bluuebunny/crossref_metadata_2025 huggingface dataset:
FISH PROTEIN CONCENTRATE (CONMAR 80) OR REFINED SOY FLOUR AS SUBSTITUTES FOR SKIM MILK POWDER IN CALF MILK REPLACERS
Authors: DEBOER H. , HACKER R. R. , LEESON S. , WAGEMANS V.
Published: March 2010

A new commercial hexane-extracted fish meal, Conmar 80, (80% CP) and soy flour were used as protein sources in milk replacer diets for young dairy calves. Three milk replacers, identical in composition except for the diet protein source, were offered in two experiments to Holstein Friesian male calves. The three treatments were: 50% skim milk (SM), 27% whey (W); 22% SM, 47% W, 9% Conmar 80; and 22% SM, 42% W, 15% soy flour. The first experiment compared calf performance parameters and a second experiment compared digestibility parameters for the three diets. A total of 132 Holstein calves were involved in trial 1 and 12 Holstein calves in trial 2. Calf performance, feed efficiency and mortality were not different from controls when Conmar 80 was included as a protein source (36%) in milk replacer. Partial replacement of skim milk powder with soy flour as 37% of the protein source gave lower average daily gains, a higher feed conversion and mortality rate. The digestibility data for all rations were similar. The results indicated that approximately one-third of the protein in milk replacer could be provided by fish protein concentrate in place of skim milk powder without any reduction in calf performance. Key words: Dairy calves, milk replacer, performance, Conmar 80
THE EFFECTS OF REPLACING SKIM MILK POWDER AND/OR WHEY WITH REFINED FISH PROTEIN CONCENTRATE (CONMAR 80) IN CREEP AND WEANER STARTER DIETS ON PIG PERFORMANCE
Authors: DEBOER H. , HACKER R. R. , LEESON S.
Published: March 2010

A series of trials was conducted to investigate the effects of Conmar 80 (80% CP), a new commercial hexane-extracted fish meal, as a protein source in creep and weaner-starter diets. Eight dietary treatments, comparable in composition except for the protein source, were offered in three experiments to 112 litters and 44 Yorkshire piglets. The first two trials were designed to compare piglet performance, during the suckling and early-weaning period when Conmar 80 was included as part of the creep diet or the starter diet protein. The third trial was designed to study the digestibility of increasing levels of Conmar 80 as a protein source in the weaner ration of 70-d old barrows. The results of this study indicate that piglet performance was not adversely affected when Conmar 80 was substituted at 3.5–5.0% of the creep diet or when Conmar 80 was used as the sole animal protein source in the starter diet. The digestibility of dry matter and crude protein was 85.6 ± 0.05% and 85.1 ± 0.24%; 74.7 ± 0.14% and 73.6 ± 0.53% when Conmar 80 was substituted in the weaner ration at the 5% and the 10% level respectively. The digestible energy was 13.5 ± 0.01 and 13.4 ± 0.04 MJ kg−1, respectively. It is concluded that Conmar 80 can satisfactorily be included to replace 14.5–22.0% of the dietary protein in pig creep and weaner feeds. Key words: Conmar 80, fish meal, swine, creep diets, weaner diets
UTILIZATION OF GRASS SILAGE BY CATTLE: FURTHER OBSERVATIONS ON THE EFFECT OF FISHMEAL
Authors: VEIRA D. M. , FORTIN A. , BUTLER G. , PROULX J. G.
Published: March 2010

Following weaning at 6–7 mo of age, 48 beef calves were used to determine growth response when two grass silages of contrasting nutritive value were supplemented with small amounts of barley or fishmeal. The silages were fed ad libitum for 112 d either alone or supplemented with 500 g barley or 500 g fishmeal per day. Both silages had similar cell wall and organic acid contents but silage 1 had higher nitrogen, 3.1 vs. 2.4% of dry matter (DM), and lower soluble sugar levels, 3.7 vs. 7.7% of DM, compared with silage 2. Animals fed silage 2 alone grew faster (P < 0.01) than calves fed silage 1 alone, 1.25 vs. 0.88 kg d−1. Supplementation with barley had no effect (P > 0.05) on liveweight gain; however, fishmeal substantially increased growth rate on both silages (P < 0.01), 0.49 and 0.3 kg d−1 for silages 1 and 2 respectively. Fishmeal tended to increase total DM intake of the silage 1 diet by an amount equivalent to the quantity of supplement offered but had no effect on DM intake of either silage (P > 0.05). Fishmeal supplementation also resulted in improved (P < 0.05) feed efficiency with both silages. Key words: Cattle, grass silage, fishmeal, growth
UTILIZATION OF CRAB MEAL FED TO YOUNG BEEF CATTLE
Authors: LAFLAMME L. F.
Published: March 2010

Two experiments were conducted to assess the nutritive value of crab meal for 200- and 300-kg weaned beef calves. In exp. 1, the addition of 10 or 20% soybean meal in a barley-based concentrate offered at up to 2 kg head−1 d−1 had a positive effect on growth rate and feed conversion efficiency of the 200-kg crossbred heifers fed hay ad libitum (P < 0.05). However, the incorporation of crab meal at levels of 15 and 35% of the concentrate mixture reduced (P < 0.05) feed consumption and growth. Levels of both 15 and 35% crab meal in the barley concentrate appeared to require an adaptation period by the heifers since feed intake and the weight gains improved with time. In exp. 2, steer calves weighing 200 or 300 kg were fed up to 1% of body weight of concentrate mixtures containing 20% soybean or 35% crab meal. Crab meal inclusion at 35% of the grain ration resulted in reduced feed intake and performance by the calves with most of this negative effect eliminated after a period of adaptation. Key words: Cattle, crab meal, grain, feed efficiency, soybean meal
IMPROVED FEEDING VALUE OF SASKATCHEWAN-GROWN BARLEY FOR BROILER CHICKENS WITH DIETARY ENZYME SUPPLEMENTATION
Authors: CLASSEN H. L. , CAMPBELL G. L. , GROOTWASSINK J. W. D.
Published: March 2010

