Free stalls save labor and bedding and are more suited to larger herds than tie stalls. Cows in free stalls may exercise at will. Most dairy operators turn cows out of stanchion barns one or more times daily for milking, to allow the cows to exercise, and to observe the animals for estrus (92). Cows in loose housing on deep litter rested longer than cows in free stalls or tie stalls, as did cows provided with a larger resting area, which also reduced aggression. Slatted floors in loose or free-stall housing may be used to conserve bedding and eliminate frequent manure handling. Urine and sloppy manure are immediately removed. Performance suffers, however, and cows can be injured if units are poorly designed (12,75,94). Waffle slats offer surer footing and stay cleaner (29). Cows in comfort stalls, which are longer and wider than tie stalls, spent more time lying (10.2h) than did cows in tie stalls (8.8h) (70). Dry cows and heifers spent 8.9 hours per day lying (11); lactating cows in free stalls spent 11.3 hours per day lying. Two-year old cows in tie stalls and mature cows in free stalls spent similar amounts of time lying (65). Cows need 10 to 12 hours of resting time in each 24 hours (94). A tie stall on wheels, the "Unicar," was an experimental housing, milking, and management system (20,71,81) that was never used in the United States and was used only experimentally in Europe.
An emerging issue in the United States is the docking of cows' tails. The practice has been limited primarily to cows milked in rotary and parallel parlors to prevent disease, improve hygiene, and enhance ease of milking from the rear (50). The practice originated in New Zealand to keep dirty tails from impeding the milking process for pastured animals milked in rotary parlors (1). The general effects of this procedure on the cow's well-being and behavior need to be studied.
Pasturing would supposedly reduce stocking density, environmental pollution (waste disposal, undesirable odors), and energy costs, and would permit housing to be used for shorter periods (87). Many dairy managers continue to pasture dry cows and heifers, but the trend is toward dry-lot management of the milking herd. Rollin (72) noted that legislation in Sweden that granted cattle the right to graze indicates that "U.S. society will soon demand that agriculture back off, at least to some extent, from confinement and pay greater attention to agricultural animal comfort and happiness."
Pasturing has its problems, however, and may not be as ideal as animal rights activists perceive. Weather limits the grazing season (150 days or less) in several Northern States. Pasture will not supply the nutrients needed to maintain high milk yield, because it is difficult to provide forage of uniform quality and quantity. Shade and water, heat, insects, susceptibility to bloat, energy expended in grazing and travel to the milking parlor, and toxicity from soil are other considerations associated with pasturing. For example, high-producing cows spent much less time lying down and significantly more time grazing at all stages of the grazing season (10).
Calves have little circulating antibody at birth and need colostrum to provide passive immunity (67). There is no consensus on how to provide colostrum: the calf can nurse the cow for 4 days (31); after initial nursing or hand-feeding, the cow and calf can be separated within 24 to 48 hours and colostrum can be bucket-fed (15); the calf can be moved at birth (or when dry in winter) to a calf hutch (4). At 12 to 24 hours after birth, blood immunoglobulin levels tended to be higher in calves fed colostrum 1 to 2 hours after birth than in those fed colostrum 6 or 12 hours after birth. "There was no meaningful relation between calf mortality and the time cow and calf remained together (r= -.14, n = 106)" (34). An account of Camargue cows, a breed found in southern France, indicates that a cow leaves the herd to give birth, hides the calf for the first 3 to 4 days, and returns only to nurse it for short periods. Calves then join a subgroup of young animals, which tend to play and sleep together. Nursing appears to be a community activity, as most dams nurse their calves about the same time. Calves travel together when the herd moves (26). A cow and her calf usually bond shortly after birth; however, it is not unusual for cows to accept nursing by several calves (43). Suckled Friesians weaned at 7 months and transported to new housing required longer to habituate to the new environment than did artificially reared Friesians (4 vs 2 days). However, previous rearing did not appear to have any long-term effects on behavior (91).
