MOF mania
Clare Schlegel's Modified Open Front barns use Mother Nature's ventilation for hydro-free hog raisingBY ROBERT IRWIN
It would be hard to find a more dedicated believer in Modified Open Front (MOF) barns than Ontario Pork director Clare Schlegel, Tavistock. His farm has been a mecca for potential converts to MOF.Sometimes referred to as Nebraska MOF, the structures are distinguished by a southward facing high wall. Instead of a conventional truss that creates an A-shaped roof, the MOF barn has a "monoslope." Although MOF has been mainly used for growing pigs, American agricultural engineers have used the concept for a solar-heated nursery. MOF barns are normally naturally ventilated with the primary air supply entering through the south wall; a few producers use fans for pit ventilation, however.
Why has Schlegel, also Ontario Pork vice-chairman, built three new MOF barns over the past decade, a time when most of the Ontario industry was moving to standardized conventional truss, fan-ventilated structures? "I know how to work it, it's simple, [there's] lots of fresh air and the ceilings aren't as high," explains Schlegel. "I wanted a barn where I could sleep at night without worrying about the hydro going off."
Schlegel, a finishing operator and chicken producer, is no zealot. With two neighbours, John Lichti and Richard Yantzi, he founded the AYS loop, which has conventional barns. "They work fine, too," he observes. To achieve proper ventilation patterns MOF barns are normally restricted to a maximum 36 feet in width, which means many producers faced with narrow farms or restrictive Minimum Distance Setback regulations can't consider MOF.
"If you're in a situation where you've got a lot of pigs in a small area then you've got to go to a wider area. That wasn't the case in my situation," Schlegel relates.
He says the extra length of a MOF barn means anyone using liquid or any kind of automatic feeding faces higher costs. "If you go to a big fan-ventilated barn with a centre aisleway and you've got rooms off each side, you're a lot more compact."
Pig performance is one advantage frequently cited by MOF barn proponents.
"I don't think you get a slowdown in the summertime in growth rates like you do in a fan-ventilated barn," Schlegel points out. His barns lack the sprinklers used for pig cooling in many barns.
"I don't think we need them," Schlegel asserts.
He concludes his MOF costs, $250 to $275 per pig space, are similar to conventional structures, though some believe MOF buildings are cheaper.
Fans, expensive chimneys and truss ceilings found in conventional naturally ventilated barns are eliminated. Schlegel eliminated expensive insulated concrete sandwich walls, using instead regular poured concrete with earth pushed against it to reduce frost penetration.
"It's a cold side anyway - Why would you put a sandwich wall there?" he asks. Schlegel uses an uninsulated ventilation curtain along the south wall. On cold days a layer of ice builds up on the lower part of the curtain and "makes perfect insulation," he relates. On sunny winter days the curtain opens wide and on most winter days it is normally open "a crack."
Like many conventional barns, Schlegel's building is insulated with sprayed urethane. There is four feet of manure storage below the totally slatted concrete floor. Ontario Ministry of Agriculture, Food and Rural Affairs engineer Franklin Kains, who has watched the evolution of MOF barns in Ontario since the late 1970s, concludes, "I never saw where there was a fundamental savings in cost."
German cows replace sows
German weaner producer raises top feeder pigs on dairy calf starter Elmar Ochmann has developed a simple and cheap feed supplementation for his weaners that has given him some of the best-performing feeding pigs in his region of Schleswig-Holstein, in Germany's northern tip near Denmark.Ochmann, who runs a 380-sow unit with PIC hybrid breeding stock producing 25 kg piglets for sale to feeders, weans at 21 days. But his young pigs remain on at least a part-liquid diet after weaning: He feeds them calf milk replacer.
"This is ordinary calf replacer that I mix with warm water - pails of water are left standing in the grower house to bring them to room temperature there," he explains. "I feed about 20 litres of the mix per 150 piglets twice a day for the first week, and this really seems to give them a good start."
The farmer says the idea to give liquid feed to the piglets came after he'd learned about Danish liquid feeding programs for weaners.
