bluuebunny/crossref_metadata_2025 huggingface dataset:
DEVELOPMENT OF A NEW BREED OF PIGS: THE LACOMBE: III. PUBLIC DISTRIBUTION AND PROPAGATION
Authors: Fredeen H. T. , Stothart J. G.
Published: March 2010

The Lacombe, accepted for registration, as a new breed of pigs in 1957, was released to the public in 1958. In 1968, Lacombes comprised 11.9% of all swine pedigrees issued in Canada. This number was contributed by 72 breeders. Lacombes tested under the national Record of Performance swine testing program have averaged approximately 10% faster in growth rate than Yorkshires, and produce carcasses of equivalent merit.Selective registration based on Record of Performance tests of parents or sibs has been an integral part of the Lacombe Breed Association by-laws since the Association was formed in 1959. This registration procedure has imposed greater inputs and costs relative to both the R.O.P. test and the mandatory culling levels than are required for other breeds. Although these appear to have adversely affected rate of propagation, they have exerted a beneficial influence on herd size.Selective registration has not resulted in any apparent positive genetic trends for Lacombe performance. Factors contributing to this situation include the retrospective nature of the test proofs required for registration, a long generation interval, and the fact that nongenetic differences between herds have been inadequately discounted in choosing replacement sires.
SEPARATION AND GENE FREQUENCIES OF BLOOD SERUM TRANSFERRIN, CASEIN AND BETA-LACTOGLOBULIN LOCI OF DAIRY CATTLE AND THEIR EFFECTS ON CERTAIN PRODUCTION TRAITS
Authors: Hoogendoorn M. P. , Moxley J. E. , Hawes R. O. , MacRae H. F.
Published: March 2010

A procedure was developed for the simultaneous phenotyping of β-casein and β-lactoglobulin at acid pH. The population structure of the transferrin, αs1-casein, β-casein, κ-casein and β-lactoglobulin loci as well as their relationship with different production traits was studied for some herds of Ayrshire, Canadian, Holstein-Friesian, Jersey and Milking Shorthorn breeds representing approximately 1300 animals. The transferrin alleles, Tf A, D1, D2 and E were found in the Ayrshire and Holstein-Friesian breeds. The αs1-casein alleles A, B and C were observed; the A allele was present in the Holstein-Friesian cattle only. The A1 and A2 alleles of β-casein were found in all the breeds, while the C allele was present in the Milking Shorthorn and the A3 allele in the Holstein-Friesian breed. The B allele was absent only from the Milking Shorthorn breed. Both A and B alleles were present at the κ-casein locus in all breeds. Both β-lactoglobulin alleles A and B were observed in all breeds. Some relationships were found between the different loci (alone and in combination) and the percentage butterfat, percentage protein and percentage lactose. Differences between breeds with regard to superior genotypes were observed.
GROWTH AND DIGESTIBILITY STUDIES TO EVALUATE RAPESEED MEAL AS A PROTEIN SUPPLEMENT FOR SWINE
Authors: Bayley H. S. , Cho C. Y. , Summers J. D.
Published: March 2010

A 15% protein corn-soy finisher diet was compared with an isonitrogenous corn-soy-rapeseed meal diet. The two diets were fed either as meal or as pellets. Twenty female pigs received each of the four experimental treatments from 45 to 90 kg liveweight. The treatments did not affect feed consumption and the substitution of 11% rapeseed meal in the diet fed as meal did not affect growth rate. Pelleting increased the growth rate of pigs on the corn-soy diet, but had no effect on the growth rate of the pigs receiving the corn-soy-rapeseed diet.The digestible energy value of the rapeseed meal and of the reground, pelleted rapeseed meal was determined using barrows of 50 kg liveweight. The digestible energy value of the rapeseed meal (2.74 kcal/g) was increased to 3.02 kcal/g by steam pelleting and regrinding.
CHROMIC OXIDE IN DIGESTIBILITY STUDIES WITH LACTATING DAIRY COWS
Authors: Hoogendoorn A. L. , Grieve C. M.
Published: March 2010

Chromic oxide (Cr2O3) in paper pellets was used as an indicator for digestibility studies with four Holstein-Friesian cows fed rations composed of different roughage to concentrate ratios. Cows A and B received one pellet, or 3.46 g of Cr2O3, whereas cows C and D received three pellets, or 10.38 g of Cr2O3, daily.Recovery of Cr2O3 in the feces varied from 84 to 103% for animals A and B and from 92 to 95% for animals C and D. The coefficients of apparent digestion of dry matter were lower (P < 0.01) when the Cr2O3 method was used instead of the conventional method. When samples were taken at 0500, 0900, 1300 and 1700 hours, the Cr2O3 method gave average estimates of digestibility for animal pairs A, B and C, D that were 94.2 and 97.5% of those obtained by the conventional method. Standard deviations for both the Cr2O3 and conventional methods were relatively high.Excretion patterns of Cr2O3 were not signicantly correlated with those of crude protein, phosphorus and calcium. The average concentrations of crude protein, phosphorus and calcium in compounded feces samples collected at 0500, 0900, 1300 and 1700 hours were 101.3, 100.6 and 96.7% of those in samples of the total excretions.The daily administration of 10.38 g of Cr2O3 at 0900 hours for eight days, and the collection of fecal grab samples at 0500, 0900, 1300 and 1700 hours daily during the last five days seemed satisfactory for estimating apparent digestibility of dry matter.
EFFECT OF CONTINUOUS FEEDING ON THE COMPOSITION OF RUMEN DIGESTA
Authors: Ibrahim E. A. , Ingalls J. R. , Phillips G. D.
Published: March 2010

not available
NUTRITIVE VALUE OF SOME GHANAIAN FEEDSTUFFS
Authors: OWUSU-DOMFEH K. , CHRISTENSEN D. A. , OWEN B. D.
Published: March 2010