Neglect of "Unwanted" Bull Calves
Newly born bull calves a few days old are generally transported to slaughter, to auction, or to ranches specializing in rearing dairy beef or veal. Holstein bull calves are becoming popular feedlot animals. One broker handles 45,000 per year and raises an additional 5,000 female dairy calves (82). Dairy operators may turn rearing of male and female calves to specialists due to limitations in labor, land, and facilities. Recommended care for surplus calves includes the following:
Diseases are easier to control and intersucking can be avoided when calves are raised individually. Outdoor hutches are becoming increasingly popular because is it difficult to properly regulate air and humidity in enclosed housing (4). However, calves are reared in warm, enclosed barns; cold, enclosed barns; open-front barns; various types of hutches; and on nurse cows (4,15,31,67,74). Individual pens (either in enclosed or open housing) were the most common method of rearing calves (53 percent), and group pens were the least common method (12 percent); some dairies combine both types of rearing (calves were kept inside for a few weeks and then moved to outside hutches (35 percent).
Calf losses were substantially higher in herds where calves were reared in enclosed housing (95). Calves reared in groups consumed solid feeds at an earlier age and had higher average daily gains (ADG's) than calves raised individually (93). However, in a study involving six pairs of monozygous twin heifers, feed intake and ADG to weaning did not differ when one twin heifer was reared in a group and the other was raised in a hutch (69). Physiological data indicated a decreasing gradation of stress to calves raised in individual stalls, individual pens, hutches, and group housing (40). Calves in individual stalls and pens were on wooden slats, however, while hutch and group calves were on a dirt base. Rearing calves with nurse cows is a more common practice in beef production. The number of calves must be adjusted to the milk yield of the cow. The cow usually must be restrained before it will accept nursing by strange calves. Proponents of the system claim it offers labor savings and a lower incidence of digestive upsets and bacterial infections (74).
Failure To Use Welfare-Related Research Knowledge
In the opinion of the HSUS's Fox, "the welfare of dairy cows, especially in small and medium-sized, owner-operated herds, is generally far superior to that of other farm and animal species" (36). Research studies on welfare-related topics "reflect the close correlation between welfare and maximizing individual productivity" (36). The 1988 "Guidelines for Dairy Cattle Husbandry" (3) were based on current practices and research data. The guidelines also illustrate the diversity of management facilities and practices. While it may be feasible to immediately adopt improved animal-related practices, changing the cow's physical environment according to all the latest research recommendations may not be feasible. Economics dictate that most capital facilities be depreciated over several years.
Production-related Susceptibility to Disease and Metabolic Disorders
The average cow in the United States today produces about six times more milk than the average cow did at the turn of the century (6,655 vs. 1,136 kg) (58,88). Cows in some herds produce more than 11,000 kg of milk. Worldwide, milk per cow continues to increase about 1.25 percent yearly, which may make future cows even more susceptible to metabolic disorders (58). However, this increase was possible only through improved genetics, artificial breeding, nutrition, disease control, and management. The ratio of milk cows to human population in the United States has decreased from 1:5.6 (1940) to about 1:27 today. There is no evidence that the genetic increase has plateaued (individual cows have produced more than 63,000 pounds (28,600 kg) of milk. To remain competitive in a free-market economy, dairy managers will continue to rely on genetic improvements, least-cost balanced rations, disease control, and improved cow comfort.
Ketosis, one of the most important metabolic diseases of high-producing cows, has an incidence of about 4 percent (58). It may be induced by a prolonged energy deficit plus an influx of the precursor of ketosis, and may be reversed by effective treatment (62). Preventive measures include use of rations that prevent cows from becoming excessively fat before they calve and feeding of concentrate with adequate amounts of high-quality forage after calving. Measures to prevent ketosis should also reduce the incidence of displaced abomasum, which is apparently caused when dry cows or cows in early lactation are fed excessive concentrates and insufficient dietary fiber. Proper rations can also help prevent milk fever, a disease whose incidence increases at the fifth or sixth lactation. Feeding a diet low in calcium at least 5 days before calving stimulates the parathyroid in preparation for the increased needs for parathyroid hormone and 1,25-(OH)2D after calving (58).
CONCERNS EXPRESSED BY ANIMAL RIGHTS ACTIVISTS
Separation of Cow and Calf at Birth
The need to separate dam and young at birth has been noted, but activists' description of both animals as being in a state of "anguish" (46) or anxiety is not universally accepted (73). Separation soon after birth is common in cattle, an "outlying species". Before grazing, cattle mothers, given the opportunity, "hide" their young for up to several hours at a time. Maternal instincts have not been a focus of selection in dairy cattle, because of the emphasis on milk production; consequently, bonding between dam and young may not be as strong as in beef cattle or other species. Emotional upset may be lessened by early separation, before bonding has occurred. Intimate human contact during the critical period improves ease of handling and milking temperament (26).