The pre-mix for the liquid feed was specially produced for young pigs. Ochmann says he decided to try the idea, "but with simpler - and much cheaper - calf milk replacer." Normal price for calf milk replacer in Germany is between C$60 and C$75 per 100 pounds, and some piglet milk replacers are selling for double that price.
Along with their liquid diet, the piglets get a special pre-starter feed from the English SCA company including 27.5-per cent skimmed milk and whey powder, 24-per cent crude protein and an energy value of 16 megajoules. Piglets reach between eight and nine kg liveweight in their first seven days away from mother.
Annual production from the Ochmann herd is between 23 and 24 weaners sold per sow. Piglets leave the farm with an average liveweight of 24 kg at 62 to 63 days. The Ochmann sows average 2.42 litters in the year with returns to service from 10 to 12 per cent.
Recent recordings of piglet performance during the first 12 days after weaning covered trials with two pens of 10 pigs - one pen with males, the other females. Results showed liveweight rose from an average 7.32 kg to 9.89 kg, giving an average daily weight gain for the male pen of 202 g and for the females of 225 g. Feed conversion ratio for all 20 pigs worked out at 1:0.96; the cost per kg weight gain was 96 cents.
"These sort of results are encouraging - but ultimately my business depends on how my pigs perform in the feeding unit," explains Ochmann . "Here there are no complaints either, with latest figures showing daily liveweight gain averaging 830 g and feed conversion at 1: 2.6."
Ruminations for the tractor cab
Here's a summary of recently reported and published swine research, gleaned from the Midwest Meetings of American Society of Animal Sciences, 1998.Valine 'n beans
The NRC-42 committee on swine nutrition investigated the effects of elevated dietary valine (a white, crystalline amino acid) concentrations on lactational performance of sows nursing large litters.Sows from six experiment stations (231 sows total) were fed one of four diets during 25 days of lactation. Diets were corn and soybean meal-based with a 0.9-per cent total lysine. Crystalline L-valine was used to provide different valine treatment levels of 0.8, 0.95, 1.1 and 1.25 per cent. All litters were adjusted to have 10 or more pigs on sows. Average daily feed intake did not differ. Sows weaned more than 10 pigs, and valine level had no effect on litter weight weaned, pig gain, sow weight change and return-to-estrus interval.
Rumination: No benefit seen in elevated dietary valine in sows fed corn-soybean meal diets with 0.9-per cent lysine and 0.8-per cent valine with sows nursing 10 or more pigs.
Boar next door
How much and what kind of daily boar exposure stimulates puberty in gilts?Gilts at the University of Nebraska were assigned randomly within litter to either one or two times per day boar exposure, either via fenceline exposure or physical contact. Another treatment group had continuous fenceline exposure to boars. Boar exposure lasted 10 minutes per exposure. Treatments began when gilts reached 160 days of age. Gilts were penned in groups of eight. Physical exposure induced first estrus sooner (20 vs. 30 days) which was also more synchronous than fenceline exposure. Age of puberty occurred about nine days earlier with physical exposure. Interval to first estrus was shorter in gilts receiving twice daily versus once daily contact (about seven days' difference). Gilts given continuous boar fenceline contact did not respond differently from the once or twice daily brief fenceline contact. Continuous fenceline exposed gilts had longer interval to estrus and later age at puberty compared to brief physical exposure treatment. Increased frequency of boar exposure (twice versus once per day) tended to decrease pubertal age but this was more effective for the fenceline exposed gilts rather than when physical boar exposure was used.
Rumination: The importance of early boar exposure, and the potential advantage demonstrated from early physical contact in young gilts, is still often ignored, especially with gilt developer and isolation barns. This technique likely has even more impact when gilts will be bred sooner than ideal and with later maturing, lean genotypes.