Nine barley samples representative of cultivars grown throughout Saskatchewan were fed with dietary β-glucanase supplementation (Aspergillus niger) as mixed feed to broiler chickens. Experiment 1 compared barley diets with or without enzyme addition for broilers from 0 to 21 d, while exp. 2 involved comparison of broiler performance to market weight (0–42 d) when fed enzyme-supplemented barley diets or a wheat/corn-based diet. In exp. 1, chicks fed barley diets with the enzyme additive gained more weight and converted feed more efficiently than those given diets without the enzyme (P < 0.01). Variability among barley diets, as indicated by chick growth and feed efficiency, was reduced by the addition of the enzyme. In exp. 2, broilers consuming barley with dietary enzyme were lighter than their wheat/corn-fed counterparts at 21 and 42 d (P < 0.05). Body weight gain from 21 to 42 d was not significantly affected by dietary treatment. Feed-to-gain ratio was higher for barley-fed broilers (P < 0.05) in comparison to birds fed the wheat/corn diet, reflecting the lower nutrient density of the barley diets. Key words: Broiler chickens, barley, β-glucanase
SIMULTANEOUS ESTIMATION OF GENETIC PARAMETERS OF LIFETIME REPRODUCTIVE TRAITS IN MICE
Authors: NAGAI J. , LIN C. Y. , McALLISTER A. J.
Published: March 2010

Heritabilities and correlations between the length of reproductive life and number of parturitions during lifetime in mice were estimated from bivariate full-sib mixed-model analysis. Heritability estimates from sire components were low (0.01) for the two traits and those from dam components were slightly higher (0.06 and 0.05). Estimates of genetic and phenotypic correlations ranged from 0.89 to 0.99. It was concluded that the two traits are virtually the same trait biologically. Implication of these results for selection of lifetime production in mice and dairy cattle is discussed. Key words: Genetic parameters, reproductive trait, bivariate analysis
PRECISION OF SAMPLING TECHNIQUES IN DETERMINING MICROSCOPIC FOLLICULAR POPULATION IN GILTS
Authors: GRASSO F. , MATTON P. , DUFOUR J. J.
Published: March 2010

The precision of estimating populations of atretic and nonatretic antral follicles by sampling 10, 20 and 25% of follicles in serially sectioned ovaries was determined. From records on 18 374 gilt follicles (Data 1), three new data sets (Data 2, 3 and 4, generated by attributing a detection probability of 0.1, 0.2 and 0.25 to each of the follicles, were compared with Data 1. Estimates of the follicular populations obtained from Data 2, 3 or 4 differed from the values of Data 1 only when there were fewer than five follicles of a given size on the ovary. The coefficient of variation of the estimated numbers of follicles from values of Data 1 was below 32 ± 19% for Data 2 and 3 when there were more than 50 follicles in a class. For Data 4, however, it was 8 ± 2% or below except for classes containing less than five follicles. Data 4, but not Data 2 and 3, was as efficient as Data 1 in detecting differences in follicle distribution between breeds, age and type of ovary (P < 0.05), except for follicular classes containing less than five follicles. Thus, follicular populations, as determined by sampling 25% of the total number of follicles, were consistent with the actual distribution if five or more follicles were present in a class. Key words: Follicles, sampling, ovary, gilts
THE EFFECT OF GENOTYPE ON PREDICTED LEAN YIELD IN HEAVY PIG CARCASSES USING THE HENNESSY GRADING PROBE, THE DESTRON PG-100 AND THE FAT-O-MEATER ELECTRONIC GRADING PROBES
Authors: SATHER A. P. , JONES S. D. M. , ROBERTSON W. M.
Published: March 2010

One hundred and sixty-three carcasses from four genotypes (Lacombe, a halofhane-positive line, their F1 cross, and Yorkshire) at four weight classes ranging from 73 to 104 kg were evaluated by three electronic grade probes (Hennessy Grading Probe [HGP], Destron PG-100 [DGP]), Fat-O-Meater [FOM]). The two probes (HGP, DGP) in commercial use produced similar results for the prediction of lean yield. The carcass grading equations for the HGP and DGP were in close agreement with each other for predicted lean yield but they tended to increasingly underestimate the lean yield of carcasses as carcass weight increased. The halothane-positive line had predicted lean yields that were 4% less than actual, but pigs (i.e. Yorkshire) that are more typical of Canadian hog production still had predicted lean yield underestimated (1.5%), while predicted lean yield in the Lacombe was overestimated (1.1%). New prediction equations were developed which indicated no bias among the three probes, and were robust over a wide weight range. The addition of carcass weight reduced the residual standard deviation (RSD) for predicted lean yield from 1.913, 1.994 and 1.890 to 1.850, 1.875, and 1.797 for the HGP, DGP and FOM, respectively, while addition of a second probe site at the last rib further reduced the RSD to 1.725, 1.785 and 1.759. Furthermore the differences of the regression equations developed in the present study from those used by Agriculture Canada for grading hogs clearly illustrate the need to develop grading equations from animals that are representative of the population of pigs to be graded. Thus, there may be need to periodically reassess the grade probe equations as the genetic background changes or as carcass weight increases in the hog population. Key words: Electronic grading, market weight, genotype, halothane gene, Lacombe, Yorkshire
RATE AND EFFICIENCY OF GAIN IN HEREFORD AND ANGUS BULLS FROM LINES SELECTED FOR RAPID GROWTH ON HIGH-ENERGY AND LOW-ENERGY DIETS
Authors: BAILEY C. B. , LAWSON J. E.
Published: March 2010

