Selection and Management of the Boar

New Zealand Journal of Agriculture, Volume 79, Issue 3, 15 September 1949, Page 273

Selection and Management of the Boar

THE inherited qualities of growth and type place a definite limitation on what can be achieved by feeding and management in the profitable production of porkers and baconers. As the boar contributes half of the inherited make-up of all the pigs to be fattened and therefore has the widest influence over the type of fat pigs turned off, the importance of care in his selection is obvious. Proper management of the boar can influence litter results and prolong his useful life, and in this article A. Longwill, Superintendent of the Pig Industry, Department of Agriculture, Wellington, deals with the regular care and management necessary if the boar is to fulfill his importtant function in the breeding herd. .

THOUGH on an average under New Zealand conditions boars sire about 200 piglets, a boar may well sire up to 1000 pigs in his lifetime, and as each pig depends on the boar for half of its inherited characters, including type, growth-rate, and efficiency of food conversion, the need for care in the selection of the herd sire cannot be stressed too . strongly. This applies to the producer who is breeding for the weaner market as well as to the fattener. The farmer who purchases weaners or stores will gladly pay a premium for the right type of pigs which he knows grow quickly and at the same time produce a high-quality carcass.

Generally, however, home-bred pigs are the most satisfactory and the producer who breeds and fattens all his own pigs sees most clearly the value of a well-bred sire. Some boars leave progeny which, though being rapid growers, do not produce desirable carcasses; others leave progeny which have good carcass 'quality, but are too slow and expensive to grow. It certainly pays to “breed your own” if the right boar which combines the most desirable qualities can be found.

Use of Crossbred Sows

Unfortunately, some pig producers, either through carelessness or working on the principle that crossbreeding tends to give quick-growing pigs, have ended up with mongrel pigs which do not produce the best growthrate and certainly have very indifferent carcass quality. Though the use of crossbred sows can be justified for the commercial producer, it is probably best not to go beyond the first cross. There is some evidence that the first-cross sow mated to a boar of a third breed is the basis of a satisfactory breeding system. How successful it will be must, of course,

depend largely on the inherited makeup of the purebreds which have been mated to produce the commercial pigs and, most particularly, the inherent qualities of the boar. As uniformly high carcass quality under competitive conditions is the soundest safeguard for the market for pig meats, it is desirable that the boar. should be from a strain which has been proved by carcass tests to have the desirable carcass quality characters. Such qualities can be properly judged only when. a reasonable rate of growth, say, ,701 b. carcass gain per day, has been achieved and this point must be carefully watched in selection. Carcass competitions which take no heed of growth-rate are of little value in helping with the selection of the best strains. The carcass quality scheme operated by the Department of Agriculture in conjunction with district pig councils and the trade is designed to assist in this direction and much greater use should be made of & Rrppdinn Princinlpq and Selection Dreeaing Principles ana selection The pedigree breeder has undertaken a serious task and one which places upon him a real responsibility to the industry ,as a whole. The breed society lays down standards which contain about 50 points of varying significance. These standards .of excellence refer only to points which can be seen and assessed on the live pig, and, taking the utility point of viewthat pigs are bred to produce meat of the best quality as economically as possible—one is forced to the conclusion that adherence to these standards exclusively would mean the failure of the pure breeds to assist in improving the efficiency of pigs generally as producers of meat. Systems of measuring performances have played a large part in improving many breeds of domestic livestock in recent years. These are available in

the form of litter recording and carcass evaluation, coupled with growthrate recording, for pigs, and until these means are used generally by pedigree breeders selection for improved performance characters is severely limited. In selecting for the large number of desirable points sought in pedigree pigs the progress that can be made in any particular aspect is very small, By concentrating selection on the major points of efficient production and relegating to the background minor “fancy” points rapid progress could still be made. Commercial Breeding Plan T , * * P™ven ia=t that improvement . K J® a proven fact that improvement in .any Particular factor is greatly speeded up' by eliminating selection or a multiplicity of other factors. It appears therefore that , a ; national breeding plan . based on the improvement of individual breeds for specific purposes to play a predetermined part in the plan would give a more rapid improvement in economy of commercial production than anything else. Two breeds might be selected as the p are nt breeds of the commercial firstcross sow. They would be tested by litter recording for the qualities required in the sow, fecundity, mother - i n g ; and milking capacity. The firstcross commercial sow in most cases wou i d have these qualities developed even to a greater extent than the purebred strains from which she was bred v The ultimate test of the ability o f a boar to sire good sows lies in litt rpcnrf i s of a fair samnle , I ( ie “‘ ter "*L ot ? lis . daughters. Select on o boars in these breeds must be based on this principle, which is precisely that underlying the merit sire scheme in the breeding of dairy cattle.