Pick by placenta
Will breeders be able to select for litter size using the ratio of piglet weight-to-placental weight as a measure of placental efficiency? Some day, perhaps, according to Iowa State University researchers Wilson, Biesen and Ford.Meishan conceptuses have been determined to have smaller placenta during gestation than contemporary breeds, but with no difference in uterine size. It is believed that the smaller placenta allows more fetuses to occupy the same uterine space. Rather than an increase in the surface area of attachment in proportion to fetal weight throughout gestation, placenta of Meishan simply has increased blood vessel density. These researchers estimated the relative efficiency of placenta by calculating piglet weight: placenta weight ratio. From their preliminary data, selection for a greater piglet weight per placenta weight was associated with larger litter size.
Rumination: Placenta size may have value in selecting for larger litter size.
Speed cycle
Weaned sows were treated with PG600 (a gonadotropin product used to induce estrus in weaned sows) during winter at Michigan State University.A field study involving five commercial sow herds was conducted to evaluate responses to PG600. Within farm weekly weaning groups, sows were blocked both by parity and by lactation length (less than 16 days or longer than 15 days). Parity 2 sows weaned after 15 days of age and treated with PG600 were most likely to express estrus among groups. Farrowing rate of Parity 3-6 sows was highest when weaned later than 15 days and treated with PG600. Parity 1 sows treated with PG600 had lower subsequent litter birth weight than untreated. Parity 3-6 sows weaned before 16 days and treated with PG600 had more total pigs born at next farrowing than untreated (11.5 versus. 9.9). No difference was observed when sows were weaned after 15 days of age. Rumination: It appears that PG600 can have different responses depending on parity and lactation length. Also, whereas it could increase litter size born with short lactation in parity 3-6 sows, farrowing rate may be improved with PG600 even when lactation lasts 16 days or longer.
Barrow booster
University of Nebraska researchers compared responses of barrows fed either a corn-soybean meal diet or diets supplemented with crystalline amino acids either on an ideal protein basis or to the pattern similar in corn-soybean meal diets.Barrows of a high-lean gain potential and weighing 71 pounds were fed either a corn-soybean diet without crystalline amino acids (C); or a diet using crystalline lysine, threonine, tryptophan and methionine to achieve the "ideal" protein balance (Ideal); or a diet using the crystalline amino acids to achieve the same pattern in corn-soybean diets as in treatment 1 (CSAA). The crude protein level in crystalline amino acid treatments was four per cent lower than the control diet. Pigs were fed for a 27-day period. Pigs fed the control corn-soy diet had greater rate of gain and gain per feed than pigs fed either the Ideal or CSAA diets.
Rumination: Simply balancing with the commonly available crystalline amino acids did not result in performance levels achieved with higher crude protein diets from corn-soybean. The reduction in protein was apparently too large despite formulating to either "ideal" or an equivalent amino acid ratio (pattern) of threonine, tryptophan and methionine to lysine.
Litters, lactation
University of Minnesota researchers looked at the factors associated with low subsequent litter size on commercial swine farms with short lactation.Sixteen farms with an average lactation length between 14.9 and 18.9 days and a total of 9,162 litter records (PigChamp) were used to investigate influences on litter size. Subsequent litter size response to either lactation length of wean-to-conception interval was influenced by parity. Subsequent litter size was not increased in parity 1 and 2 sows as lactation length increased but was increased in parity 3-6 sows. In parity 1 sows, 0.5 fewer pigs were subsequently farrowed when the wean-to-conception interval was six to 12 days as compared to one to five days. No litter size response was evident in multiparous sows to wean-to-conception interval. Smaller subsequent litter size was associated more with sows consuming less than 9.2 pounds daily than with sows consuming more than 9.2 pounds of feed in lactation.
Rumination: Limited productivity of parity 1 sows does not result from shorter lactation. In parity 3 to 6 sows the importance of parity management and lactation length increases and should result in larger litter size.
Copper and growth
University of Kentucky researchers compared copper-methionine hydroxy analog versus copper sulfate as a growth promoter for weanling pigs.A five-week nursery experiment evaluated a copper-methionine hydroxy analog (CuMHA) product and copper sulfate (Cu SO4) in diets. Pigs were weaned at 21 days. Treatments were: 1) basal with 16 ppm Cu; 2) 100 ppm Cu from Cu MHA; 3) 200 ppm Cu from CuMHA; 4) 200 ppm Cu from Cu SO4. Methionine levels were equal in all treatment diets. Feed intake was increased with the high copper diets. By the end of five weeks, feed intake and gain were significantly improved only in pigs fed the high copper level form Cu SO4.