The nutrient composition of 12 Ghanaian feedstuffs was studied by chemical or microbiological analysis for amino acids, B-vitamins, calcium, phosphorus, gross energy and the proximate principles. Digestibility coefficients for dry matter, energy, and protein were determined with adult male mice. The amino acid contents of the feedstuffs were compared with that of whole egg, according to chemical score and essential amino acid index methods. The nutritive values of five high protein Ghanaian feedstuffs were determined, with weanling male mice, by the nitrogen balance and protein efficiency ratio methods in diets containing 8, 11, 14, and 17% protein. Heating cowpeas and bambarra beans was found to increase the digestibility and protein utilization of the legumes. The composition of the feedstuffs was, with a few exceptions, similar to that reported elsewhere. Notable differences included the generally low calcium content of the Ghanaian feedstuffs, the high cellulose content of palm kernel cake and the low methionine and cystine content of the feedstuffs.
CONTROL OF ESTRUS AND LITTER SIZE IN GILTS WITH AIMAX (ICI 33,828) AND PREGNANT MARE’S SERUM
Authors: BAKER R. D. , SHAW G. A. , DODDS J. S.
Published: March 2010

A field trial was conducted to investigate effects of pregnant mare’s serum gonadotrophin (PMS) on estrus, farrowing rate and litter size in AIMAX-treated gilts. A total of 177 Yorkshire × Landrace gilts from 7 to 9 months of age and weighing 95 to 115 kg were group fed an average of 1.8 kg of a 14% sow ration containing 100 mg of AIMAX per female per day for 20 days. Twenty-four hours after the last feeding of AIMAX, 59 gilts were injected with 1000 I.U. PMS, 59 were injected with 1500 I.U. PMS and the remaining 59 served as noninjected controls. Gilts showing estrus were mated naturally or artificially inseminated with 100 ml of semen. None of the gilts showed estrus during AIMAX treatment. Injecting PMS increased (P < 0.05) the number of gilts bred between the 5th and 7th days after AIMAX withdrawal and reduced (P < 0.05) the interval between AIMAX withdrawal and breeding by 2.0 days. Injecting 1000 LU. PMS increased (P < 0.05) the total number of pigs born per litter by 2.0 pigs and increased (P < 0.05) the number of live pigs per litter 12 to 24 hours after farrowing by 1.5 pigs. In contrast, injecting 1500 I.U. PMS had no significant effect on litter size. These results demonstrate that 1000 I.U. PMS injected 24 hours after AIMAX withdrawal was effective in increasing the degree of synchronization and litter size of gilts under farm conditions.
BLOAT INVESTIGATIONS. THE THRESHOLD FRACTION 1 (18S) PROTEIN CONCENTRATION FOR BLOAT AND RELATIONSHIPS BETWEEN BLOAT AND LIPID, TANNIN, Ca, Mg, Ni AND Zn CONCENTRATIONS IN ALFALFA
Authors: MILTIMORE J. E. , McARTHUR J. M. , MASON J. L. , ASHBY D. L.
Published: March 2010

Incidence of lethal legume bloat in cattle was related to Fraction 1 (18S) protein concentration in mechanically grazed alfalfa over two grazing seasons. In the second year, lipid, tannin, Ca, Mg, Ni and Zn concentrations in the alfalfa were related to bloat incidence and to Fraction 1 protein concentration.Fraction 1 protein was most closely associated with bloat as the average bloat incidence increased from 2 to 35% over the bloating range of Fraction 1 protein. Comparable increases of bloat for Ca, Ni and Zn were 10.0, 10.0 and 8.5%, respectively. Bloat had a threshold level of 1.8% Fraction 1 protein, below which bloat did not occur and it was the only variable with a threshold level. This level of 1.8% can be used by the plant breeder or agronomist as a goal in producing a nonbloating alfalfa by selection or by management.Calcium, Ni and Zn were significantly associated with bloat and Ca was also associated with Fraction 1 protein. Nickel and Zn were associated with twice as much bloat as Ca when the effect of Fraction 1 protein was removed. However, there is no explanation for the relationship between Ni and Zn concentrations and bloat. Lipids and tannins were positively associated with Fraction 1 protein but they were not significantly associated with bloat (P < 0.05). Magnesium was not related to either bloat or Fraction 1 protein.This is the first report showing the threshold Fraction 1 protein content below which bloat did not occur. We have shown previously that rumen pH is also a trigger mechanism. In addition, Ca, Ni and Zn also have been found to have an important relationship to the amount of bloat that occurred. These interacting factors can explain much of the sporadic incidence of bloat and variable severity within and between both cattle and ranches.
EFFECTS OF COLD ENVIRONMENTS ON THE ENERGY EXCHANGES OF YOUNG BEEF CATTLE
Authors: WEBSTER A. J. F. , CHLUMECKY J. , YOUNG B. A.
Published: March 2010

Groups of four heifers were kept over winter at 20 C (controls) or outdoors with (sheltered) or without (exposed) shelter. Weather conditions were severe. Mean January temperature was −28 C. All animals received the same amount of grain. Calves in the control, sheltered and exposed groups ate on average 9.0, 11.3 and 10.9 g hay/kg body weight per day and gained, over winter, 156, 158 and 140 kg, respectively. Growth of new hair was similar in all groups. However, total hair cover in the cattle kept outside was, in February, twice that of the controls. This increase was attributed to reduced hair shedding. Tissue insulation increased throughout in all groups. External insulation was markedly reduced by exposure of the animals to wind. The influence of coat depth on external insulation was small. Still air critical temperature for the controls fell from 7 to −2 C during the experiment. The effect of acclimatization was to reduce critical temperature to −18 C in the sheltered group during February.The results are discussed with respect to the nature and extent of environmental control required for beef production in cold climates.
INFLUENCE OF SELENIUM AND LINOLEIC ACID ON THE DEVELOPMENT OF NUTRITIONAL MUSCULAR DYSTROPHY IN BEEF CALVES, LAMBS AND RABBITS
Authors: JENKINS K. J. , HIDIROGLOU M. , MACKAY R. R. , PROULX J. G.
Published: March 2010

