Jersey cattle are believed to have been first brought to Denmark between 1896 and 1909. During that period 5,303 animals were imported. The first twelve came from Sweden and the rest from the island of Jersey.
The only cattle imported in the long period which has since elapsed were a few bulls brought from Jersey after the Second World War.
The rate of increase of Jersey cattle is illustrated by the following table:
The yields of some 60 per cent of all Jersey cows in Denmark are recorded all the year round. Trends are shown in the following table which gives average yields of all recorded Jersey cows.
The rapid increase in numbers of Jersey cattle has been accompanied by a marked rise in milk yields and especially in butterfat content.
In the first two decades after the early importations the rate of numerical progress was moderate, but in the last two the number of Jersey cows has increased tenfold.
Mr. Jørgen Larsen was the first to bring Jersey cattle to Denmark and was responsible for all early importations. Jørgen Larsen created Denmark's northermost estate by drying out a lake and afforesting sandy areas. His transformation of water and sand into fertile fields and green woods won him great esteem, which was of considerable help in his introduction of the new breed.
Mr. Larsen became a well-known man on the island of Jersey during the years when he imported Jersey cattle. He did not buy expensive show-animals nor invariably the most well-shaped animals; he bought cheap. The Jersey Island farmers said that he bought the "rubbish". All the imported animals were free from tuberculosis, but many were infected in Danish cowhouses and soon succumbed to the disease.
Consequently Jersey cattle gained a reputation for delicacy which impeded the progress of the breed for many years. But breeders of Jerseys were among the first to take up the struggle against bovine tuberculosis. This battle has now been won: bovine tuberculosis has been completely eradicated from Denmark.
The rapid growth of Jersey cattle in Denmark is due to economic considerations. Milk-production is Denmark's biggest industry. About 70 per cent of the national output is made into butter, nearly 10 per cent into cheese, a small proportion is sold as condensed milk and the remainder as liquid milk. Since buttermaking is thus by far the most important product of milk, naturally Danish co-operative dairies pay for milk supplied by farmers according to its butterfat content; liquid milk, too, is paid for in proportion to the amout of fat which it contains. Hence Danish dairy-farmers are vey much interested in the butterfat content of their milk and always record the yields of cows in terms of butter.
Experiments have shown that for at given quantity of food, more butterfat is produced from rich than from poor milk; numerous milk tests have also shown that the protein content of milk increases with its butterfat percentage, while the content of lactic sugar decreases slightly. Consequently the relative cost of production is lowest, for both butter and cheese, when the milk is rich. As butterfat and protein are the most nutritive and valuable components of milk, the best economy in the supply of liquid milk for human consumption, too, is achieved with rich milk. Since the Jersey cow, being comparatively small, needs only modest quantities of food for maintenance, she is our most economical dairy cow. In recent years the Danish Jersey cow has yielded about 20 kilograms of butterfat more than the average of all other breeds in Denmark, and the foo-consumption of
Jersey cows per kilogram of butterfat produced is three to four feed units lower. A Scandinavian feed-unit is equivalent in nutritive value to one kilogram of barley.
Jersey breeding is controlled by the Danish Jersey Cattle Society, founded in 1902 by Jørgen Larsen,
who was its President until 1927. He was succeeded by J. Kr. Madsen, who in turn was followed in 1942 by H. Clausager. Mr. Clausager remained President until 1948.
Since the subscription payable by members is kept at a modest figure, a comparatively large number of Danish Jersey breeders are members of the Society, including many smallholders.
Jersey cow milk yields are recorded by Milk Recording Associations embracing all breeds. Output is recorded in terms of annual yields from the 1st of October to the 30th of September of the following year. The recording year comprises the dry period. All breeding animals are registered by the Milk Recording Associations under the supervision of an agricultural adviser. No breeding animal can be entered in a Herd Book without having been registered and the cows must have been recorded for milk yield and fatpercentage.
The Danish Jersey Herd Book is published by the Danish Jersey Cattle Society in colloboration with the Danish Farmers' Union. The first volume was published in 1925.
