WO2000016788A1

WO2000016788A1 - Method for successful early weaning of very young swine

Info

Publication number: WO2000016788A1
Application number: PCT/US1999/021855
Authority: WO
Inventors: Robin Anderson; John R. Deloach; David J. Nisbet; Trevor Tomkins; Larry H. Stanker
Original assignee: Ms Bioscience
Priority date: 1998-09-21
Filing date: 1999-09-21
Publication date: 2000-03-30
Also published as: AU6396199A

Abstract

A method is disclosed for enhancing the survivability of very young piglets. The method includes dosing a piglet with a competitive exclusion product, weaning the piglet as soon as the piglet has received sufficient colostrum from a sow to establish maternal antibodies in the piglet, and feeding the piglet with a liquid feed diet until the piglet is large enough to be transferred to a feeder diet.

Description

METHOD FOR SUCCESSFUL EARLY WEANING OF VERY YOUNG SWINE

FIELD OF THE INVENTION The present invention relates to pork production, and in particular relates to a method of increasing the survival rate of pigs by successful early weaning of very young piglets from their sows.

BACKGROUND OF THE INVENTION Pork production has increased dramatically in the United States and other countries in recent years. In particular, the growth in the pork industry has been accompanied by an increase in the number of production facilities which handle a large number of pigs in a controlled setting. In a general scheme, pigs are born to sows in litters of between about 9 and 13 pigs per sow. The sows and their litters are typically kept in an enclosure known as a farrowing crate while the pigs in the litter are being nursed. When the pigs are old enough to be weaned (typically at a weight of about 15 pounds), they are moved to another area of the facility referred to as the "feeder floor," at which they are started on solid food until they reach a weight of about fifty (50) pounds. At that point, their diet is changed somewhat and they are either physically and functionally transferred to the "grower" portion of the facility where they are fed a growth diet until they are a proper size for slaughter and meat production. As noted above, these steps now typically take place in large managed facilities. The nature of these are such that the farrowing crates are designed to hold an average litter of nine pigs along with their sow. Accordingly, if a litter is larger than nine pigs, the weaker members are not expected to be able to compete for nursing time at the sow and are typically removed from the litter and left to expire. In general terms, weak piglets are those weighing less than one kilogram (1 kg) at birth, and tend to comprise 10-20% of each litter.

Removal from the litter, of course, requires that the pigs, which already tend to be the weaker members of the litter, be fed with some nutrition source other than the sow's milk. Because of the size of typical farrowing operations, any such replacement nutrition is usually in the form of a liquid diet, and is provided through a relatively complex liquid feeding system that concurrently handles a large number of pigs. As a result, the liquid feed systems tend to be susceptible to contamination with bacteria that may or may not affect full grown pigs or healthier members of the litter, but which tend to greatly, and negatively, affect weaker pigs that have been removed from their sow. Furthermore, weaning is stressful on all piglets at all ages, and thus is particularly stressful for very young piglets that are already the weaker members of their litters. Indeed, some studies indicate that piglets experience more than 20% mortality even before weaning (e.g., U.S. patent No. 5,073,367 at column 1, lines 15- 30). Weaned piglets tend to have a 10% mortality rate and 30% of weaned piglets experience significant weight loss that in turn requires that they be given additional feed, additional growing time, or both. One particularly problematic bacteria is part of the Salmonella group of bacteria, and in particular is the Salmonella Choleraesuis bacteria. This particular bacteria tends to cause septicemic diseases in swine, and its related bacteria such as Salmonella Typhinurium cause enteritis. Thus, the presence of Salmonella bacteria poses at least two problems. First, under some circumstances, the Salmonella bacteria may survive throughout the chain of meat production, distribution, and marketing, and thus pose a health risk to ultimate consumers. Second, the Salmonella bacteria can cause an increased mortality rate at the swine facility itself. Accordingly, minimizing or eliminating Salmonella remains an important goal in the swine, meat, and food industries. In addition to these factors, pork production in certain regions of the United

States is being legislatively curtailed, or at least prevented from expansion, because of environmental concerns. Indeed, at the time of this application, certain states have established moratoriums against any increase in hog facility sizes. Accordingly, given these limitations against expanding their production facilities, pork producers must increase production from existing facilities in order to increase overall pork production. One method of increasing the production would be to increase the survivability of pigs in larger than average litters. As noted above, however, in larger litters, a number of the pigs will have a lessened ability to compete for maternal nourishment; i.e. small birth weight piglets. Accordingly, rearing the weaker piglets in nurseries, beginning as early as 24 hours of age, is one possible strategy for insuring that these piglets have an appropriate opportunity for nourishment. At this very young age, however, the immaturity of the gut flora tends to predispose these piglets to certain enteric and systemic diseases such as those cause by the Salmonella Choleraesuis bacteria noted above.