Hereford and Angus bull calves were obtained from lines selected for an average of 18 yr for rapid growth on a high-energy diet (concentrate) or a low-energy diet (forage). They were given a typical feedlot diet (70% concentrate and 30% forage) in amounts about equal to 95% of the ad libitum intake and were slaughtered at a liveweight of 500 kg. Effects of breed, or of the selection diet given to the antecedents of the bulls, on rate and efficiency of gain of empty body, carcass, fat, protein, and energy were measured. Selection diet had no effect on rate or energetic efficiency of gain of the empty body or any of its constituents, nor on the distribution of the constituents of the gain between the carcass and the noncarcass portions of the empty body. This suggests that both selection diets exerted the same selection pressure for improved growth rate and feed efficiency when offspring resulting from selection were provided with a common high-energy diet and that either type of diet would, therefore, be appropriate for selecting animals for production systems that use high-energy diets. It was suggested that the main effect of selection was to increase the mature weight of the offspring. Comparing breeds, it was noted that Hereford bulls were heavier at birth, grew more slowly to weaning but more efficiently thereafter, and their carcasses were a smaller proportion of empty live weight than were those of Angus bulls. Key words: Diet, breed, growth, efficiency, selection, bull
CHEMICAL TREATMENT OF GROUND CORN TO LIMIT RUMINAL STARCH DIGESTION
Authors: FLUHARTY F. L. , LOERCH S. C.
Published: March 2010

Five trials were conducted to determine the effects of chemical treatment of ground corn on in vitro dry matter disappearance (IVDMD), in vivo nutrient utilization and ruminal starch digestion. Ground corn was treated with 0, 1, 2 or 3% (wt wt−1) formaldehyde, glyoxal, masonex, propionaldehyde or tannic acid. IVDMD of ground corn was inversely related (P < 0.01) to percent formaldehyde treatment level, while glyoxal, masonex, propionaldehyde and tannic acid were relatively ineffective in reducing IVDMD. Treatment of large batches of ground corn with 0, 0.5 or 1% (wt wt−1) formaldehyde also linearly reduced IVDMD (P < 0.01). Six abomasally fistulated wethers (average weight 95 kg) were used in a replicated 3 × 3 Latin square to determine the effects of 0, 1 or 2% (wt wt−1) formaldehyde treatment of ground corn on ruminal and total tract nutrient digestion. Ruminal dry matter (DM) digestion and total tract DM, organic matter (OM) and acid detergent fiber (ADF) digestion decreased linearly (P < 0.01) with increasing formaldehyde treatment levels. Ruminal starch digestion decreased 30% and 41.5% for 1 and 2% formaldehyde treatment, respectively, compared to untreated corn while total tract starch digestion was not affected (P > 0.05) by formaldehyde treatment level. Results of these trials are interpreted to suggest that formaldehyde treatment of ground corn reduced rumen microbial digestion of starch both in vitro and in vivo without reducing total tract starch digestion. Key words: Corn, starch digestion, formaldehyde, ruminants
TRUE ABSORPTION OF PHOSPHORUS IN SHEEP FED CORN SILAGE AND CORN SILAGE SUPPLEMENTED WITH DICALCIUM OR ROCK PHOSPHATE
Authors: DAYRELL M. de S. , IVAN M.
Published: March 2010

Eighteen male crossbred sheep were assigned to three groups and fed corn silage (CS), corn silage and dicalcium phosphate (CS-DP) or corn silage and rock phosphate (CS-RP). The rock phosphate originated from an igneous deposit located in Cargill Township in Northern Ontario. The endogenous fecal loss of phosphorus (P) was estimated by the isotope dilution method using 32P as a tracer. The total fecal P and total fecal endogenous P increased with increasing P intake. However, the percentage of endogenous fecal P was in the order: CS > CS-DP > CS-RP. The true absorption of P was 75.1, 67.3 and 48.1% for CS, CS-DP and CS-RP, respectively. The availability of P from rock phosphate supplement is much lower than that from dicalcium phosphate supplement. Key words: Sheep, phosphorus, true absorption, corn silage, dicalcium phosphate, rock phosphate
COMPARISON OF THE EFFECTS OF TOXIN-FREE AND TOXIN-CONTAINING MOLD-CONTAMINATED BARLEY ON CHICK PERFORMANCE
Authors: ROTTER R. G. , FROHLICH A. A. , MARQUARDT R. R. , ABRAMSON D.
Published: March 2010

Three chick (Single Comb White: Leghorn) growth trials were conducted using chemically characterized, toxin-free mold-contaminated barley samples naturally contaminated with Penicillium cyclopium and Aspergillus flavus fungi. The concentrations of fungal (mold) material in the samples, estimated by chemical analysis, ranged from about 1 to 16%. Compared to a mold-free barley control, the mold-contaminated barleys were generally higher in percent protein, ash and ADF, but had much lower bushel weights and percent fat and starch. The first trial compared the effects of feeding mold-free barley and 30% (wt/wt) of the 16% mold-contaminated barley in combination with 0, 2 and 4 ppm ochratoxin A (OA) on chick performance and nutrient digestion. Relative to controls, the average decreases in feed consumption (RFC) and weight gain (RWG) for birds fed the mold-contaminated barley were 50 and 80%, respectively. In contrast, 4 ppm of OA caused corresponding reductions of 22 and 30%, while in combination, mold and OA reduced performance slightly more than the mold alone. Similarly, apparent dry matter (DM), fat and protein digestibilities for birds fed mold-contaminated barley decreased 16.7, 37.7 and 13.7, respectively, compared to controls, but only 10.7, 21.5 and 12.0% for those fed 4 ppm OA. A second trial compared mold-contaminated barley samples from different sources with different degrees of contamination. Decreases in RFC and RWG were directly related (R2 = 0.96) to the mold concentration of the diet. The final study examined the effect on chick performance of incorporating increasing dietary concentrations of heavily contaminated (16% mold) mold-contaminated barley. As in trial 1, RFC and RWG were markedly affected by increasing dietary mold-contaminated barley. For example, the presence of only 15% (wt/wt) of the heavily contaminated mold-contaminated barley in the diet caused reductions of 20 and 30% in RFC and RWG, respectively. Apparent DM, fat and protein digestibilities again were all significantly (P < 0.0001) reduced by the mold. The results indicate the mold-contaminated barley can have a serious detrimental effect on chick performance, even when no toxins are detectable. Nutrient digestibility data suggest that antinutritive agent(s) in the mold-contaminated barley act to impair utilization of dietary nutrients rather than only those of the affected barley. Factors affecting diet palatability may also be involved. Key words: Mold, toxin-free, mycotoxin, ochratoxin A, barley, chick performance, apparent nutrient digestibility
ACCURACY OF SELECTION INDEX AND BEST LINEAR UNBIASED PREDICTION FOR WITHIN-HERD SELECTION WITH ASSORTATIVE MATING OF BEEF CATTLE
Authors: ROBINSON J. A. B. , WILTON J. W. , SCHAEFFER L. R.
Published: March 2010