A study was conducted to assess the effects of dietary linoleic acid and selenium on the development of myopathy in beef calves, lambs and rabbits fed a low-selenium hay. Oral administration of selenium to either ewes (14 mg/week) or their nursing lambs (7 mg/week) resulted in a marked reduction in the incidence of dystrophy in the lambs. Linoleic acid had no inhibitory effect on selenium protectivity, whether given to the lambs or the ewes. Suckling calves of dams fed the dystrophogenic hay developed myopathy similar to that observed in lambs. Eight of the 11 affected calves recovered spontaneously from the disorder without treatment. Oral administration of linoleic acid to calves did not promote a higher incidence of dystrophy or inhibit the protectivity of selenium. In addition, the fatty acid did not appear to affect the recovery process. No muscle degeneration was observed in any of the calves given selenium (5.4 mg/week). No dystrophy occurred in rabbits consuming the low-selenium hay. When 1% linoleic acid was incorporated into the rabbits’ diet, severe muscle degeneration developed within 4–6 weeks and selenium was completely ineffective in preventing the disorder.
CALCIUM, PHOSPHORUS AND VITAMIN D REQUIREMENTS OF CHICKENS
Authors: SUMMERS J. D. , PEPPER W. F. , SLINGER S. J.
Published: March 2010

Two experiments were conducted to investigate the interrelationships of calcium, phosphorus and vitamin D3 on weight gain, feed efficiency and percent bone ash. With White Leghorn cockerel chicks, carried to 4 weeks of age, a significant improvement in feed efficiency was observed with increasing levels of vitamin D3. With a faster growing strain of broiler type chicks, a significant interaction between calcium and vitamin D3 and calcium and phosphorus was observed with the 58-day weight. Interactions were also observed between calcium and vitamin D3 and vitamin D3 and phosphorus as measured by percent bone ash. The results would suggest that it is not possible to state specific requirements for calcium, phosphorus or vitamin D3 without considering the levels of these three nutrients and also the level of phytin phosphorus in a diet.
INFLUENCE OF SUBSTITUTING HIGHER FIBER INGREDIENTS FOR CORN ON THE DIGESTIBILITY OF DIETS AND PERFORMANCE OF SOWS AND LITTERS
Authors: ZIVKOVIĆ S. , BOWLAND J. P.
Published: March 2010

Twenty-four Swedish Landrace × Large White sows were individually fed one of four diets throughout gestation and lactation under confinement conditions at the Sombor Kombinat, Yugoslavia. The 80% yellow corn in the control diet was replaced by 80% corn and cob meal, 50% corn and cob meal and 30% dried beet pulp, or 50% corn and cob meal and 30% wheat middlings in the other higher fiber diets. A standard protein supplement of 10% soybean meal, 4% sunflower meal and 3.5% fishmeal was included in the diets.Observed total digestible nutrients (TDN) and digestible energy (DE) were higher than calculated for the diets containing the higher fiber ingredients, suggesting that mature sows can digest some of these ingredients to a greater extent than can younger pigs on which analysis tables are based. The calculated DE in kcal/kg of corn and cob meal was 3428, dried beet pulp 3520, and wheat middlings 3155, assuming corn to be 3610 kcal/kg. The values used in formulation were 3080, 2860 and 3210 kcal/kg for the first three ingredients. Sows were most efficient in digesting organic nutrients on the 90th day of gestation, poorest on the 10th day of lactation and intermediate on the 30th day of gestation.Average number of pigs born alive was 9.9 and weaned was 8.8, with average pig weights at birth averaging 1.44 kg and at 5-week weaning, 14.1 kg. There were no significant differences between lots in litter performance, except that TDN required per kg gain adjusted for sow weight loss during lactation was greater for sows receiving 30% dried beet pulp. Sow gain during gestation was lower for this lot. Despite an overall DE intake for the complete reproductive cycle that was 23% in excess of present U.S. NRC nutrient requirements, the mature sows averaged only 3.6 kg heavier when they weaned their litters than when they were bred.
INFLUENCE OF PHOTOPERIOD AND METHOD OF DECREASING PHOTOPERIOD ON MORTALITY ATTRIBUTED TO MAREK’S DISEASE AMONG MEAT PARENT FEMALE CHICKENS
Authors: Proudfoot F. G.
Published: March 2010

not available
A REFRIGERATED MILK FEEDER FOR LAMBS WEANED AT THREE DAYS OF AGE
Authors: Bouchard Réjean , Bernard Camille , Brisson G. J.
Published: March 2010

not available
AERIAL TRANSPORT OF FERTILIZED PIG OVA
Authors: Baker Robert D. , Dziuk Philip J.
Published: March 2010

not available
EFFECTS OF SAMPLING LOCATION AND CARCASS FATNESS ON TENDERNESS OF STEAKS FROM THE LONGISSIMUS DORSI OF YEARLING SHORTHORN BULLS
Authors: MARTIN A. H. , FREDEEN H. T. , WEISS G. M.
Published: March 2010