Accordingly, a need exists for protecting early weaned piglets from the typical diseases that would otherwise increase their mortality weight. OBJECT AND SUMMARY OF THE INVENTION

Therefore, it is an object of the present invention to provide a technique for weaning very young pigs to increase the productivity of swine operations by reducing the otherwise expected mortality in such young pigs.

The invention meets this objection with a method of enhancing the survivability of very young pigs (piglets) that comprises dosing a piglet with a competitive exclusion product, weaning the piglet as soon as the piglet has received sufficient colustrum from a sow to establish maternal antibodies in the piglet; and feeding the piglet with a liquid weaning formula until the piglet is large enough to be transferred to a feeder diet. The foregoing and other objects and advantages of the invention and the manner in which the same are accomplished will become clearer based on the following detailed description.

DETAILED DESCRIPTION The present invention is a method of enhancing the survivability of very young pigs (piglets) comprising the steps of dosing a piglet with a competitive exclusion product, weaning the piglet as soon as the piglet has received sufficient colostrum from a sow to establish material antibodies in the piglet, and then feeding the piglet with a milk replacer until the piglet is large enough to be transferred to a feeder diet. In preferred embodiments, the competitive exclusion product is one that is effective against Salmonella bacteria, and in the most preferred embodiments is effective against Salmonella Choleraesuis bacteria. In preferred embodiments, the competitive exclusion culture is one developed by the USDA in conjunction with MS Bioscience, Inc., and is referred to as pCFl or pCF3. A full description of pCFl and pCF3 is set forth in co-pending U.S. Application Ser. No. 08/949,348, filed October 14, 1997, for "Competitive Exclusion Culture for Swine," the contents of which are incorporated entirely herein by reference. As set forth therein the composition comprises populations of substantially biologically pure bacteria, with the bacteria comprising substantially all oϊ Enter ococcus faecalis, Streptococcus bovis, Clostridium clostridiforme, Clostridium symbiosum, Clostridium ramosum, Bacteroides fragilis, Bacteroides distasonis, Bacteroides vulgatus, Bacteroides thetaiotamicron, and Bacteroides caccae. As generally well understood by those familiar with disease prevention in animals, a competitive exclusion product is one that prevents infectious diseases rather than treating them. As the name "competitive exclusion" indicates, the product provides the digestive tract of an animal (in this case the pig) with cultures that predominate to an extent that prevents the survival of detrimental cultures such as the Salmonella bacteria. In this regard, competitive exclusion products, and competitive exclusion treatments, differ from the use of vaccines or antibiotics. As well understood in these arts, vaccines are used to create antibodies that protect against later viral infections, while antibiotics are usually pharmaceutical compositions that attack detrimental bacteria that are already present. Competitive exclusion products are also referred to as "probiotics."

Although the phrase "early weaning" has been used in prior techniques to refer to piglets that are weaned at the age of between 14 and 21 days (as opposed to a "normal" weaning period of about a month), the method herein comprises weaning very young piglets; preferably those from birth to about 48 hours old. To date, and without wishing to be bound by any particular theories, it appears that the best results may be obtained when the piglets are allowed to nurse from the sow for up to 48 hours and thereby take up an appropriate amount of maternal antibodies. Although later weaning could theoretically give the piglet the chance to obtain more maternal antibodies, in a large litter, the smaller and weaker members will become progressively unable to compete successfully for food from the sow.

Additionally, because competitive exclusion cultures must operate within the digestive tract of the animal, it must be provided to the animal in some fashion that moves it to the digestive tract very quickly. Presently, the preferred technique for very young piglets is oral gavage. The step is referred to using the term "dosing" because of its involuntary nature, as opposed to "feeding" which the piglet is expected to perform by instinct. Following oral gavage and weaning, the piglets are then transferred to a liquid feed (liquid weaning) diet, which in preferred embodiments comprises a milk replacer. Such diets are generally well known and well understood in the animal feed arts, with a typical liquid weaning formula having the analysis set forth in Table 1 : Table 1 - Typical Liquid Weaning Formulas

A preferred milk replacer composition is available under the LIQUI-WEAN™ designation from Milk Specialties Company of Dundee, Illinois. As noted above, appropriate liquid diets for piglets (and other animals) are generally well understood and similar milk replacement products are described, for example, in U.S. Patent No. 4,083,960 at column 2, starting at line 47, or in U.S. Patent No. 5,192,804 at column 4 starting at line 11. As set forth therein, an appropriate milk replacer should include nutritional products that have a composition substantially similar to those derived from milk. Appropriate replacers can include soy protein concentrates, soy isolates, and plasma protein, as well as amino acids, other food meals, trace minerals, vitamins, antibacterials, and antibiotics as may be desired or necessary. Because these milk replacers are generally well understood in the art, they can be formulated as necessary or desired without undue experimentation. In most cases, the milk replacer is a dry product containing milk proteins and the other items noted above in a form that can be easily mixed with water to form a liquid feed.