A simulation of a selection and mating scheme for beef herds was conducted to compare the genetic progress achieved over 20 generations through evaluation of the animals by best linear unbiased prediction and by a selection index. For comparison, the same selection and mating scheme was applied to the herd using the true genetic values of each animal. Traits considered in the simulation were direct maternal genetic calving ease, birth weight, weaning weight and yearling weight. The analysis was replicated 100 times for each method of evaluation. In general, the best linear unbiased prediction system achieved greater genetic response than the selection index system. The BLUP system gave 18.7% better genetic improvement in total net worth than the selection index system. However, the selection index system gave only 42.7% and the BLUP system gave 50.6% of the response from selection on true net worth values. Keywords: Beef cattle, selection index, assortative mating.
THE EFFECT OF THE STRESS OF WEANING AND TRANSPORT ON WHITE BLOOD CELL PATTERNS AND FIBRINOGEN CONCENTRATION OF BEEF CALVES OF DIFFERENT GENOTYPES
Authors: PHILLIPS W. A. , JUNIEWICZ P. E. , ZAVY M. T. , TUNGELN D. L. VON
Published: March 2010

The response to the stressors of weaning and transport of four distinct genotypes of beef calves, kept under the same management and environmental conditions from conception to weaning, were measured to determine the effect of genotype on stress responses when all other factors associated with the farm of origin were held constant. Genotype had no effect (P > 0.10) on total leukocyte count during weaning, transport or during the post-transit period. Weaning resulted in a decrease (P < 0.05) in total leukocyte numbers, while transport increased (P < 0.05) the number of leukocytes. Fibrinogen concentration was highly variable among and within genotypes but in general, assembly and transit resulted in an increase (P < 0.05) in fibrinogen concentration. Bos indicus calves had higher (P < 0.05) concentrations of fibrinogen during weaning, assembly and transit. In conclusion, genotype of the calf did not alter the fibrinogen concentration, the number of leukocytes or the distribution of the leukocyte population as the result of weaning or transit. Key words: Cattle, stress, leukocyte, fibrinogen
FACTORS AFFECTING BEEF COLOR AT TIME OF GRADING
Authors: MURRAY A. C.
Published: March 2010

The color of the longissimus dorsi (LD) muscles from 7695 beef carcasses was evaluated following carcass grading at a commercial abattoir in the Central Alberta Region. Darker-than-normal beef was found in 3.7% of steer and heifer carcasses. However, the incidence of true dark-cutting beef (i.e., dark in color and with a pH greater than 6.0) was estimated to be only 0.5%. The length of time between stunning and the measurement of color had a major impact on color. The incidence of dark-colored beef was three times higher at 15–18 h than at 23–26 h poststunning, apparently because of incomplete development of muscle color at the earlier times. Carcass fat cover, weight and conformation affected muscle color, with smaller and leaner carcasses yielding higher frequency of dark-colored beef. Other factors influenced muscle color, including: (1) gender, (2) nutritional regime, (3) transit distance, (4) lairage time at the abattoir and (5) weather conditions. All of these could be explained by their effect on the time of color measurement or on carcass size and fatness. These findings indicate that if meat color is evaluated during the first 24 h postslaughter, it may be affected by many factors not related to preslaughter stress. During this time period accurate assessment of ultimate muscle color of the dark-cutting condition of conventionally-handled carcasses is not possible. Key words: Beef, color, dark cutting, stress
EFFECT OF MATURITY OF ALFALFA (Medicago sativa) AT HARVEST ON CALCIUM ABSORPTION IN GOATS
Authors: FREDEEN A. H.
Published: March 2010

Alfalfa hay harvested at vegetative or full bloom stages of maturity was compared to a control diet, in which the calcium (Ca) source was mainly limestone. True Ca absorption was determined using an isotope dilution technique in three goats fed Ca at requirement. Mean Ca intakes of goats fed the control, vegetative or full bloom alfalfa were: 2.40 ± 0.405, 2.31 ± 0.393 and 2.47 ± 0.461 g d−1; bone calcium accretion rates were: 1.27 ± 0.294, 0.90 ± 0.319 and 1.21 ± 0.237 g d−1; total Ca absorption rates (percent of intake) were: 57.1 ± 2.46, 56.7 ± 8.07 and 54.3 ± 3.03, respectively. Although no differences in true Ca absorption among diets were observed in goats fed Ca at requirement, absorption rates exceeded 50% of intake and are higher than previous estimates. Maturity of alfalfa did not significantly affect Ca availability, although there was a trend for availability to diminish with maturity when absorption rates were corrected for Ca absorbed from other dietary ingredients (i.e., 55.8% availability for vegetative, 47.0% for full-bloom alfalfa). Replacing limestone with alfalfa did not alter Ca bioavailability in the total diet. Key words: Goats, calcium true absorption, alfalfa, maturity, limestone.
AGRONOMIC AND CHEMICAL CHARACTERISTICS OF Kochia scoparia (L.) Schrad. AND ITS VALUE AS A SILAGE CROP FOR GROWING BEEF CATTLE
Authors: GRIMSON R. E. , STILBORN R. P. , VOLEK R. J. , GUMMESON P. K. , RIEMER G. E.
Published: March 2010