Rumination: Copper sulfate as a growth promoter is very cost-effective and other sources generally have not shown either better performance response or lowered cost.
Ken Palen is livestock specialist with Kenpal Farm Products
Odours away
Danish manure injector keeps the smelly liquid out of sight - and nose Like their compatriots over in Holland who have 15 million people and as many pigs, Dutch-descent producers John and Gerard Gielen of Crediton, Huron county, have been injecting liquid hog manure under the soil for years.For the past 15, the Gielens have been tinkering with different methods of slicing the nutrient-rich, but smelly, liquid beneath the soil to keep it out of mind and nose. They currently inject 100 acres of fall wheat stubble with slurry from a couple of hundred sows, via a toolbar behind a Nuhn tanker with tines spaced at two feet.
The Gielens, who have modified much of their machinery, liked what they saw at the North American introduction of the Kongskilde Vibro Flex 4300 injector in Exeter last month. Liquid manure passed from the Nuhn 4,000-gallon tanker through a tube to a distributor mounted on top of the injector, hitched to the tanker with a three-point linkage. From there, manure was chopped by two knives inside the distributor, and sent via smaller tubes to the 14-foot cultivator's four rows of high-clearance tines spaced every 8.8 inches.
Kongskilde Ltd. president and general manager George Poole said the key to the unit is the vibrating action of the S tines. Working as deep as seven to eight inches, each tine "builds up torque, and provides for vibrations down by the share...taking out air pockets, where gas can escape," he says.
The granulated soil in the seedbed creates an absorbent layer that "acts as a blotter," wicking down liquid manure. Meanwhile, the surface area is coarser for higher residue farming, Poole said.
He added the unit would most likely fit as an autumn tillage tool like chisel plowing.
Once the demonstration unit had passed through the dryish clay soil east of Exeter, there was nary a whiff of the dark liquid seen coursing through the translucent pipes. In fact, said Roeland Luijck, group product manager for soil based at Kongskilde's headquarters in Soro, Denmark, ammonium losses to the air are as low as one per cent depending on soil type.
While the average spreading rate in Ontario is 3,000 to 5,000 gallons per acre, the Kongskilde injector could apply 150 cubic metres per hectare, about 13,000 gallons per acre. While he didn't advise it, "it's absolutely no problem to get rid of double with this machine and also to seal it off," Luijck said.
He added that the manure must be clean of slugs such as stones, wood, or baler twine, which can't be chopped at the injector because of the action of the two knives.
John Gielen says he is impressed with the "smooth and level job" done by the cultivator, versus his setup at two-foot spacing: "It's enough cultivation to bring you through the winter, and then work it up in the spring."
If he has any criticism, Gielen says the system, pulled by a 225-hp Deere 8400, was a bit power hungry: He pulls a 5,000-gallon tank and injector with a 200-hp 8300.
As for the power needs, Dennis Nuhn, president of Sebringville-based Nuhn Industries, says it's required for the amount of tillage with four rows of tines: "If you want tillage, you have to have power." Nuhn says he likes the tillage action of Kongs-kilde's Vibro Flex system and is working on a two-bar tool.
Nuhn also plans to rework the three-point hitch linkage between the tank and implement - not an easy task, he says, with the "weight and balance problems" of pulling a heavy tool behind a tanker. The front of the tank keeps wanting to ride up.
While injection slows the Gielens down a bit compared to straight spreading, and wet falls sometimes make injection impossible, injection is "the way to go," says John. "It eliminates the problem of surface runoff going into the low hollows and getting into the tiles. [Injection] puts it where it is and it stays there."
The Vibro Flex 4300 injector including stubble cultivator, levelling attachments and slurry injection equipment will likely retail at around $25,000, said Poole.