The Herd Book for bulls comprises two categories: (1) Herd Book for Bulls; (2) Elite Herd Book for Bulls.
Before a bull can be entered in the Herd Book it must be registered and have been approved as a typical specimen and of good conformation. Both its parents must be in the Herd Book, or its dam and paternal granddam must be in the Elite Herd Book.
Only proven sires can be entered in the Elite Herd Book.
A dam-daughter comparison of not less than five daughters must show progress from dams to daughters, and at least three daughters must be eligible for entry in the Elite Herd Book.
Eligibility of a cow for entry in the Elite Herd Book for cows is conditional upon her having produced not less than 900 lb of butterfat in two consecutive yeears. The fat percentage must not bee less than 6; if it is lower, 20 lb more butterfat is required for each 0-1 per cent of the deficiency. If the cow weighs more than 491 lb (450 kg.) the qualifying yield is raised by about 0-88 lb of butterfat for each kilogram over-weight (the equivalent of one kilogram of butter for each kilogram over-weight). The live weight of a cow is calculated from the heart girth.
One volume of the Herd Book is published every year. The following tables show trends in the yields of Herd Book cows. Table III gives the average yields of Herd Book cows in all years, while Table IV shows averages for the two best consecutive years.
The tables show conclusively that Danish Jersey cows prove their worth by yielding milk with a high content of butterfat. In order to select the best breeding bulls, progeny tests are made at the earliest stage. When a bull has at least five daughters which have yielded milk for 100 days, the daughters are compared with their mothers for the first 100 days after the first calving. The preliminary comparison affords a valauble indication of the ability of the bulls to pass on productive capacity to their offspring.
When the daughters of the bull have completed a lactation period a new examination is made in which the yields of the daughters are compared with those of their mothers in the corresponding llactation periods. Both examinations must comprise all the daughters of the bull.
About 60 per cent of all cows in Denmark are inseminated artificially. It is therefore essential that the best bulls should be selected at an early age and be utilized for insemination as much as possible.
Danish Jersey breeders have always tried to breed high-yielding remunerative cows and have paid less attention to details of conformation. At cattle shows prizes are awarded to cows on the basis of their yields og to bulls according to their presumed abillity to transmit productive capacity to their progeny.
No. 9 Kaerbyholm, Elite Herd Book No 1035
Average of 4 years 1942-46 4891 kg milk 6,47 per cent butterfat = 360 kilogram of butter
Points awarded for the productive capacity of cows are adjusted according to size. For each centimetre of heart-girth exceeding 170 cm. (equal to about 410 kgs. weight) 1-7 kg. of butterfat (equal to 2 kg butter) is deducted to allow the greater quantity of food which the animal consumes. Conversely, cows measuring less than 160 cms. (equal to about 345 kg weight) are credited with 1-7 kg of butterfat in recognition of their low cost of maintenance. After these adjustsments, points are awarded for yield of butter and butterfat percentage.
Our feeding experiments have shown that one feed unit is saved for each kilogram of butter produced every time a cow's annual yield of butterfat increases by 50 kg and eveyr time the fat percentage increases by one. On the basis of these criteria, points are awarded so as to be related to economy of production. The prizes are thus awarded with a view to singling out the most efficient dairy cows.
In addition to the prizes for yields the animals are classified in such a way that the finest and most typical with well-shaped udders are classified as Type I; larger and coarser animals are classified as Type II; while nontypical, ungainly animals are assigned to Type III.
A special series of progeny tests has been introduced in recent years by the National Research Institute on Animal Husbandry. Before their first calving twenty daughters of each bull are taken to an experimental farm and given uniform feed and care while their yields are recorded for 304 days after the first calving. The special progeny tests have so far been completed for only four Jersey bulls, but several groups of daughters from Jersey bulls are to be tested in this way.
The following table shows the average results of the tests completed for each breed.