Kochia (Kochia scoparia (L.) Schrad.) was grown on land irrigated with packinghouse wastewater and ensiled in a plastic silo bag. Kochia dry matter (DM) yield and acid-detergent fiber (ADF), Na, Mg, Mn, and Cu contents (DM basis) were correlated with some soil measurements. Alfalfa silage was replaced with kochia silage in a basal diet at levels of one-half (35% of diet DM) or all (70% of diet DM) of the roughage. The diets were fed to 120 calves (initial weight 294 kg) for 70 d in a completely randomized experiment with three treatments (kochia, kochia and alfalfa, and alfalfa) and four pen replicates. Inclusion of either 35 or 70% kochia silage in the diet DM depressed (P < 0.01) DM intake (DMI) by 23.3 and 50.1%, respectively, compared with calves fed the basal diet. Average daily gain (ADG) and final bodyweight of the calves fed kochia silage were both less (P < 0.01) than those fed the basal diet. DM conversion to liveweight gain ratios (DM: G) were 13.91, 8.42, and 7.15 when the diets contained (DM basis) 70, 35, or 0% kochia silage, respectively. Over the 42-d period following the trial, the calves that had received kochia silage tended (P = 0.078) to gain faster than those that had been fed the basal diet. The reduction in DMI observed when kochia silage was fed appeared to be the result of advanced maturity and weather damage of the kochia and not due to apparent toxic effects. Key words: Kochia, silage, beef cattle, soil salinity
EFFECTS OF REDUCING DIETARY CATION-ANION BALANCE FOR PREPARTUM DAIRY COWS WITH SPECIFIC REFERENCE TO HYPOCALCEMIC PARTURIENT PARESIS
Authors: LECLERC HÉLÈNE , BLOCK ELLIOT
Published: March 2010

A trial was conducted to investigate the response of prepartum dairy cows to reducing the level of dietary cation-anion balance by measuring the concentration of plasma Ca, P, Mg and hydroxy proline, the apparent absorption of Ca, P and Mg and the incidence of milk fever. Twenty prepartum Holstein cows were randomly allocated to four dietary treatments designated control, diets 1, 2 and 3, with cation-anion balances [(Na + K) – (Cl + S)] of + 394, + 121, + 105 and + 62 meq kg−1 dietary dry matter (DM), respectively. Diets containing 1.38% Ca and 0.76% P (dry basis) were offered from day 45 prepartum to day 2 postpartum. Reducing the level of dietary cation-anion balance decreased the severity of the decline of plasma Ca during the periparturient period and delayed the time of observing the lowest concentration of plasma Ca. Strong negative correlations were observed during the periparturient period, particularly at parturition, between dietary cation-anion intake and the concentrations of plasma Ca and P. Apparent absorption of minerals was not influenced by dietary treatment from day 24 to day 21 prepartum. However, apparent absorption of Ca was reduced in cows fed diets 2 and 3 compared to cows fed the control diet and apparent absorption of Mg was reduced in cows fed diets 1, 2 and 3 compared to cows fed the control diet from day 7 prepartum until day 1 postpartum. Apparent absorption of phosphorus was not influenced by treatment at either time. Plasma levels of hydroxyproline were higher in cows fed diets 2 and 3 than in those fed diet 1 and the control diet from day 2 prepartum to day 1 postpartum. Results showed that reducing the level of dietary cation-anion balance influenced the concentration of plasma calcium, its apparent absorption and its resorption from bone. These effects were most accentuated during the periparturient period and may be beneficial in the prevention of milk fever. Key words: Milk fever, dairy cows, dietary anions and cations, parturient paresis
THE LONG-TERM EFFECTS OF FEEDING GROUND AND WHOLE COTTONSEED TO LAYING HENS
Authors: FITZSIMMONS R. C. , NEWCOMBE MARK , MOUL I. E.
Published: March 2010

Laying hens were fed diets containing 0, 2.5, 5, 10, 15 and 20% whole or ground cottonseed. Birds fed the 15 and 20% ground cottonseed diets rapidly reduced voluntary feed intake and, as a result, suffered a loss in both body weight and egg production. The severity of the dietary effects of cottonseed on productivity and mottled yolks was positively correlated with the level of cottonseed and gossypol in the diet. Egg yolk discoloration was assessed both visually on fresh yolks and using a time exposure to ammonia fumes. Discoloration was easier to detect using the ammonia test. In all cases, egg yolk discoloration was no longer apparent after a maximum of 42 d of feeding a commercial diet. Key words: Cottonseed, gossypol, laying hen, yolk mottling, egg production, feed intake
IN VITRO VISCOSITY MEASUREMENTS OF BARLEY EXTRACTS AS PREDICTORS OF GROWTH RESPONSES IN CHICKS FED BARLEY-BASED DIETS SUPPLEMENTED WITH A FUNGAL ENZYME PREPARATION
Authors: ROTTER B. A. , MARQUARDT R. R. , GUENTER W. , BILIADERIS C. , NEWMAN C. W.
Published: March 2010