Tenderness variations within and between steaks, sides and carcass were examined from the shortloins of three commercial carcasses of unknown history. In a second experiment the influence of carcass and beef fatness on tenderness of rib steaks of 69 Shorthorn bulls was also investigated. For both experiments tenderness was evaluated subjectively by means of a six-member taste panel and objectively with a Warner-Bratzler shearing device. Correlations between the two tenderness evaluation methods ranged from 0.55 to 0.83. For both types of evaluation, steaks in the 11th–12th rib were significantly more tender than steaks further back along the loin. There was considerable within-steak variation which was of a systematic nature, cores from the region of the backbone being significantly more tender than cores located toward the lateral edge of the rib-eye. Between-carcass variation was large relative to that within carcasses, and important differences in tenderness between steaks from bulls of very similar background were established. All measures of fatness, intra- and inter-muscular and subcutaneous, were positively correlated. Correlations with tenderness evaluations were significant for percent intramuscular fat only. These were not large, however, (100 r2 = 9%) for either method of tenderness evaluation.
EFFECT OF DIETARY TRITICALE ERGOT ON THE PERFORMANCE AND SURVIVAL OF BROILER CHICKS
Authors: BRAGG D. B. , SALEM H. A. , DEVLIN T. J.
Published: March 2010

Two chick feeding trials were conducted to test the effect of dietary Triticale ergot and physical form of the diet on growth, feed per gain (F/G) ratio and mortality of broilers. Results indicated that chicks can tolerate 0.8% dietary ergot without adverse effect. Dietary ergot (1.6%) significantly depressed growth and increased the F/G ratio, which was not significantly different from control diets. Ergot levels of 3.2, 6.4 or 12.8% in wheat rations resulted in poor growth, inferior F/G ratio, toxicity signs (e.g. the toe nails, toes and beak turned black), and finally high mortality. The presence of Triticale (trial 2) in the mash diet appeared to alleviate part of the growth depression and improved the F/G ratio of chicks fed 1.6% ergot compared with those fed wheat and Triticale control rations. The Triticale diet in pellet form decreased growth significantly from that of chicks fed wheat, Triticale, or 1.6% ergot and Triticale diets in mash form.
ENERGY UTILIZATION IN THE CHICK IN RELATION TO CERTAIN ENVIRONMENTAL STRESSES
Authors: LEI K. Y. , SLINGER S. J.
Published: March 2010

Reductions in weight gain, feed consumption and feed efficiency resulted under the stress of water restriction or high population density. The metabolizable energy (ME) content of the feed was unaffected by the severity of the stresses. Elevated and depressed environmental temperatures resulted in reductions in weight gain and feed efficiency, but there were no alterations in the ME content of the feeds. Water restriction decreased the sucrase activity, but not the maltase activity in the intestinal mucosa. Overcrowding had no effect on the level of these mucosal enzymes. At adverse temperatures mucosal sucrase and maltase activities were significantly higher for birds on a low energy than for those on a high energy diet. On the low energy, but not the high energy regime, the sucrase and maltase activities were increased at the elevated and depressed environmental temperatures.
EFFECT OF METHIONINE SUPPLEMENTATION POSTERIOR TO THE RUMEN ON NITROGEN UTILIZATION AND SULFUR BALANCE OF STEERS ON A HIGH ROUGHAGE RATION
Authors: STEINACKER G. , DEVLIN T. J. , INGALLS J. R.
Published: March 2010

The effect of post ruminal methionine, dietary methionine or dietary sulfur (S) supplementation on nitrogen retention and S excretion was determined by using three Holstein steers fitted with abomasal cannula in a 3 × 3 Latin square design. The basal diet was fed ad libitum and consisted of ground timothy hay and concentrate in a 5:1 ratio. The diet contained 12% crude protein with urea contributing about 40% of the total nitrogen. Elemental S (0.05%) or methionine (0.22%) was added to the diet while a similar quantity of methionine was infused into the abomasum. Abomasal infused methionine compared with supplemental dietary S or methionine resulted in a 16.6 and 23.9% increase in percent of absorbed nitrogen retained, which was not statistically significant (probability approximately 0.25). Sulfur intake and apparent S digestibility was similar for all treatments; however, urinary S concentration tended to be lower for the elemental S treatment (probability approximately 0.10). Sulfur retention was higher (P < 0.05) with supplementary elemental S than when a similar amount of S was consumed or infused in the form of methionine.
TRYPTOPHAN ABSORPTION AND METABOLISM IN SHEEP
Authors: CANDLISH ELIZABETH , STANGER N. E. , DEVLIN T. J. , LaCROIX L. J.
Published: March 2010

DL-tryptophan–14C(U)–benzene ring labelled material was injected into the rumen of two sheep. Label appeared in portal blood prior to its appearance in jugular blood. Most of the label in the blood samples occurred in tryptophan. Label appeared in the urine within 10 min of introducing the labelled tryptophan into the rumen. Urine samples were examined for label appearing in tryptamine, indoleacetic acid and tryptophan. Less than 20% of the label in the urine was in the analyzed compounds with tryptamine showing negligible activity. Rapid absorption of tryptophan from the rumen and reticulum of two other sheep was shown. Absorption of 26.7% of the total labelled tryptophan injected occurred with the washed rumen technique, and 68.8% was absorbed when the whole rumen technique was employed.
COMPARISON OF SOME MILLING PRODUCTS OF BARLEY AND RYE WHEN FED IN DIETS TO RATS
Authors: FRIEND D. W.
Published: March 2010

Groups of rats averaging 167 g initial body weight were fed ad libitum a basal diet to which was added either ground barley, ground rye, barley flour + rye bran or rye flour + barley bran as 42% of the total diet. The 28-day experiment included a 7-day N-balance trial. Rats given the diet containing barley flour + rye bran had the highest feed intake (698 g), gained the most weight (160 g) and retained more N (2.12 g) than did rats fed any of the other diets. Weight gains with the rye flour + barley bran diet, although better than with the ground rye diet, were less than with the other two diets. Rye flour, rather than rye bran, appeared to elicit the lower feed consumption associated with diets containing rye grain.
PERFORMANCE AND PROTEOLYTIC ENZYME ACTIVITY OF THE SUCKLING PIGLET CREEP-FED AT ONE OR THREE WEEKS OF AGE
Authors: FRIEND D. W. , GORRILL A. D. L. , MacINTYRE T. M.
Published: March 2010