A third breed, selected as the “sire breed” for all commercial stock, would be selected for carcass quality and economy of gain under testingstation conditions. The already-high standard available in the Large White breed, particularly in carcass quality, points to this breed as the most suitable as the sire breed. The fact that all pigs would be white skinned, forming a more uniform line and making them equally suitable as porkers or baconers, is a further argument in its favour. But selection would require to be made for resistance to sunburn and for economy of gain as well as carcass quality. The test of the ability of a boar to transmit desirable carcass y. quality characters lies in full carcass evaluation of a representative sample of his progeny produced under conditions closely similar to those of average commercial practice, together with consideration of rate of growth and economy of gain. When breeders decide to apply these tests and commercial producers are prepared to pay for the boar with a real pedigree of performance further improvement in the efficiency of per-

formance of the pig stock of this country will be possible. The soundness of the industry as a whole must benefit by the improvement of quality achieved. Selecting Boar for Commercial Herd Though the commercial producer should base his selection of a boar on information along the lines indicated above, it is obvious that at present more primitive and less satisfactory means of selection will have to suffice. He should see as many as possible of the stock bred from the same parents as the boar under offer—pigs from the same sire by different sows and also, if possible, pigs from previous litters of the same sow. The ability of parents to transmit the qualities desired in the sow, prolificacy, mothering, and milking ability, can be assessed if daughters have had litters. If no carcass grading or carcass quality scheme measurement records are available, the selection for carcass quality will have to be judged by eye.

Again, the over-all assessment of the strain of stock will be much more valuable than basing judgment on the single animal. The judgment of a reasonable number of similarly-bred pigs at about the baconer stage at 6 months of age will provide the best basis under these conditions. However, the person making the selection must have a sound idea of the indications of length and other essential quality characters as well as of sound constitution. It is not sufficient to purchase a pedigree boar simply because it is a registered • animal or bred from registered parents. Without the backing of progeny tests at each stage in the pedigree the paper pedigree is of limited value. Development of the Boar Any young boar which shows any definite weaknesses while on the sow should be castrated as early as possible, and a close watch should be

kept throughout development and further culling carried out as necessary. Though the young boar should always be well fed, he should never be forced to produce too much weight at an early age. Adequate proteinrich food for body . building, with ample exercise and grazing, should be allowed throughout the growing stage. At 4 months, if not earlier, the litter should be divided, the young boars thereafter being kept in a pen to themselves. If feeding and management have been satisfactory, the boar should reach 2001 b. liveweight in 6 months. At this stage occurs the best opportunity to select a boar for future use; checking up on this preliminary selection must, however, await the progeny test.

Soon after this stage a young boar may be used for an occasional service, but, unless he is well grown, it is best to restrict such services very

severely until he is » or y months old. Even then services should be restricted to one per day and not more than one sow (two services) in a week. The sow should not be allowed to run with the boar during the heat period. If one boar only is kept, it is worth while having one or two in-pig sows running with him for company. In bigger piggeries it is satisfactory to run two or more boars together, provided the practice is - regularly followed and the boars are detusked. Under these conditions a service pen out of sight of the boar paddock is required. It is wise when putting a new boar in with others already in the boar paddock to oil all boars before mixing, to see that tusks are rendered harmless, and then to watch to see that the new boar is not knocked . about by the others. Feeding Where skimmed milk is the basic food ample protein will be available, but a little cereal meal supplement at the rate of lib. to 5 or 6 gallons of milk is warranted even at present high meal prices of £2O to £22 per ton

for barley meal in the main pigproducing districts. Five small feeds a day for young pigs are desirable on bulky dairy by-products to get optimum growth and yet avoid a potbellied appearance. This applies with even greater force to whey feeding. Whey must be supplemented with meat meal at the rate of Jib. per pig per day to secure optimum body . growth. The animal being reared for breeding purposes will benefit from a slightly rate of protein feeding than this and when sufficient meat meal is available it can be allowed lib. per day from 6 months of age until maturity. During this later stage a greater proportion of the total food required can be obtained from grazing. At a year old a boar can obtain about half the food required from grass if this is of a highly-nutritious character. Hand feeding at this stage should comprise 3 gallons of skimmed milk and lib. of cereal meal or 5 gallons of whey and lib. of meat meal. When grazing is deficient the ration must be built up with home-grown crops or bought meals on a food unit basis, and consideration given, particularly in winter, when the milk proteins are not available, to the necessity to keep up the protein level of feeding by means of meat meal, pea meal, or other satisfactory protein-rich feeds. . A good guide to feeding is to aim at giving by hand 1 food unit per 1001 b. liveweight when good grazing is available and at least double this when no grazing value ,is being obtained. Home-grown crops, of course, form the cheapest basis of providing the necessary bulk, but with these up to lib. of meat meal and cereal meal, according to price and the condition the animal is maintaining, should be used. When the pig is mature f food unit per 1001 b. liveweight, in addition to

grazing, should suffice. However, in these recommendations, as in all feeding guides, allowance has to be made for me individuality of the animal. Thus it is left to the art of the feeder to ensure good growth and development, to give full expression to the inherent constitution of the animal, and on the other hand to ensure that feeding is not so forced or unbalanced as to produce overfatness, a potbellied appearance, or weakened legs or feet. Detusking A surgical operation for removal of the tusks at about 1 year old may be performed, but this is the more expensive, if more permanent, way of detusking, as it requires the administration of an anaesthetic and the services of a veterinarian. A simpler and quite effective way of detusking is to rope the boar securely to a post and sever the tusks by means of bolt-cutters, a wood chisel used against a block of wood placed through the mouth to form a resistance on the inside edge of the tusk, or a hacksaw. Where the boar runs with the dry sows it is particularly necessary to de tusk, though it Is an insurance against accidents at all times. When a boar feeds with sows the .sows are frequently ripped by his tusks and occasionally this may have serious consequences with in-pig sows. Service Management The act of mating in the pig normally extends over about 10 minutes and no disturbance should be permitted during mating. If more than one boar is kept, the boar required should be taken out into a separate service pen or paddock, and the sow to be mated, after she has been showing signs of heat for 24 hours or so, should be turned in with him and left