The effects of in vitro extracting conditions on the viscosity of different barley cultivars were determined (exps. 1–3). Then, the relationship between three in vitro viscosity assays (method I, raw barley-HCl-KCl buffer; method II, autoclaved barley-H2O; and method III, raw barley-H2O) was compared with the performance of chicks fed barley-based diets supplemented with fungal enzyme (exp. 4). A significant three-way interaction (P < 0.0001) among fineness of grind, extraction method and barley cultivar showed that viscosity values for different barleys were not uniformly affected by the other two factors. Part of this differential response was eliminated by the use of finely ground barley (< 0.5-mm-mesh screen). When the three extracting methods were compared, method I gave higher readings than method II for high-viscosity barleys, and the reverse was true for low-viscosity barleys. The ranking of the barleys remained the same. Method III gave the lowest viscosity values, perhaps due to active endogenous β-glucanases in water extracts of the raw barley. When different barley cultivars were extracted by method I and subjected to different shear rates the viscosity differences were much more pronounced at the lower shear rates, particularly for high-viscosity barleys. Finally, the same seven barleys were compared in a feeding trial with chickens. The improvement in weight gain due to supplementation with a crude enzyme preparation from Trichoderma viride (Cellulase Tv) ranged from 2 to 41 % (P < 0.05). Similar improvements were obtained for feed consumption, feed-to-gain ratio and dry matter retention (P < 0.05). The highest simple correlation coefficients were between the viscosity of barleys that had been extracted by method I, measured at low shear rates, and relative weight gain (r = 0.97, week 1 plus week 2). The correlation coefficients using low shear rate data were slightly higher than those with high shear rate data. These results indicate that most pronounced differences among barleys were obtained with finely ground samples (<0.5 mm), extracted for one hour at 38 °C, using a low pH 1.5 buffer (method I) and assayed at low shear rates. Under these conditions the viscosity data reflected the antinutritive properties of barley, which in turn were reduced or abolished by adding a crude enzyme preparation to the diet. Key words: Viscosity, barley extracts, chicks, fungal enzyme
EFFECTS OF DIETARY SOURCES AND LEVELS OF FAT ON PERFORMANCE, NUTRIENT RETENTION AND BONE MINERALIZATION OF BROILER CHICKS FED TWO LEVELS OF CALCIUM
Authors: ATTEH J. O. , LEESON S. , SUMMERS J. D.
Published: March 2010

It is often reported that oil in full-fat seeds is poorly utilized by chicks. Studies were conducted to note the role of fat-mineral interactions for various oil and fat sources. The effects of dietary animal-vegetable blend fat (AV-blend), soybean oil, canola oil or canola soapstock at 5 or 10% inclusion level in the presence of low (0.8%) or high (1.2%) dietary calcium were investigated using broilers from 0 to 3 wk of age. Birds fed canola oil consumed significantly less feed than birds fed AV-blend fat (P < 0.05). Birds fed soybean oil exhibited a superior feed efficiency (P < 0.05). There was no effect of the dietary levels of fat or calcium on feed intake or feed efficiency (P > 0.05). There was no effect of the dietary treatments on protein retention (> 0.05). However, there was variation among the different sources of fat in their effects on fat retention and excreta soap concentration (P < 0.01). Significant interactions were observed between the dietary sources and levels of fat on calcium and magnesium retention (P < 0.01) and phosphorus retention (P < 0.05). There were also interactions between dietary sources of fat and calcium levels on magnesium and phosphorus retention (P < 0.05) while an interaction was observed between dietary levels of fat and calcium on the metabolizable energy values of the diets (P < 0.05). Birds fed diets with animal-vegetable blend fat had the lowest bone calcium content (P < 0.01). It is concluded from this trial that the problem of fat utilization often observed when full-fat protein supplements are fed to birds, relates to factors other than the type of fat they contain, since oils extracted from these full-fat protein supplements are well utilized. Key words: Fat, calcium, broiler performance, mineral metabolism
AMINO ACID SUPPLEMENTATION OF CANOLA MEAL
Authors: SUMMERS J. D. , BEDFORD M. , SPRATT D.
Published: March 2010

Supplementing a 15% protein diet for chickens, with all the protein coming from canola meal, with essential amino acids (EAA) to bring diet levels up to those recommended by NRC, failed to improve weight gain over that of an unsupplemented canola meal diet. While feed:gain ratio of the EAA-supplemented diet was improved, performance was markedly inferior to that of a 20% protein corn-soybean meal diet. Supplementing the canola meal basal diet with corn oil, lysine, or lysine plus arginine resulted in significant responses; however, performance was again far below that of the corn-soybean meal positive control diet. Supplementing the canola meal basal with EAA to bring levels up to close to the corn-soybean meal control diet resulted in performance which was superior to that obtained in the experiments in which EAA were supplemented to NRC requirement levels. However, performance was still markedly inferior to the corn-soybean meal control diet. A point of interest was the failure to demonstrate a need for methionine supplementation of the canola meal diet, even though by calculations it should have been deficient in this amino acid. A marked improvement in performance occurred when the level of methionine supplementation was reduced from 0.28 to 0.1% for the canola meal diet, supplemented with lysine, arginine and tryptophan. This clearly demonstrates that excess methionine or sulphur supplementation can markedly alter the performance of canola meal diets and may be one of the major reasons why EAA supplementation of semipurified diets that contain canola meal has failed to result in marked improvements in performance. Key words: Canola meal, amino acid supplementation, chickens
HIDE THICKNESS OF MARKET-WEIGHT SWINE AS AFFECTED BY LINE AND SEX
Authors: CLIPLEF R. L. , McKAY R. M.
Published: March 2010

Two hundred and eighty purebred boar and gilt carcasses, representing two genetic lines and 143 crossbred boars, barrows, and gilts were measured for hide thickness at three anatomical locations. A breed difference in hide thickness was apparent. Boars had thicker hides than gilts in the purebred carcasses and gilts and barrows in the crossbred carcasses. Gilt carcasses generally had thicker hides than barrow carcasses. Consistent location differences were evident in the purebred carcasses. Key words: Swine, carcasses, hides, skins, thickness, grading
THE NEUTROPHIL:LYMPHOCYTE RATIO IN PIGS FED CORTISOL
Authors: WIDOWSKI T. M. , CURTIS S. E. , GRAVES C. N.
Published: March 2010