A "split-litter" technique was used with 19 litters of suckling piglets from birth to 5 weeks of age to determine the effects of providing creep-feed from 1 or 3 weeks compared with controls given no creep-feed. Measurements included growth, feed and water intake, hematocrit, carcass composition and trypsin and chymotrypsin activity of the pancreas and intestinal digesta from 3- and 5-week old piglets. Daily gain by piglets creep-fed at 1 week appeared to be greater than that by piglets creep-fed at 3 weeks. At 5 weeks, the hematocrit of control piglets was below that of those creep-fed from 1 week (P < 0.05) and 3 weeks of age, but the levels of all piglets were below the 1-week values. Early, compared with no creep-feeding increased by 12 and 3% the trypsin and decreased by 7 and 5% the chymotrypsin activities of the pancreas at 3 and 5 weeks of age, respectively. Creep-feeding increased the trypsin and chymotrypsin (P < 0.05) activity of the digesta from 5-week old piglets.
GENE SEGREGATION AT THEF-VANDTf-LOCI IN SOME CATTLE BREEDS
Authors: KRAAY G. J.
Published: March 2010

A study was made of the Mendelian segregation of genes controlling the F-V bloodgroup system and the Tf serum protein system in four cattle breeds. From the parentage verification cases in which both parents and their offspring had been blood typed, cases were selected in which one or both of the parents were heterozygous for one or both systems. In the F-V system a deviation was found from the expected ratios resulting in an increase of the frequency of the gene for the blood-group F in the offspring, in three of the four breeds studied. The explanation that this is caused by a mother-fetus incompatibility was not confirmed by the data obtained on the fourth breed. In the Tf-system, an excess of heterozygous offspring of type AD from AD-type dams and a shortage of homozygous offspring from those dams, compared with the expected numbers, was observed. No explanation for this phenomenon is given, since this material does not permit a detailed study of possible causes. There was no indication of a mother-fetus incompatibility with respect to the Tf types in this material.
HOMOGAMETIC HETEROSIS IN CROSSBREEDING EXPERIMENTS WITH SHEEP
Authors: FAHMY M. H.
Published: March 2010

Data from two crossbreeding experiments with sheep were analyzed to test the difference in heterosis between males and females in the F1, backcross, and three-breed crosses. The characters studied were birth and weaning weights and preweaning daily gain. In the F1 no marked differences in heterosis in weaning weight and preweaning gain were observed between sexes while in birth weight the two experiments gave conflicting results. In backcrosses and the three-breed crosses, females showed higher heterosis than males in the three characters studied. The ratios of heterosis in males to that in females did not support the hypothesis that differences between sexes in heterosis are due to the action of the sex chromosomes. The results of the two experiments suggested a possible interaction between the X and Y chromosomes of different breeds. The results in general did not give good evidence of homogametic heterosis in crossbreeding experiments with sheep.
ADDITION OF SAWDUST OR SHAVINGS TO MILK REPLACER FOR CALVES
Authors: Gorrill A. D. L.
Published: March 2010

not available
EFFECTS OF METHYL MERCURY TREATED FEED ON THE MORTALITY AND GROWTH OF LEGHORN COCKERELS
Authors: Fimreite Norvald
Published: March 2010

not available
A NON-DESTRUCTIVE EGGSHELL STRENGTH TESTER
Authors: Voisey Peter W. , Foster W. F.
Published: March 2010

not available
SEPARATION AND IDENTIFICATION OF AMINO ACIDS PRESENT IN RUMEN MICROORGANISMS
Authors: Ibrahim E. A. , Ingalls J. R. , Bragg D. B.
Published: March 2010

not available
DESIGN OF A LOW-COST ARTIFICIAL RUMEN FERMENTOR
Authors: Burgess P. L. , Wood F. A.
Published: March 2010

not available
LIVE PERFORMANCE AND CARCASS CHARACTERISTICS OF BEEF BULLS IN RELATION TO SELECTION FOR YEARLING WEIGHT
Authors: MARTIN A. H. , FREDEEN H. T. , NEWMAN J. A.
Published: March 2010

Data over two years on a total of 149 Shorthorn bulls from a closed herd under direct selection for yearling weight were used to examine line differences in carcass yield and quality and to evaluate relationships between live performance and carcass yield and quality. No significant differences [Formula: see text] in performance or carcass data between control and selected lines were apparent in 1967. However, in 1968 bulls from the selected line were heavier at slaughter (470.5 kg vs. 441.8 kg), their carcasses contained more kidney fat (9.14 kg vs. 8.46 kg), and they had larger loin eye area but smaller weight-adjusted loin eye area. Rate of gain was superior for the selected line whether examined as live-weight, carcass weight, trimmed primal cut weight or lean weight per day of age. There were no significant differences between lines for percent fat, lean or bone in primal cuts, or for rib fat thickness, percent trimmed prime cuts, percent seam fat, muscle/bone and hind/front ratios, or for chemical composition or tenderness evaluations of the longissimus dorsi. Averaged over the two years and at the same averaged slaughter weights (418 days), selected-line bulls produced a significantly greater quantity of total carcass, of trimmed primal cuts and of total lean than did the control-line bulls; selection for yearling weight appeared to have been effective in increasing rate of lean growth. Phenotypic correlations indicated that liveweight/day of age was more highly related to variation in lean growth rate than growth rate of fat. From 20 to 60% of the variation in wholesale cut weights was associated with differences in rate of gain. Distribution of the gains was little influenced by rate of gain. Tenderness evaluations were not related to live performance.
EFFECTS OF GENOTYPE, AGE AND ENVIRONMENT ON THE INCIDENCE OF MORTALITY DUE TO MAREK’S DISEASE
Authors: PROUDFOOT F. G.
Published: March 2010