For 305 days, an average dairy cow produces at least six times as much milk as a calf needs daily. Artificially reared dairy calves are usually weaned by 70 days. A calf allowed to ingest excess milk is likely to experience diarrhea and death.
Some activists object to the fact that nearly continuously pregnant cows are constantly burdened with carrying large quantities of milk. Most dairy operators strive for a calving interval of 2 months, but this goal is rarely achieved. Estimated economic losses due to excessive days open (more than 90 days) are $1.22 per day (56). Inducing lactation using hormone treatment has been about 70 percent successful, but lactation yields were only 70 percent or less than that achieved in previous years (32). The induction of ovulation has been associated with side effects such as abnormal estrous behavior, reduced fertility, cystic follicles and corpora lutea, and chronic vaginal prolapse. Treatment with estrogen reduced abnormal estrous behavior, but milk yields were only 20 percent of normal (78).
An average cow carries 5 lbs. (11 kg) of milk in her udder at milking time if milked twice daily. This is about 1.6 percent of her body weight (equivalent to about 2 pounds for a 120-pound human). Cows in many high-producing herds are now milked 3 or 4 times daily, leaving less milk in the udder than twice-daily milking. Cows spend about half the day lying down, which relieves strain on muscles and ligaments that support the udder weight. Beef calves suckle only about 5 times per day (43,54).
Few cows live to be 15 years of age. A 27-year-old Holstein cow in Wisconsin generated considerable publicity when she died, after giving birth to 22 calves in her lifetime (13).
Records of nearly 300,000 Holstein (the predominant U.S. breed) from 1966 to 1986 indicated that average herd life was 3.4 lactations (64), which means cows leave the herd at about 6 years of age. The average age reported in Wisconsin Holstein herds was 5 years (76). Herd life was positively correlated with production during the first lactation. More than 56 percent of cows culled in the first lactation were culled because of low production (28). Nutrition affects the expression of genetic potential, age at puberty, breeding age, and calving age and is the most important environmental factor influencing life-span within the herd (31). Lower production, slower increases in herd size, shorter first calving intervals, and longer subsequent calving intervals explained 70 percent of the variation in the average age of a herd (76). All of these factors except shorter first calving intervals would tend to lower income. Reducing incidence of disease (including mastitis), injury, and reproductive problems would contribute to an opportunity to increase average herd age.
Use of Drugs to Maintain Health, and Antibiotics as a Regular Feed Additive
Antibiotics are commonly used in calf feeds until the calf is about 4 months old to improve growth, reduce the incidence of scours, and improve appetite (15,31). Feeding antibiotics to adult cows is not recommended (31). Antibiotics have greatly reduced the incidence of contagious diseases of cattle, some of which endangered human health (53). Antibiotics have been used for more than 30 years to prevent and treat mastitis, but care must be taken to avoid residues in milk or meat. In 1990, the Milk Industry Foundation tested more than 2 million tankers and detected drug residues in only 0.1 percent of them. Delegates at the 23rd National Conference on Interstate Milk Shipment (April 1991) adopted strict measures to ensure that no antibiotic residues enter the milk supply. Every load of Grade A milk is screened. If residues are detected, the milk is discarded and violators are not allowed to ship milk for 2 days (or if a second offense, 4 days). If there are three violations in a year, the regulatory agency may revoke the violator's Grade A permit (77). Tranquilizers are not used, as some critics allege, nor are hormones implanted to promote milk production.
Large farms (those having $250,000 or more in gross sales in 1990) represent less than 5 percent of U.S. farms. The average farm was 429 acres in 1978 and 461 acres 12 years later -- an increase of less than 3 acres per farm per year. There were 170,000 fewer farms in 1987 than in 1978, but 88.5 percent were fully or partly owner operated -- an increase of .8 percent from 1978 to 1987 (89).