Until it is certain that a satisfactory service has taken place. After a further 24 hours a second service should be given. Where only one boar is kept it is satisfactory, of course, to turn in the sow at the appropriate times to the boar pen. Sue should be taken out after each service, and if the practice is to run the dry sows with the boar, finally turned out in this paddock only after the heat period has passed.

In general, two services at 24-hour intervals, the first at 24 to 36 hours after the commencement of heat, give the best results measured by fertilisation of the greatest number of eggs. However, if the breeding season is concentrated so that a number of sows require service from the same boar in a limited period, say, more than three sows to be mated to the same boar in a week, it is preferable to limit services to one per sow. This should then be delayed until the sow has been on heat at least 36 hours.

Service Crates

Though they are not commonly used in New Zealand except in breeders' establishments, service crates enable services to be better controlled and permit the use of aged boars on young sows and vice versa.

“Commercial Glasshouse Construction in Canterbury”

IN the article "Commercial Glasshouse Construction in Canterbury,” which appeared on page 597 of the June issue an error occurred in the tables on page 599, which set out the number of sash bars required for three differentsized glasshouses. In every case the number of sash bars given in the tables is one short of the correct number. The correct figures are set out below. I OOft. x 30ft. Glasshouse 16in. glass: 68 sash bars + 2 end bars = 99ft. 6|in. long, or 69 sash bars + 2 end bars = 100 ft. lljin. long. 20 sash bars + 2 corner posts —30 ft. 6Jin. wide. 18in. glass: 61 sash bars + 2 end bars = 99ft. 9Jin. long, or 62 sash bars + 2 end bars = 101 ft. 4fin. long. 18 sash bars + 2 corner posts = 30ft. 9fin. wide. 20in. glass: 55 sash bars + 2 end bars = 99ft. 6in. long, or 56 sash bars + 2 end bars = 101 ft. 3|in. long. 16 sash bars + 2 corner posts —30 ft. sJin. wide. I OOft. x 15ft. Glasshouse The numbers of sash bars and the lengths of the houses are the same as for 100 ft. x 30ft. houses, but the exact widths are: 16in. glass: 10 sash bars + 2 corner posts = 16ft. IJin., or 9 sash bars + 2 corner posts = 14ft. BJin. 18in. glass: 9 sash bars + 2 corner posts = 16ft. 4Jin., or 8 sash bars + 2 corner posts = 14ft. 9tin. 20in. glass: 8 sash bars + 2 corner posts = 16ft. 3Jin., or 7 sash bars + 2 corner posts = 14ft. 6in. 50ft. x 15ft. Glasshouse Widths are the same as for 100 ft. x 15ft. houses, and the exact lengths and numbers of sash bars required are: 16in. glass: 34 sash bars + 2 end bars = 50ft. 7|in. 18in. glass: 30 sash bars + -2' end bars = 50ft. Olin. 20in. glass: 27 sash bars + '2 end bars 49ft. Ilin.

DAIRY PRODUCE GRADED FOR EXPORT

THE following figures showing quantities of dairy produce graded for export during July and for the 12 months ended July 31, 1949, with comparative figures for the same month and 12-monthly period of last year, have been compiled by the Dairy Division of the Department of Agriculture from figures supplied by divisional officers at the various grading ports : BUTTER— Tons Tons Percentage Total in store Period Creamery Whey Total inc. or dec. at end of mth. July, 1949 1,494 8 1,502 +35.927 7,220 July, 1948 1,100 5 1,105 5,647 Increase or decrease .. .. +394 +3 +397 +1,573 For 12 months ended 31/7/49 143,676 2,641 146,317 +ll.OBl For 12 months ended 31/7/48 129,382 2,339 131,721 Increase or decrease .. .. +14,294 +302 +14,596 CHEESE — Tons Tons Percentage Total in store Period White Coloured Total inc. or dec. at end of mth. July, 1949 .. .. .. 201 7 208 —11.489 5,457 July, 1948 235 235 1,421 Increase or decrease .. .. —34 +7 —27 +4,036 For 12 months ended 31/7/49 89,639 5,170 94,809 +14.408 For 12 months ended 31/7/48 82,869 82,869 Increase or decrease .. .. +6,770 +5,170 +11,940 If these figures are converted into butterfat equivalent, there is an increase of 11.826 per cent, in butterfat graded for the 12 months as compared with the corresponding period of the preceding season. It should be noted that the above figures refer only to butter and cheese graded for export, and that owing to diversions which may take place from time to time, they are not necessarily a true indication of production trends.