The method of the invention is perhaps most advantageous when used in conjunction with swine production facilities that include a plurality — indeed a very large number — of sows and litters. As noted above, these large-scale hog production facilities have greatly increased in size and number in recent years, but for a number of reasons, further expansion of the overall size of the facilities may be limited in the future.

A typical facility contains a number of farrowing houses that incorporate a large plurality of farrowing crates that can hold the large numbers of sows and litters that are being raised in the facility. Some exemplary descriptions are set forth in U.S. Patent Nos. 4,252,082; 4,254,737; 4,256,057; and 4,348,987. These particular patents deal with farrowing crates and flooring for farrowing houses, but give a good general background of the nature of these facilities. These are of course exemplary rather than limiting descriptions of such facilities and other sources could be cited to illustrate the same types of facilities.

Accordingly, when used in conjunction with such facilities, the method can comprise identifying the litters in the farrowing facility that have more than a predetermined number of piglets. The predetermined number is usually nine (9) piglets because of the size, arrangement, and expectations for litter size in such facilities. It will be understood, however, that although nine is the most common litter size, the invention is not limited to litters of more than nine pigs nor is it limited to organizing litters into sets of nine piglets.

After identifying litters that are larger than the predetermined number, piglets are then removed from each litter to reduce each litter in the farrowing facility to the predetermined number (e.g., nine) piglets. The piglets are dosed with a competitive exclusion product, and the removed piglets are fed with a milk replacer until they are large enough to be transferred to a feeder diet.

As used herein, the terms "feeder" and "grower" refer to pigs of certain sizes and more properly reflect the diets given to the pigs at certain ages. Stated somewhat differently, the growth cycle of the pigs can be enhanced by weaning them at the proper time, giving them a certain solid diet referred to as a "feeder" diet in the next phase of their growth (hence the pigs are referred to as "feeder" pigs) and thereafter transferring the pigs to a somewhat different solid diet on which they grow to maturity (hence the name "grower" diet and pigs). In the preferred embodiment of the method, the competitive exclusion product noted above is fed (dosed) to all of the piglets shortly after birth, and preferably within 4 hours after birth by oral gavage. The piglets to be removed are then identified and removed at about 48 hours after birth in order to give them an opportunity to take up maternal antibodies as set forth above.

In preferred embodiments, all of the piglets are fed the competitive exclusion product shortly after birth. This provides the simplest technique for making sure that the removed piglets are treated, and also offers some protection to all of the piglets, whether or not removed.

It will nevertheless be understood, however, that the dosing with the competitive exclusion product could be limited to only the removed piglets, provided they received it early enough for it to be effective. In the same manner, piglets in each litter could be identified or even selected as removal candidates shortly after birth, and the feeding f the competitive exclusion could be limited to these candidates. The candidates so selected are then specifically removed from the litter. In either case, the selected candidates can be marked or identified in any appropriate manner known in this art, provided that the identification step does not otherwise interfere with the method of the invention.

Several trials of the technique were carried out with the following results:

EXPERIMENTAL

Piglets from two sows were treated at birth (via oral gavage) with 5 milliliters (ml) of a porcine derived competitive exclusion culture and piglets from two other sows served untreated controls. The competitive exclusion culture (designated as pCFl as noted above) was propagated from cecal contents of a healthy adult pig and was maintained in steady state via continuos flow culture methodology. At 48 hours of age, the piglets were removed from their sows and placed in a nursery where they were provided ad libutum access to liquid milk replacer. Just prior to placement in the nursery, the piglets were challenged with approximately 10⁵ colony forming units of a novobiocin and nalidixic acid resistant strain of Salmonella Choleraesuis. Specimens collected from some of the piglets at necropsy were cultured qualitatively for S. choleraesuis via preenrichment in GN-Hajna, further enrichment in Rappaport- Vassiliadis broth and selective differentiation on Brilliant Green Agar containing 25 micrograms (μg) novobiocin per milliliter and 20 μg nalidixic acid per milliliter. In the first experiment, mortality among the pCFl treated litter (n=5) and untreated litter (n=7) was 20 and 57%, respectively, by seven days post challenge. At this time the surviving piglets, which showed no ill effects, were euthanized and necropsied for collection of tonsils, ileocolic lymph nodes and cecal contents. Upon bacteriological cultivation of these samples, S. choleraesuis were recovered from some but not all of the nonsickened piglets (2 of 4 pCFl treated; 1 of 3 untreated). In the second experiment, 100% (10 of 10) of the control piglets succumbed by 4 days post challenge whereas only 40% (2 of 5) of the pCFl treated piglets had died. These observations demonstrate that administration of a porcine derived competitive exclusion culture (pCFl) provides protection to young pigs which may make nursery rearing of very young pig a feasible way to increase productivity.