The effect on the incidence of mortality due to Marek’s disease resulting from rearing Leghorn strains of chickens on new versus old litter, and exchanging at different ages between these two environments, were evaluated. The effect of temporarily moving birds from these low to high exposure regimes for a two-week period were also investigated. A significant difference among genotypes for mortality due to Marek’s disease was demonstrated. Results of these experiments also revealed no advantage in growing birds on old litter compared with new litter. When birds were transferred from environments of high to low exposure, mortality was higher than when birds were transferred in the opposite direction. This indicates that if birds are to be moved from rearing quarters to a clean, low exposure locale, it may be desirable to transfer some of the litter from the rearing quarters to the clean premises with the birds.
FEEDING VALUE OF FORAGE AS FED TO STEERS AND ESTIMATED BY IN VITRO DIGESTION
Authors: TROELSEN J. E. , BEACOM S. E.
Published: March 2010

The digestibility and intake of 23 hays and three silages were determined in two experiments with Hereford steers averaging 215 kg at the start of the test. Each forage was fed in a chopped (4 to 6 cm) form as the sole diet to two steers for 56 days. Voluntary intake and body weight gain during the fourth through the seventh week were used as measures of animal performance. Digestibility was determined by collecting all the feces during the eighth week, allowing for a three-day lag between intake and excretion. The forages included grass, legume and cereal hays, and cereal and legume cereal silages produced under a wide range of conditions. The concentration of in vitro digestible organic matter (DOM) in the forage was highly correlated with gain (r = 0.57 and 0.86) and intake of digestible energy (DE) (r = 0.62 and 0.89). The voluntary intake by the steers was comparable with that by sheep in earlier experiments at two other locations, when the intake was based on metabolic body size, and on similar in vitro DOM or in vivo DE concentrations in the forage. Differences in intake between experiments followed the same pattern as feed allowance in excess of intake, but the effect of in vitro DOM or in vivo DE content on intake was apparently the same in each experiment. This supported the theory that regressions of DE intake by sheep on in vitro DOM content of forage will serve as a measure of the feeding value, providing that appropriate experimental conditions are maintained.
DIRECT EFFECTS OF COLD WEATHER ON THE ENERGETIC EFFICIENCY OF BEEF PRODUCTION IN DIFFERENT REGIONS OF CANADA
Authors: WEBSTER A. J. F.
Published: March 2010

Direct measurements of the energy exchanges of cattle in cold and windy environments were used to derive partial regression equations predicting the effects of air temperature and body weight on tissue insulation, and wind speed and coat depth on external insulation. These measurements were combined with estimates of thermoneutral heat production to predict still air critical temperatures for feeder steers, pregnant cows and growing calves. These values ranged from −31 to −38, −11 to −23, and −16 to −21 C in the three groups, respectively. Meteorological records from different sites in Canada showed that cold has a negligible effect on the energetic efficiency of sheltered feeder cattle. The effects of cold on pregnant cows and growing calves are significant but not excessive. Examples are presented of the extent to which wind, sunshine and precipitation may influence critical temperature and the results are discussed in terms of regional disparities within Canada in the costs of keeping beef cattle, the economics of environmental control and the recommendations with respect to beef production of the Canadian Federal Task Force on Agriculture.
EFFECT OF FORMALIN-TREATED WHEAT IN THE DIET ON THE PERFORMANCE OF GROWING CHICKS
Authors: BRAGG D. B. , SHARMA H. R. , INGALLS J. R.
Published: March 2010

White Leghorn chicks were fed wheat that was stored under the influence of formalin, and wheat that was recently treated with formalin. Also, samples of each of the formalin-treated wheats were dried and fed to chicks during a four-week test period. Results showed that chicks fed the wheat which was stored under the influence of formalin had a similar rate of growth, feed intake and feed efficiency ratio as those fed the control diet. Dietary wheat recently treated with a high level of formalin resulted in a depression in growth and feed intake as well as poorer feed efficiency ratio. Drying either of the wheat samples after formalin treatment resulted in poor chick performance due to a decrease in feed intake.
EFFECT OF ALTERNATION BETWEEN HIGH AND LOW ENERGY DIETS ON THE PERFORMANCE OF GROWING SWINE
Authors: CHEEKE P. R. , KENNICK W. H.
Published: March 2010

The response of growing pigs receiving a low energy diet (LE ration) to periodic exposures to a high energy diet (HE ration) was studied. Forty-eight Berkshire × Yorkshire barrows of approximately 23 kg body weight were divided into six equal groups receiving one of the following treatments: HE control, LE control, and alternations between the LE and HE rations in cycles of 5 days LE: 1 day HE. 4 days LE: 1 day HE, 3 days LE: 1 day HE, and 2 days LE: 1 day HE. The average daily gain of the HE control was significantly greater (P < 0.01) than that of the LE control. The alternated groups did not grow significantly faster than the LE control; thus, compensatory growth responses did not occur. Feed intake of the LE control was higher than that of the HE control. The alternated groups reduced their intake of the LE ration relative to the LE control, and consumed significantly greater amounts (P < 0.001) of the HE diet than did the HE controls. The pigs may have learned to anticipate their period of exposure to the HE diet, since the consumption of the HE ration as a proportion of the total feed intake tended to increase as the experiment progressed. In spite of the differences in amount and pattern of feed consumption, the calculated total energy intake was similar in all groups. The only carcass measurements significantly affected by treatment were dressing percentage and backfat thickness; the possible implications of these effects are discussed.
GROWTH RETARDATION EFFECTS OF SOME GLUCOCORTICOIDS AND GLUCAGON IN CHICKENS
Authors: GAVORA J. S. , KONDRA P. A.
Published: March 2010