Detrimental New or Prospective Technology
Superovulation and embryo transfer of genetically superior donor cows can significantly improve reproductive rates. The total number of possible ova a cow may ovulate in her lifetime is 21,000 (15). Embryos resulting from repeated superovulation can be split and frozen for future use. In one study, only 43 superovulated donors yielded transferable embryos (6.2/donor) (9). The number of transferable embryos ranged from 5.3 with the first flush to 2.2 on the fifth flush (14). Cows have been superovulated eight times at 50-day intervals and still responded to superovulation (80). There may be a viable alternative to superovulation involving the puncturing of bovine follicles during transvaginal ultrasound scanning, retrieval of oocytes by aspiration, and in vitro maturation and fertilization of oocytes prior to transfer. The procedure does not interfere with the cow's normal reproductive cycle. It is estimated that 30 transferable embryos could be obtained from the 135 oocytes available per animal in a year (68). Embryos are transferred to recipient cows, usually by nonsurgical techniques similar to those used for artificial insemination (80). There is no evidence that embryo transfer increases the incidence of difficult births. Several factors are associated with difficult births, including those associated with the calf (size, sex, multiple births, malpresentations, and stillbirth) and the dam (body weight and size, pelvic area, and age or parity of dam)(84). The heritability of birth weight (about .45) indicates more than half the variation is due to nongenetic influences. The calving ease scores of bulls used in AI enable breeders to select for that trait.
Bovine somatotropin (BST) has recently been approved by FDA, but is not at this time extensively used in the dairy industry.
It is estimated that cattle produce about 1.8 percent of the methane in the upper layer of the atmosphere (61). Cows lose about 6 percent of their energy as methane. Losses are about 2 percent for cattle on high-concentrate diets and as much as 12 percent for cattle on all-forage diets. Covering of manure lagoons to trap methane (and control odor) could yield useable energy and substantially reduce methane emissions from livestock. The use of BST would mean that 11 percent fewer cows would be required for the current level of milk production. In turn, this would reduce inputs (feed, 9 percent; nitrogen and phosphorus, 10 percent; cropland, 6 percent; irrigation water, 9 percent; fossil fuel, 12 percent), waste products (urine, 5 percent; manure, 8 percent; methane, 8 percent), and soil loss (5 percent) (52).
Pollution of air, water, and soil has been a concern, especially for larger dairies, since the early 1970's. Registration of facilities and a permit to operate, depending on size of operation (more than 700 mature dairy cows), are required by the U.S. Environmental Protection Agency (EPA) and various State counterparts. These help to ensure that dairy wastes are properly handled (31).
A return to "green pastures" (38) might distribute animal waste more evenly, but more land and cattle would be required to produce the 148 billion pounds of milk currently consumed in the United States. In New Zealand (NZ), where almost all cows graze pastures, average milk production is 3,346 kg milk/cow vs. 6,461 kg in the United States. (89). Milk production by AI daughters of U.S. and N.Z. bulls was almost equal when they were milked in a common environment (4,174 vs. 4,015 kg milk and 163 vs. 161 kg fat for U.S. and N.Z. respectively in Polish tests (41)). Public attitudes are the major obstacle to utilization of waste. Animal waste may be used as fertilizer, bedding material, feed supplement, and (as biogas) for energy production.
Ensiled, dehydrated, or mechanically (aerobically) digested manure is no longer an air pollutant and has a chemical composition similar to that of the original feed. Waste from other species can be used as a high-quality ingredient in dairy rations (8).
Some animal rights activists advocate restricting animal or human populations to a size that will enable them to be fed strictly from plant source foods (47,96). An official with the American Medical Association noted that it would be difficult to receive the minerals, vitamins, and other nutrients recommended by the National Academy of Sciences without regular consumption of meat and dairy products (6). Cropland represented about 18 percent of U.S. acreage in 1987. Pasture, including 3 percent cropland used for pasture, was 29 percent; forest land, which includes some land devoted to livestock grazing acreage, was another 29 percent (89). Ruminants (including dairy cattle) convert to human food much of the plant material on these pastures and forest lands, a resource that otherwise would be wasted. Cattle also consume many byproducts, such as cottonseed hulls, cull fruits and vegetables, brewery waste, etc., that would otherwise be discarded.