In the specification, there have been disclosed typical embodiments of the invention, and, although specific terms have been employed, they have been used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being set forth in the following claims.

Claims

CLAIMS:

1. A method of enhancing the survivability of piglets comprising: dosing a piglet with a competitive exclusion product; weaning the piglet as soon as the piglet has received sufficient colostrum from a sow to establish maternal antibodies in the piglet; and feeding the piglet with a liquid feed diet until the piglet is large enough to be transferred to a feeder diet.

2. A method according to Claim 1 wherein the step of feeding the liquid feed diet comprises feeding a milk replacer.

3. A method according to Claim 2 wherein the milk replacer comprises dry milk proteins that can be mixed with water to form a liquid feed.

4. A method according to Claim 1 wherein the step of dosing with the competitive exclusion product comprises dosing with a competitive exclusion product that is effective against Salmonella bacteria.

5. A method according to Claim 4 comprising dosing with a competitive exclusion product that is effective against Salmonella Choleraesuis bacteria.

6. A method according to Claim 1 wherein the step of dosing with the competitive exclusion product comprises feeding the piglet within four hours after birth.

7. A method according to Claim 1 wherein the step of dosing with the competitive exclusion product comprises feeding the piglet via oral gavage.

8. A method according to Claim 1 wherein the step of weaning the piglet comprises weaning the piglet within two days of birth.

9. A method of increasing swine production comprising: identifying litters that have more than a predetermined number of piglets; removing piglets from each litter to reduce each litter to the predetermined number of piglets; dosing the piglets with a competitive exclusion product; and feeding the removed piglets with a liquid feed diet until the piglet is large enough to be transferred to a feeder diet.

10. A method according to Claim 9 comprising dosing all of the piglets with a competitive exclusion product shortly after birth.

11. A method according to Claim 9 wherein the step of feeding the liquid feed diet comprises feeding a milk replacer.

12. A method according to Claim 11 comprising feeding with a milk replacer that includes dry milk proteins that can be mixed with water to form a liquid feed.

13. A method according to Claim 9 comprising dosing the piglers with the competitive exclusion product within 4 hours after birth, and removing the piglets at about 48 hours after birth.

14. A method according to Claim 9 comprising dosing with a competitive exclusion product that is effective against salmonella choleraesuis bacteria.

15. A method according to Claim 9 wherein the step of dosing with the competitive exclusion product comprises feeding the piglet via oral gavage.

16. A method according to Claim 9 comprising: identifying a selected number of piglets in each litter that is less than the entire litter; dosing the selected piglets with the competitive exclusion product; thereafter removing the identified selected piglets from the litter; and feeding the milk replacer to the identified selected piglets.

17. A method according to Claim 16 comprising removing the identified selected piglets from the litter after a predetermined period of nursing at their sow.

18. A method of increasing swine production in facilities with a plurality of sows and litters comprising: identifying litters in a farrowing facility that have more than a predetermined number of piglets; removing piglets from each litter to reduce each litter in the farrowing facility to the predetermined number of piglets; dosing the piglets with a competitive exclusion product; and feeding the removed piglets with a milk replacer until the piglet is large enough to be transferred to a feeder diet.

19. A method according to Claim 18 comprising dosing all of the piglets with a competitive exclusion product shortly after birth.

20. A method according to Claim 18 comprising dosing the piglets with the competitive exclusion product within 4 hours after birth, and removing the piglets at about 48 hours after birth.

21. A method according to Claim 18 comprising dosing with a competitive exclusion product that is effective against salmonella choleraesuis bacteria.

22. A method according to Claim 18 wherein the step of dosing with the competitive exclusion product comprises feeding the piglet via oral gavage.

23. A method according to Claim 18 comprising feeding with a milk replacer that includes dry milk proteins that can be mixed with water to form a liquid feed.

: 24. A method according to Claim 18 and further comprising: transferring the piglets to a feeder diet; feeding the piglets with a feeder diet until they can be transferred to a grower diet; and transferring the piglets to a grower diet.

25. A method according to Claim 18 comprising: identifying a selected number of piglets in each litter that is less than the entire litter; dosing the selected piglets with the competitive exclusion product; thereafter removing the identified selected piglets from the litter; and feeding the milk replacer to the identified selected piglets.

26. A method according to Claim 25 comprising removing the identified selected piglets from the litter after a predetermined period of nursing at their sow.