These results may not give a final and complete picture of the yielding capacity of the different breeds, but they do show show that the Jersey maintains its superiority in butterfat yields. The decisive factor, however, is the low food consumption of Jersey cows. A calculation will show that Jersey cows have turned out substantially greater values per feed unit expended than have the other breeds. Each year since 1922 the Danish Jersey Cattle Society has awarded gold, silver, and bronze medals to the Herd-Book recorded Jersey cows, which, for a maximum lactation period of 365 days, produced the highest yields in butterfat. Among the highest yields are that of the cow Nanette (Elite Herd Book No.
232). IN 1929 she produced 12,819 lb. milk with 8,89 per cent fat and 1,140 lb. butterfat. The Danish record for butterfat yield was set in 1952 by Cow No. I (Elite Herd Book, No. 1870). She produced 14,709 lb. milk with 7,89 per cent fat and 1,161 lb. butterfat.
The Danish Jersey Cattle Society has also awarded silver cups each year to the Jersey cow that has produced the biggest quantity of butterfat in her lifetime. The record for lifetime yield was set by a cow named Indslev (Elite Herd Book No 425), which in the course of fifteen years produced 153,395 lb. milk with 5,57 per cent fat and 8,697 lb. butterfat. Several of her sons have been used extensively for breeding and all have proved excellent animals.
Since productive capacity has always been the first consideration in selecting breeding animals, the efficiency of Danish Jersey cattle to transmit butteryielding ability from parents to offspring has been made comparatively uniform and certain.
The bull Bravo has been of special importance in Danish breeding.
Bravo was born on the island of Jersey on the 3rd of March 1895, and registered in the Island Herd Book as No. 2267 (Highly Commended). He was imported into Denmark and registered in the Danish Herd Book as No 1. He was used in Mr. Larsen's herd and many of his descendants have been used as stud bulls in Denmark.
The Jersey herd "Kaerbyholm" established 1908, owned by Hans Anton Hansen and later his sons. The average annual herd yield 1908-1961 Line-breeding in the herd of Mr. H.A. Hansen, Kaer- byholm, was based on a son of Bravo. From Mr.Hansen's herd numerous breeding animals went to Danish Jersey herds, and most of them proved excellent sires.
The latest scion of this line of bulls is Lasse (Danish Herd Book No. 932), born on the 28th of March 1946. A test group of daughters of Lasse is completing its recording year (September 1953) at the progeny-testing station with the highest butterfat yield of all progeny-tested groups.
Another descendants of Bravo is the cow Nybøllegaard No 39 (Danish Herd Book No 230). Her yield averaged 10,610 lb milk with 5,85 per cent fat over twelve years.
Several sons of Nybøllegaard 39 and of the daughter No 12 (Danish Herd Book No 410) have been used extensively for stud, and all their descendants have been very high-yielding animals.
Another cow, Ketty Black (Danish Herd Book No 489), also descends from Bravo. Her average yield for six years was 7,950 lb milk with 7,91 per cent fat. She became the ancestress of a line of bulls called Oddenbo, which has provided excellent breeding animals.
There is still another line of bulls, the Indslev Ellekaer (Danish Herd Book No 393), which has been very prominent in recent years. The ancestress of Indslev Ellekaer was cow No 7, Ellekae r (Danish Herd Book No 335), whose average yield for thirteen years was 8,798 lb milk with 5,69 per cent fat. The sons of the previously-mentioned cow No 25, Indslev, and most of these sons are therefore named Ellekaer.These families form the basis of the Danish Jersey cattle of today.
As long as the production of butter and cheese remains a vital factor in Danish economy, Jersey cattle are sure to hold an important place in Danish agriculture. And as long as that holds good Jersey breeders will press on tirelessly to develop animals giving the best possible economic return, repaying each unit of food with the largest possible quantities of the most valuable components of milk: butterfat and casein. The ultimate goal is the small, fine cow which breeds true to type, has a well-shaped and
well-attached udder and gives a big milk-yield containing a high percentage of butterfat.