Dairy farm numbers will continue to decrease, as will man hours per cwt. of milk produced. Average herd size, milk yield per cow, and use of free stalls and/or dry lots will continue to increase. The industry will continue to meet animal welfare guidelines that now govern the use of dairy teaching and research animals (3). The animal rights/welfare movement will probably become more influential, and dairy producers should be aware of their legitimate concerns about animal welfare. New technologies will let dairy managers observe animals more closely and thereby improve management. New technology will also help researchers measure and evaluate animal stress, information that will be useful in developing computer models of the stress associated with various production practices. Drug and antibiotic residue in meat and milk will be regulated more carefully, and standards of milk quality will increase. Methods will be found to reduce pollution associated with intensive dairy farming practices. These improvements are unlikely to persuade the animal rights activists that animal agriculture should not be eliminated. Nonetheless, explaining to consumers the reasons underlying the practices employed on dairy farms and the benefits that accrue from dairy products will certainly enhance the credibility of the dairy industry.
1. Albright, J. L. 1972. To dock or not to dock tails. Hoard's Dairyman 117:420-426.
2. Albright, J. L. 1987. Dairy animal welfare: Current and needed research. J. Dairy Sci. 70:2711-2731.
3. Albright, J. L., G. W. Barr, W. W. Irish, J. L. Morrill, P. J. Wangness, and I. J. Lean. 1988. Chapter 6: Guidelines for Dairy Cattle Husbandry. Consort. Dev. Guide Care and Use of Agric. Anim. in Agric. Res. and Teach. Champaign, IL
4. Anonymous. 1990. Raising dairy heifers. Suppl. to Hoard's Dairyman.
5. Anonymous. 1990. Holstein, NDHIA to market electronic ID system. Hoard's Dairyman 135:853.
6. Anonymous. 1991. Hoard's has heard. Hoard's Dairyman 136:554.
7. Anonymous. 1991. Send the cow while she can still walk. Hoard's Dairyman 136:577.
8. Arave, C. W., D. C. Dobson, M. J. Arambel, D. Purcell, and J. L. Walters. 1990. Effect of poultry waste feeding on intake, body weight, and milk yield of Holstein cows. J. Dairy Sci. 73-129-134.
9. Arave, C. W., T. D. Bunch, C. H. Mickelsen, and K. Warnick. 1987. Factors affecting survivability of transferred whole and demi-embryos in a commercial dairy herd. Theriogenol. 28:373-382.
10. Arave, C. W. and R. Kilgour. 1982. Differences in grazing and milking behavior in high and low breeding index cows. Proc. N.Z. Soc. Anim. Prod. 42:65-67.
11. Arave, C. W. and J. L. Walters. 1980. Factors affecting lying behavior and stall utilization of dairy cattle. Appl. Anim. Ethol. 6:369-376.
12. Baldwin, B. A., J. R. Bareham, I. J. Duncan, R. Ewbank, D. C. Hardwick, and K. Vestergaard. 1981. Research and Development in Relation to Farm Animal Welfare. Birkhausser Verlag. Stuttgart.
13. Barth, R. 1977. Last calf at 27 years. Hoard's Dairyman 122:227.
14. Bastidas, P. and R. D. Randel. 1987. Effects of repeated superovulation and flushing on reproductive performance of Bos indicus cows. Theriogenol. 28:827-835
15. Bath, D. L., F. N. Dickinson, H. A. Tucker, and R. D. Appleman. 1985. Dairy Cattle: Principles, Practices, Problems, Profits. (3rd Ed.) Lea and Febiger, Philadelphia.
16. Beardon, H. J. and J. Fuquay. 1980. Applied Animal Reproduction. Reston Publishing Co., Reston, VA.
17. Black, N. 1983. Animal rights . . . An issue that won't fade away. Holstein World 28:652-653.
18. Boandl, K. E., J. E. Wohlt, and R. V. Carsia. 1989. Effects of handling, administration of a local anesthetic, and electrical dehorning on plasma cortisol in Holstein calves. J. Dairy Sci. 72:2193-2197.
19. Boggs, D. L. and R. A. Merkel. 1984. Live animal carcass evaluation and selection manual. Kendall Hunt Publishing Co., Dubuque, IA.