In young pigs fed cortisol at 0, 25, 50, or 100 mg (kg diet)−1, the neutrophil:lymphocyte ratio (N:L) in smears of blood collected on days 1, 3, 5, and 7 increased with increasing cortisol concentration. On day 5, plasma total and dietary cortisol concentrations also were related directly. In controlled situations, an increase in N:L is one indicator of the pig's response to stress. Key words: Neutrophil:lymphocyte ratio, cortisol, stress indicator, pigs
REGIONAL HETEROGENEITY OF VARIANCES AND ITS EFFECT ON CANADIAN HOLSTEIN SIRE EVALUATION
Authors: SULLIVAN P. G. , SCHAEFFER L. R.
Published: March 2010

Heritabilities were estimated within each of four artificial insemination stud regions in Ontario and Quebec, based on a total of 880 329 records for milk and fat yield and 441 230 records for final class score. The pseudo-expectation (PE) and tilde-hat (TH) approaches were used. Estimates ranged from 0.32 to 0.46 for milk yield, from 0.31 to 0.53 for fat yield, and from 0.17 to 0.47 for final class score. Differences between methods (PE and TH) were as large as differences between regions for all traits. TH regional estimates were less variable than PE estimates. Changes in sire rankings were trivial when using regional estimates versus using a common variance ratio in each region during evaluation. Rank correlations were 0.98 and higher between evaluations based on heterogeneous regional variances and evaluations based on homogeneous variances. For all three traits, variance ratios that have previously been assumed for national evaluation were more appropriate than estimates obtained in this study. Use of the previously assumed values resulted in a greater consistency, measured by the correlation, between the regional proofs of a sire and between a sire's proof and pedigree index. Key words: Pseudo-expectation, tilde-hat, heterogeneous variances, Holstein, sire evaluation
INFLUENCE OF SUPPLEMENTATION ON FORAGE INTAKE AND NUTRIENT RETENTION OF GESTATING EWES GRAZING WINTER RANGE
Authors: HARRIS K. B. , THOMAS V. M. , PETERSEN M. K. , McINERNEY M. J. , KOTT R. W. , AYERS E.
Published: March 2010

Two studies, in 2 consecutive years, were conducted to determine the effects of supplementation on forage dry matter (DM) intake and nutrient retention (nutrient intake – nutrient loss in feces and urine) of gestating ewes grazing winter range. Sixteen ewes in each experiment were selected for uniformity in body weight and condition for random allotment to one of two treatments each year: no supplement (NS) and 0.15 kg head−1 d−1 pelleted barley-soybean meal supplement (S). Ewes were fitted with excreta collection bags and in year 1, four 96-h total fecal plus urine collection periods were conducted, while in year 2 three 96-h collection periods were used. Supplementation had no effect (P > 0.05) on forage DM or organic matter intakes in either year. Supplemented ewes retained more (P < 0.05) N and had increased (P < 0.05) differences between gross energy intakes and energy output in feces plus urine than NS ewes. Supplemented ewes retained more (P < 0.05) Mg, K, Mn, Cu and Zn in year 1 and K and Cu in year 2 than NS ewes. In summary, supplementation had no influence on forage DM intake but resulted in improved nutrient retention in gestating ewes grazing Montana winter range. Key words: Sheep, gestation, supplementation, forage intake, nutrient retention
RATE AND EFFICIENCY OF GAIN, FROM WEANING TO SLAUGHTER, OF STEERS GIVEN HAY, HAY SUPPLEMENTED WITH RUMTNAL UNDEGRADABLE PROTEIN, OR CONCENTRATE
Authors: BAILEY C. B.
Published: March 2010

Holstein steers were given milk from birth until they reached a weight of 100 kg. Beginning at 60 kg, they received gradually increasing amounts of one of three different diets and these became their sole diet after milk was withdrawn. The three diets were: (a) 85% grass hay and 15% concentrate (group 1); (b) the same diet with enough rumen undegradable protein (formaldehyde-treated canola meal) added to raise the crude protein content by 10 g kg−1 (group 2); and (c) 85% concentrate and 15% grass hay (group 3). The amounts of the three diets offered were designed to provide 0.95 MJ of digestible energy per day per unit of liveweight0.75. Steers were slaughtered at about 500 kg liveweight and the right sides of their carcasses were dissected into separable muscle, adipose tissue, and bone. This information was used to derive estimates of the daily gains of protein, fat, and energy in the empty bodies and the carcasses of the steers. Empty liveweight gain of group 3 steers exceeded that of group 1 steers by 42% and they required only 58% as much extra-maintenance energy per unit of gain. Daily gains of carcass muscle, adipose tissue, bone, protein, fat, and energy, and of empty body protein, fat, and energy, were greater in steers in group 3 than in those in group 1. The extra gain of group 3 steers, compared with group 1 steers, was due largely to gain of extra body fat. The overall efficiency of energy gain was 50% greater in steers in group 3 than in those in group 1. Supplementing the forage diet (group 1) with rumen undegradable protein (group 2) increased daily empty liveweight gains by 13% and reduced the extra-maintenance energy requirement per unit weight gain by 12%. Daily gains of carcass muscle, bone, and protein, and of empty body protein, were greater in steers in group 2 than in those in group 1. The extra gain of group 2 steers, compared with group 1 steers, was due largely to gain of extra body protein and its associated water. There were no differences between steers in these two groups in efficiency of energy gain (energy gain per unit extra-maintenance energy intake). It was concluded that the higher energetic efficiency of empty body weight gain of steers in group 2, as opposed to those in group 1, was due to a higher rate of net protein synthesis as a consequence of the increased amounts of protein absorbed from the intestine, and that the higher energetic efficiency of weight gain of steers given the concentrate diet (group 3), as opposed to those given the forage diet (group 1), was due to a higher efficiency of conversion of the energy-yielding products of digestion into fat. Key words: Energetic efficiency, steers, protein, undegradable, hay, concentrate
EVALUATION OF NAKED OATS (Avena nuda) AS A FEEDINGSTUFF FOR LAYING HENS
Authors: CAVE N. A. , HAMILTON R. M. G. , BURROWS V. D.
Published: March 2010