Three experiments were conducted to test the effects of Lipo-adrenal cortex (LAC), cortisone acetate (CA), hydrocortisone acetate (HCA) and glucagon (G) in broiler chickens. Oral administration of 38.7, 69.6 or 96.8 mg CA per bird significantly retarded body weight gain between days 14 and 21. HCA administered intramuscularly in doses varying from 2 to 24 mg/100 g of body weight significantly decreased body weight gain between days 14 and 28. Shank growth was similarly affected by doses over 4 mg HCA. The same doses significantly increased liver weight. At 3 months of age, birds recovered from growth retardation caused by the injection of 4 mg HCA/100 g of body weight at 14 days of age. Experimental results indicate that 2 or 4 mg HCA/100 g of body weight, administered by one injection at 14 days of age, may be used to increase growth rate variance by retarding growth.
GROWTH AND REPRODUCTION OF CHICKENS SUBJECTED TO MICROWAVE RADIATION
Authors: KONDRA P. A. , SMITH W. K. , HODGSON G. C. , BRAGG D. B. , GAVORA J. , HAMID M. A. K. , BOULANGER R. J.
Published: March 2010

White Leghorn hybrid chickens of different ages were subjected to CW microwave radiations at a frequency of 6 GHz and at densities of 0.02 and 400 picowatts/cm3. Microwaves were produced by a Varian LD 807 travelling wave tube. Continuous or periodic exposure of chickens during the growing stage did not affect their growth or feed conversion efficiency in comparison with non-treated controls. Hens subjected continuously, from 1 day old, to microwave treatment at the low or high densities showed significantly higher percent hen-day rate of lay, during 169 to 476 days of age, and significantly lower egg weight than the untreated birds. The low-density treatment resulted in significantly higher fertility than the high level of treatment. Egg quality, mortality and several other traits studied were unaffected by the treatments.
EFFECT OF MEDICATION WITH ANTIBIOTICS AND MATURE BOVINE PLASMA ON MORTALITY, MORBIDITY, RATE OF GROWTH AND SERUM IMMUNOGLOBULINS OF HOLSTEIN CALVES
Authors: LISTER E. E. , MacKAY R. R.
Published: March 2010

Nine of 18 Holstein calves, approximately one week of age, purchased at local auction, died when antibiotic therapy was withheld. Eighteen others receiving antibiotic therapy survived. Intravenous infusion of 250 ml of fresh bovine plasma within 24 hours of purchase resulted in improved viability in a third group of 18, but 500 ml infused intravenously in a fourth group of 18 resulted in viability little different from the group receiving no therapy. Calves given antibiotic treatment were more uniform in growth rate and efficiency of ration utilization than surviving calves on the other three treatments; in addition, they were more efficient than calves receiving no therapy. Serum "immunoglobulin" concentration at time of purchase was unrelated to subsequent mortality. However, mortality rate appeared to be inversely related chronologically to the general decrease and subsequent increase in serum "immunoglobulins".
RELATIVE MERIT OF THREE SWINE SELECTION PROGRAMS FOR THE SIMULTANEOUS IMPROVEMENT OF GROWTH RATE AND FEED EFFICIENCY
Authors: RAHNEFELD G. W.
Published: March 2010

Hypothetical swine populations with selection programs designed to capitalize on the favorable genetic correlation between growth rate and feed efficiency, and their heritabilities, are considered. Three types of selection programs are evaluated: plan A—selection for growth rate alone; plan B—selection for feed efficiency alone; and plan C—primary selection among litters for feed efficiency, coupled with secondary selection for growth rate. In the three programs, approximately 5% of the available boars and 25% of the available gilts are retained for breeding purposes. With the parameters selected, plan A will produce more genetic progress in growth rate than plan B or C, and plan B generally more than plan C. In the case of feed efficiency, selection under plan B consistently produces more genetic progress than plan A or C, and plan A generally more than plan C. Selection under plan A and plan B results in a greater amount of simultaneous genetic progress in the two traits than does plan C. In general, there is little to choose between plan A and plan B in the simultaneous genetic improvement of the two traits. The advantage of plan A over plan B is that growth rate can be measured with ease, and accuracy and testing facilities costs can be kept to a minimum.
INFLUENCE OF THE SIRE ON LITTER SIZE IN SWINE
Authors: RAHNEFELD G. W. , SWIERSTRA E. E.
Published: March 2010

The direct effect of the sire on the total number of pigs born (including stillborn, excluding necrotic), the number born alive, and the number weaned was studied in 277 Yorkshire and 356 Lacombe litters sired by 131 Yorkshire and 163 Lacombe boars. At mating, the average age of the males was 250 ± 18 days and of the females 248 ± 18 days. The Yorkshire and Lacombe sires produced an average of 2.11 and 2.18 litters, respectively. For the Yorkshire litters the total number of pigs born, number born alive, and number weaned were 9.43, 9.07, and 8.15, respectively. Corresponding averages for the Lacombes were 9.09, 8.38, and 6.97. In both the Yorkshire and Lacombe populations there was a significant sire effect on the total number of pigs born, the number born alive, and the number weaned. Intra-sire correlations (repeatability) for total number born, number born alive, and number weaned were 0.174 ± 0.082 (P < 0.05), 0.163 ± 0.081 (P < 0.05), 0.194 ± 0.081 (P < 0.01) in Yorkshires and 0.242 ± 0.070 (P < 0.01), 0.208 ± 0.071 (P < 0.01), and 0.167 ± 0.072 (P < 0.05) in Lacombes. Linear regression coefficients of litter size (number born, number born alive, number weaned) on number of females settled by the sire are presented.
MOISTURE CONTENT AND PROCESSING OF CORN FOR PIGS
Authors: YOUNG L. G.
Published: March 2010