20. Brett, F. E. 1970. Parlor preview: Four new ones from Europe. Hoard's Dairyman 94:D8-D13.
21. Brown, D. E. 1986. Transportation stress. In Limiting the Effects of Stress on Cattle. West. Reg. Pub. #009:77-80.
22. Carley, D. H. and S. M. Fletcher. 1986. An evaluation of management practices used by southern dairy farmers. J. Dairy Sci. 69:2458-2464.
23. Carter, P. D., N. E. Johnston, L. A. Corner, and R. G. Jarrett. 1983. Observations on the effect of electro-immobilization on the dehorning of cattle. Aust. Vet J. 60:17-19.
24. Coats, C. D. 1991. Old MacDonald's factory farm. The Continuum Publishing Co., New York.
25. Cohen, R. D. H., B. D. King, L. R. Thomas, and E. D. Jangen. 1990. Efficacy and stress of chemical versus surgical castration of cattle. Can. J. Anim. Sci. 70:1063-1072.
26. Craig, J. V. 1981. Domestic animal behavior. Prentice Hall, Englewood Cliffs, N.J.
27. Crowley, J. W. and R. P. Niedermeier. 1981. Dairy production 1955 to 2006. J. Dairy Sci. 64:971-974.
28. Dentine, M. R., B. T. McDaniel, and H. D. Norman. 1987. Comparison of culling rates, reasons for disposal, and yields for registered and grade Holstein cattle. J. Dairy Sci. 70:2616-2622.
29. Dickrell, J. 1991. They don't waver on waffles. Dairy Today 7:26-28.
30. Eldridge, G. A., C. G. Winfield, and D. J. Cahill. 1988. Responses of cattle to different space allowances, pen sizes and road conditions to transport. Aust. J. Expt. Agric. 28:155-159.
31. Ensminger, M. E. 1980. Dairy Cattle Science, 2nd Ed., Insterstate Printers and Publishers, Danville, IL.
32. Erb, R. E. 1977. Hormonal control of mammogenesis and onset of lactation in cows- A review. J. Dairy Sci. 60:155-169.
33. Ewbank, R. 1988. Animal Welfare. In Management and Welfare of Farm Animals. UFAW Handbook (3rd Ed.) Bailliere Tindall, London.
34. Ferris, T. A. and J. W. Thomas. 1975. Management factors influencing calf mortality and blood immunoglobulin levels in Michigan dairy herds. Farm Science: Research Report 271, Michigan State Univ. Agric. Expt. Sta., East Lansing.
35. Fox, L. K. and C. Hutton. 1990. Dairy Management Manual. West. Reg. Dairy Publ. Com. Part I: 910.00-910.01.
36. Fox, M. W. 1983. Animal welfare and the dairy industry. J. Dairy Sci. 66:2221-2225.
37. Fox, M. W. 1984. Farm Animals. University Park Press, Baltimore.
38. Fox, M. W. 1990. Inhumane Society. St. Martins Press, New York.
39. Fraser, D. and J. Rushen. 1987. Aggressive behavior. In Farm Animal Behavior, ed. E. O. Price. The Vet. Clinics of N. Am. W. B. Saunders Co., Philadelphia.
40. Friend, T. H., G. R. Dellmeier, and E. E. Gbur. 1985. Comparison for four methods of calf confinement. I. Physiology. J. Anim. Sci. 60:1095-1101.
41. Freeman, A. E. 1981. Testing ten strains of Friesian cattle in Poland: A preliminary report, pp. 1-3. Holstein Science Report, Holstein Association, Brattleboro, VT.
42. Friend, T. H. 1990. Teaching animal welfare in the land grant universities. J. Anim. Sci. 68-3462-3467.
43. Gonyou, H. W. and J. M. Stookey. 1987. Maternal and neonatal behavior. In Farm Animal Behavior, ed. E.O. Price. The Vet. Clinics of N. Am. W. B. Saunders Co., Philadelphia.
44. Grandin, T. 1990. Calves you sell should be old enough to walk. Hoard's Dairyman 135:776.
45. Gruen, L. and P. Singer. 1987. Animal liberation: A graphic guide. Camden Press, London.
46. Harrison, R. 1972. On factory farming. In Animals, Men, and Morals: An Enquiry Into the Maltreatment of Non-humans, ed. S. and R. Godlovitch and J. Harris. Toplinger Publishing Co., N.Y.