Two experiments were conducted with 640 and 480 White Leghorn strain-cross hens to determine the optimum level of inclusion of naked oats (Avena nuda L. 'Tibor') in diets fed for 51 wk. In exp. 1 oats from 2 crop years were substituted for corn and soybean meal at levels of 0, 300, 600 and 782 or 808 g kg−1 in isoenergetic and isolysinic diets. Egg yield (46.4 g d−1) and egg production (78.0% hen.day) were unchanged up to 600 g oats kg−1 but were 4 and 6% lower at the highest dietary levels due in part to a 4-d later sexual maturity. Egg weight was 2% greater in all oat diets than in the control diet. Feed utilized per gram egg was 4.7% lower at 600 g kg−1 than at 0 g oat kg−1 the other diets being intermediate. A difference between crop years was seen in a higher percent small grade eggs for 1985. Dietary treatments had no effect on feed utilized per egg laid, incidence of soft shell and cracked eggs or on final body weight. In exp. 2, naked oats with alfalfa meal and a vitamin-mineral premix were supplemented with canola meal or lysine plus methionine or not supplemented, to give dietary oat levels of 675, 874 and 876 g kg−1 for comparison with a control of 0 g kg−1. Supplementation with canola meal supported 3.5% higher egg yield and hen.day egg production than that with lysine plus methionine, whereas for both supplemented diets egg yield, hen.day percent egg production and egg weight, as indicated by distribution of eggs between size grades, were, respectively, 8, 6 and 1.7% greater and feed utilized per gram egg was 7% lower than for the supplemented naked oat diet. The corn-soy control diet differed from the amino-acid-supplemented diet only in a 4.9% greater feed utilization per gram egg. It was concluded that naked oats can replace corn and soybean meal in layer diets and that, with supplementation of canola meal or lysine plus methionine, oat levels up to, respectively, 675 and 874 g kg−1 diet can support satisfactory and efficient egg production. Key words: Oats naked, egg yield, egg weight, laying hen, canola
THE CHRONOBIOLOGICAL MANIPULATION OF TIME OF CALVING AND BEHAVIOR OF DAIRY CATTLE
Authors: EVANS N. M. , HACKER R. R.
Published: March 2010

Thirty-two cows in their 8th month of gestation were exposed daily to either 12–13 h of continuous light or to various skeletal photoperiods consisting of a total of 8 h of light. Cows in the skeletal photoperiod light regimens received 6 h of light from 05:00 to 11:00 h and a 2-h light pulse between 15:00 and 17:00 h, 18:00 and 20:00 h or 21:00 and 23:00 h (pulse 15:00–17:00 h, pulse 18:00–20:00 h or pulse 21:00–23:00 h, respectively). Time of calving was recorded for all cows. Behavior of cows in the respective treatments was monitored and time spent eating, standing or lying down and frequency of urination and defecation recorded. The light regimen of pulse 18:00–20:00 h was influential in restricting (P < 0.004) the randomness of time of calving. All cows in the pulse 18:00–20:00 h light regimen calved within the normal working hours of the barn (mean time of calving 1315 h ± 1.5 h). The mean time of calving for the control, pulse 15:00–17:00 h and pulse 21:00–23:00 h were 14:23 h, 12:56 h and 11:30 h, respectively (± 8.6, ± 6.36 and ± 9.53, respectively). The eating profile of the cows in the pulse 18:00–20:00 h group showed an additional peak of eating associated with the skeletal photoperiod. It is concluded that a circadian rhythm of parturition having a photosensitive phase is present in the dairy cow. This photosensitive phase occurs between 13 and 15 h after subjective dawn. Key words: Chronobiology, skeletal photoperiod, calving, behavior, circadian rhythm, dairy cattle
GROWTH PATTERNS OF RANGE BEEF CALVES OVER DISCRETE PREWEANING INTERVALS
Authors: HAVSTAD K. M. , McINERNEY M. J. , CHURCH S. B.
Published: March 2010

Suckling range beef calf production demonstrates periodicity despite consistency of management. Performance of calves within 33- to 50-d intervals from birth to weaning over nine seasons demonstrated maximum interval growth of approximately 1 kg d−1, but average seasonal growth rates varied from 0.79 to 0.99 kg d−1. Maximizing available forages for the final 33 d preweaning could minimize seasonal variations in calf production. Key words: Calf production, liveweight gain, rangelands
EFFECTS OF STORAGE CONDITIONS FOR LARGE ROUND BALES ON QUALITY OF GRASS-LEGUME HAY
Authors: LAFLAMME L. F.
Published: March 2010

Two experiments were conducted to assess the effects of storage conditions on the quality of large round bales (LRB). Samples were taken at 75-d intervals from LRB stored inside, outside single bales covered with a 15-mm black polyethylene plastic bag, outside uncovered as single bales, outside uncovered in a single row and outside uncovered in a double stacked row. Bales were sampled at depths of 0–15, 15–30 and 30–45 cm. Time, storage and depth factors had an influence on the chemical components of the LRB except for protein. Weathering had the most effect after 150 d of storage and with LRB stored uncovered and in the top 15-cm layer. Significant (P < 0.05) interactions in in vitro dry matter digestibilities were found for storage time × depth of sample, storage time × storage methods and for depth of sample × storage methods. Under the conditions of our experiments, weathering damages were limited to the superficial layer of LRB left uncovered. Key words: Large round bales, weathering, storage, moisture