Two trials were conducted involving 44 individually fed growing-finishing pigs to evaluate the effect of corn moisture content and method of processing of corn on performance. Digestible energy values of the diets were determined. When pigs had free access to feed and water, those fed high moisture corn consumed less dry matter and gained less rapidly than those fed artificially dried corn. The digestible energy values of diets containing whole corn were less than those of diets containing rolled or ground corn. The gain/feed ratio for diets containing whole corn was lower in the first trial but similar to other diets in the second trial.
EFFECT OF COPPER ON THE UTILIZATION OF RAW SOYBEANS BY MARKET PIGS
Authors: YOUNG L. G. , BROWN R. G. , SMITH G. C. , ASHTON G. C.
Published: March 2010

Three trials, involving a total of 160 Yorkshire SPF pigs, were conducted to evaluate the effect of the addition of copper (Cu) and/or raw ground soybeans (RGS) to diets of market pigs. The addition of RGS to pig diets resulted in decreased feed consumption and slower growth rate when pigs were fed ad libitum. When feed intake was restricted, rate of gain was not influenced by RGS. Dietary Cu supplementation resulted in an improved rate of gain and feed consumption when fed ad libitum, with a greater response exhibited by pigs fed diets containing RGS. Prediction of rate of gain for a constant feed intake suggested that a portion of the Cu effect is due to increased feed intake. Copper supplementation resulted in increased liver Cu, and decreased liver iron. Increased levels of dietary RGS resulted in decreased liver iron. An RGS × Cu interaction was observed in kidney Cu, in which higher dietary levels of both RGS and Cu were accompanied by decreased kidney Cu content. Increased levels of dietary RGS caused a decrease in nitrogen digestibility.
EFFECTS OF CONTINUOUS AND INTERMITTENT LIGHT ON BROILERS COLD STRESSED AS EMBRYOS
Authors: Buckland R. B. , Hill A. T.
Published: March 2010

not available
EFFECT OF BUNKER "C" OIL ON SHEEP
Authors: MacIntyre T. M.
Published: March 2010

not available
EQUIPMENT FOR THE CONTINUOUS SAMPLING OF EXPIRED C-14 CARBON DIOXIDE FROM ANIMALS IN A RESPIRATION CHAMBER
Authors: Cunningham H. M.
Published: March 2010

not available
SEED PRODUCTION OF PERENNIAL GRASSES IN THE GREENHOUSE
Authors: Knowles R. P.
Published: March 2010

Satisfactory seed production of several perennial grasses was obtained in the greenhouse in winter by using low temperatures and supplementary fluorescent lighting. Increasing light intensities from 400- to 800-foot candles approximately doubled seed production when lights were used for a 9-hour period. When lights were used for the entire day period of 17 hours, increasing light intensities from 500 to 750 f.c. or to 1,500 f.c. gave non-proportional increases in seed yields. Continuous lighting and 21-hour day lighting were not markedly better than 17-hour day lighting. Incandescent light of 400 f.c. was comparable to an equivalent intensity of fluorescent lighting in promoting seed production but incandescent lighting of 800 f.c. was inferior to 800 f.c fluorescent lighting.
STUDIES OF TOMATO RESPONSE TO MULCHING ON RIDGED AND FLAT ROWS
Authors: Chipman E. W.
Published: March 2010

Black plastic and sawdust mulches were applied to ridged and flat rows in a 2-year (1956–1957) study of their effect on tomato culture. Records were taken of soil temperature and moisture levels, ripe fruit to August 31, and total crop (ripe and green fruit).The highest early yield was obtained from the unmulched and sawdust plots but the heaviest total yield came from the black plastic plots. Highest soil temperature and lowest moisture readings were recorded under the black plastic, and lowest so 1 temperature and highest moisture under the sawdust.The earliest ripe fruits came from the flat rows, but the total crop was significantly higher on the ridge rows. There was no significant interaction for mulches and row type.
THE EFFECT OF SAWDUST, STRAW, COMPOST AND MANURE ON THE YIELD AND CHEMICAL COMPOSITION OF STRAWBERRIES AND ON SOIL MOISTURE, ACIDITY AND ORGANIC MATTER CONTENT
Authors: Webster G. R.
Published: March 2010

Sawdust, straw, compost and manure were applied under dryland conditions to strawberry plantings at two locations. The effects on yield, leaf nutrient content, soil moisture, soil acidity and soil organic matter content were evaluated. Sawdust mulch and sawdust incorporation, the former being slightly better, produced highly significant increased yields over the check treatment and were superior to all other treatments. Soil moisture measurements showed that the sawdust treatments conserved soil moisture and this was regarded as the chief reason for the increased yields. The nitrogen, phosphorus, potassium, calcium and magnesium contents of leaves were affected somewhat by the treatments but the levels were considered adequate in all cases.Soil acidity was significantly increased in the sawdust plots but this was attributed to the additional nitrogen applied rather than to the sawdust per se. Sawdust incorporation, manure and compost treatments significantly increased soil organic matter content when compared to the check treatment.
THE INFLUENCE OF CALCIUM AND MAGNESIUM SUPPLY ON NECTAR PRODUCTION IN RED CLOVER AND SNAPDRAGON
Authors: Shuel R. W.
Published: March 2010

The effect on nectar production of factorial combinations of three levels each of calcium and magnesium, comprising a ninefold variation in concentration, was studied in red clover and snapdragon. Plants were grown in sand and the essential elements supplied by daily sub-irrigation. Nectar secretion in red clover was comparatively sensitive to the availability of calcium and magnesium, the best factorial combination (intermediate calcium and high magnesium) producing almost twice as much nectar per unit of inflorescence weight as the poorest (low calcium and low magnesium). Nectar production was not correlated with vegetative growth or flower production. Inter-treatment variation was less extreme in snapdragon. In one crop the combination of high calcium and high magnesium, which supported the best growth and flower production, also gave the best nectar yield; in another crop the lowest level of calcium, sub-optimal for growth, produced the most nectar. The effects of nutrition on secretion were not related to the influence of pH, which was constant, or to the content of calcium, magnesium, nitrogen, phosphorus, or potassium in the red clover or snapdragon shoots.