47. Harrison, R. 1979. Ethical questions concerning modern livestock farming. In Animal Rights -- A Symposium, ed. D. Paterson and R. D. Ryder. Centaur Press Ltd., London
48. Hill, G. M., W. E. Neville, Jr., K. L. Richardson, P. R. Utley, and R. L. Stewart. 1985. Castration method of progesterone-estradiol implant effects on growth rate of sucking calves. J. Dairy Sci. 68:3059-3061.
49. Humane Society of the United States. 1980. Farm animals. HSUS, Washington, D.C. 20037
50. Jaquish, N. 1991. Tail docking means cleaner cows, lower cell counts. Hoard's Dairyman 136-708.
51. Jasiorowski, H. A. and A. J. Quick. 1987. Cattle Production Systems in Practice, pp. 269-289. In Dairy-Cattle Production, ed. H. O. Gravert. Elsevier Science Publishers B. V., Amersterdam.
52. Johnson, D. E., G. M. Ward, and J. Torrent. 1991. The environmental impact of bovine somatotropin (bST) use in dairy cattle. J. Dairy Sci. 74, Suppl. 1:209.
53. Jukes, T. H. 1985. Animal rights, antibiotics emerge as intertwined issued in FDA hearings. Feedstuffs 57:40,42.
54. Kilgour, R. and C. Dalton. 1984. Livestock behaviour: A practical guide. Methsun Publication (N.Z.) Limited, Aukland.
55. Laden, S. A., J. E. Wohlt, P. K. Zajac, and R. V. Carsia. 1985. Effects of stress from electrical dehorning on feed intake, growth, and blood constituents of Holstein heifer calves. J. Dairy Sci. 68:3062-3066.
56. Lemrick, S., C. W. Arave, R. C. Lamb, and E. B. Godfrey. 1987. Economic losses due to reproductive problems in Utah and southeast Idaho DHI herds. J. Dairy Sci. 70, Suppl. 1:138.
57. Lay, D. C., T. H. Friend, R. D. Randel, C. L. Bowers, K. K. Grissom, and O.C. Jenkins. 1992. Behavioral and physiological effects of freeze or hot-iron branding on crossbred cattle. J. Anim. Sci. 70:330-336.
58. Littledike, E. T., J. W. Young, and D. C. Beitz. 1991. Common metabolic diseases of cattle: Ketosis, milk fever, grass tetany, and downer cow complex. J. Dairy Sci. 64:1465-1482.
59. Maddux, J. N. 1990. Freeze branding Georgia cattle. p. 1210.00-1210.10. In Part II -- Dairy Management Manual. West. Reg. Dairy Ext. Proj.
60. Majeskie, J. L. and B. R. Eastwood. 1990. Status of United States Dairy Cattle. NCDHIP Handbook:1-14.
61. McDonald, D. 1991. Diet can control methane production. Dairy Today 7:74.
62. Mills, S. E., D. C. Beitz, and J. W. Young. 1986. Evidence for impaired metabolism in liver during induced lactation ketosis of dairy cows. J. Dairy Sci. 69:362-370.
63. Natzke, R. P. 1981. Elements of mastitis control. J. Dairy Sci. 64:1431-1442.
64. Nieuwhof, G. J., H. D. Norman, and F. N. Dickinson. 1987. Trends in herdlife of dairy cows in the United States. J. Dairy Sci. 70, Suppl. 1:152.
65. Noller, C. H. and V. F. Colenbrander. 1990. Influence of type of housing on the eating and rumination behavior of lactating dairy cattle. Purdue Univ. Report: Beef/Dairy. pp. 71-73.
66. Nott, S. B., D. E. Kauffman, and J. A. Speicher. 1981. Trends in the management of dairy farms since 1956. J. Dairy Sci. 64:1330-1343.
67. Otterby, D. E. and J. G. Lynn. 1981. Advances in nutrition and management of calves and heifers. J. Dairy Sci. 64:1365-1377.
68. Piertse, M. C., P. L. A. M. Vos, Th. A.M. Kruip, Y. A. Wurth, Th. H. van Benedon, A. H. Willemse, and M. A. M. Taverne. 1991. Transvaginal ultrasound guided follicular aspiration of bovine oocytes. Theriogenol. 35:857-861.
69. Purcell, D. 1988. Effects of four types of housing on growth and behavior of split-embryo calves. Thesis, Utah State University, Logan.
70. Reeves, P. M. and H. O. Henderson. 1963. Dairy cattle feeding and management. John Wiley and Sons, Inc., New York.
71. Robbins, J. 1987. Diet for a new America. Stillpoint Publishing, Walpole, NH.
72. Rollin, B. E. 1990. Animal welfare, animal rights, and agriculture. J. Anim. Sci. 68:3456-3461.
73. Rowan, A. N. 1988. Animal anxiety and animal suffering. Appl. Anim. Behav. Sci. 20:135-142.
74. Roy, J. H. B. 1980. The calf, 4th ed. Butterworths, London.
75. Sainsbury, D. 1986. Farm animal welfare: Cattle, pigs and poultry. Collins, London.
76. Sattler, C. G. and M. R. Detine. 1989. Trends in herd age structure and the relationships with management characteristics in Wisconsin Holstein herds. J. Dairy Sci. 72:1027-1034.
77. Sauber, C. M. 1991. Tough quality rules. Dairy Herd Management 28(6):10-12.
78. Sawyer, G. J., W. J. Fulkerson, G. B. Martin, and C. Gow. 1986. Artificial induction of lactation in cattle: Initiation of lactation and estrogen progesterone concentrations in milk. J. Dairy Sci. 69:1536-1544.
79. Scholten, B. A. 1990. Animal rights and wrongs in Europe. Hoard's Dairyman 135:190.
80. Screenan, J. M. 1988. Embryo transfer: Its uses and recent development. Vet Rec. 122:624-629.
81. Singer, P. 1990. Animal liberation. 2nd Ed. Random House Inc., New York.
82. Smith, R. 1990. Calf raisers seize special niche in California's valley of the dairyman. Feedstuffs 62:18-19.
83. Stephens, D. B. and J. N. Toner. 1975. Husbandry influences on some physiological parameters of emotional responses in calves. Appl. Anim. Ethol. 1:233-243.
84. Stevenson, J. S. and E. P. Call. 1988. Reproductive disorders in the periparturient dairy cow. J. Dairy Sci. 71:2572-2783.
85. Tarrant, P. V. 1990. Transportation of cattle by road. Appl. Anim. Beh. Sci. 28:153-170.
86. Trunkfield, H. R. and Broom, D. M. 1990. The welfare of calves during handling and transport. Appl. Anim. Behav. Sci. 28:135-152.
87. Turner, F. and J. Strek. 1981. Farm animal welfare: Some economic considerations. Int. J. Stud. Anim. Prob. 2:15-18.
88. U.S. Department of Agriculture. 1991. Milk: production, disposition and income. Da 1-2(91).
89. U.S. Department of Agriculture. 1990. Agricultural statistics. U.S. Govt. Print. Office, Washington, DC.
90. U.S. Department of Agriculture. Milk Production. 1990. Natl Agric. Stat. Service. DA 1-1 (2-90).
91. Veissier, I., P. LeNeindre, and G. Trillot. 1989. The use of circadian behavior to measure adaptation of calves to changes in their environment. Appl. Anim. Behav. Sci. 22:1-12.
92. Walton, J. S. and G. J. King. 1986. Indicators of estrus in Holstein cows housed in the stalls. J. Dairy Sci. 69:2966-2973.
93. Warnick, V. D., C. W. Arave, and C. H. Mickelsen. 1977. Effects of group, individual, and isolated rearing of calves on weight gain and behavior. J. Dairy Sci. 60:947-953.
94. Wierenga, H. K. 1991. Behaviour of Dairy Cows Under Modern Housing and Management. Thesis, Agricultural University, Wageningen, The Netherlands.
95. Wisniewski, E. W., C. W. Arave, and R. C. Lamb. 1976. Raising dairy calves in northern Utah. Utah Science 37:20-23.
96. Wynne-Tyson, J. 1979. Dietetics: Its influence on future farming patterns. In Animal Rights -- A Symposium. Centaur Press, Ltd., London.
97. Zweigbaum, W. H., M. L. McGilliard, R. E. James, and D. M. Kohl. 1989. Relationship of management and financial measures among dairy herds in Virginia. J. Dairy Sci. 72:1612-1619.
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