bluuebunny/crossref_metadata_2025 huggingface dataset:
Feedlot performance, carcass composition and pork quality from entire male and female Landrace and Large White market-weight pigs
Authors: Sather A. P. , Jones S. D. M. , Joyal S.
Published: March 2010

A total of 80 pigs, representing Large White and Landrace boars and gilts were slaughtered at an average live weight of 92.3 kg (80.5 – 102.5 kg). Boars were housed in groups of five pigs per pen, and were individually fed to appetite twice daily for a period of 45 min. Gilts were housed in groups of 12 pigs per pen. The diet consisted of 21% crude protein with 3300 kcal kg−1 digestible energy. Carcasses were weighed on the slaughter floor and cooled at 1 °C for 24 h prior to dissection of the left side into fat, bone and lean. There were no significant breed-by-gender interactions for growth, carcass and meat quality traits. These pigs had low average backfat, when measured ultrasonically according to Canadian Swine Improvement Program standards on the live pig (gilts 12.3 mm, boars 10.1 mm), high average daily gain (ADG: gilts 880, boars 940 g d−1) and low age adjusted to 90 kg (gilts 148, boars 145 d). Large White boars had a lower feed conversion ratio (2.18 vs. 2.32, P = 0.015) and less feed intake per day (2.05 vs. 2.14 kg d−1P = 0.020) than did Landrace boars. There were no significant differences in dissected lean yield between breeds (P = 0.389) or genders (P = 0.148). However, gilts had greater carcass grade fat and greater lean depth measurements than did boars, such that both genders had a predicted lean yield of 51.8%. Gilts (40.8 cm2) had a larger (P < 0.001) longissimus dorsi area than boars (38.0 cm2). There were no breed effects on the lean content of the four major cuts (P = 0.20), but boars had less fat (P = 0.01) and more bone than gilts (P < 0.01). There were few consistent differences in subjective or objective meat quality traits (i.e. color, drip loss) among breeds or genders. Boars had muscle with greater moisture than gilts (P < 0.001) as well as softer fat (P = 0.016). Thus, it appears possible to produce pork of high quality from lean animals and that lean boars efficiently produce carcasses of equivalent yield and quality to carcasses produced by lean gilts. Key words: Swine, boar, carcass composition, meat quality, Landrace, Large White
Teat stimulation and milk production during early lactation in sows: Effects of continuous noise
Authors: Algers Bo , Jensen Per
Published: March 2010

The aim of the study was to investigate if the time or the intensity of the massage performed after let down by suckling piglets influenced the amount of milk produced by the teat receiving the massage and to study if the effects of continuous fan noise affected piglet milk consumption. Twelve Swedish Landrace × Yorkshire sows, six of them exposed to continuous fan noise, were studied together with their litters. On days 1–3 postfarrowing, the number of massage movements and the time each piglet was massaging was recorded in relation to milk letdown. The teat used by each piglet was noted and whether the piglet was urinating or defecating during the suckling. Piglets were weighed before and after each suckling and on days 7 and 14. The duration and intensity of teat stimulation given to a teat influenced the production of that teat during the first days of lactation in sows not exposed to noise. There was a tendency for the 3rd and 4th teat-pairs to respond less to the massage than the front or rear teat-pairs. Suckling piglets subjected to continuous loud noise performed less teat stimulation and the milk production of the sow was less. Key words: Pig, lactation, nursing, suckling, milk production
Cutting frequency and cutting height effects on forage quality of rough fescue and Parry oat grass
Authors: Willms W. D. , Beauchemin K. A.
Published: March 2010

An experiment was conducted to determine the qualitative response of rough fescue (Festuca scabrella var. campestris) and Parry oat grass (Danthonia parryi) to five cutting frequencies and three cutting heights Beginning in mid-May, the same plants were cut every 1, 2, 4, 8, or 16 wk. during a 16-wk period, at heights of either 5, 10, or 15 cm above ground level. The treatments were repeated in 3 consecutive years on the same plants. Crude protein (CP), lignin, and calcium (Ca) were significantly greater for Parry oat grass than for rough fescue, which had greater acid detergent fiber (ADF) and phosphorus (P) concentrations. Increasing cutting frequency in the first year reduced acid detergent-insoluble nitrogen (ADIN), ADF, and lignin but increased CP and in vitro digestibility of dry matter (IVD) in both forages. Repeated treatment over 3 yr tended lo increase ADF and Ca but reduce CP, P, and IVD. In the first year of treatment, CP yields in rough fescue and Parry oat grass were greatest with 2 or 4 cuts during the growing season. However, in the second year of treatment, CP yield was greatest with one or two cuts in rough fescue and with four cuts in Parry oat grass. The data confirm the benefits of repeated grazing within a year to maintain high quality forage but demonstrate the need to limit the frequency of repeated grazing to avoid deterioration and maximize nutrient yield. Nutrient yields and, presumably, benefits to livestock would be greater at a lower grazing frequency on rough fescue than on Parry oat grass. Key words: Festuca scabrella var. campestris, Danthonia parryi, crude protein, acid detergent fiber, in vitro digestibility, forage quality
Nutritive value of kochia (Kochia scoparia) hay or silage grown in a Black soil zone in northeastern Saskatchewan for sheep
Authors: Mir Z. , Bittman S. , Townley-Smith L.
Published: March 2010

Two trials were conducted to evaluate the voluntary intake and digestibility of kochia (Kochia scoparia) as hay or silage for sheep. In Trial 1, kochia (KOC) hay substituted for alfalfa hay (AA) at 0, 25, 50 or 75% of complete diets, or 50% AA or 50% KOC with barley (BAR) were fed to 24 mature wethers in a completely randomized design experiment. As the level of KOC in the diet increased, dry matter intake (DMI) of wethers decreased linearly. There were no differences (P > 0.05) in dry matter or fiber digestibilities among the four diets containing AA and KOC hay. Nitrogen and gross energy digestibilities increased linearly (P < 0.05) with decreasing levels of dietary KOC. In trial 2, KOC silage prepared from two ecotypes of KOC (southern and northern), cut at two different dates and fed in a 50:50 combination with AA silage were compared with a diet containing AA silage. DMI and nutrient digestibilities of the AA silage diet were higher (P < 0.05) than those for the diets containing KOC. Results indicate that KOC hay can be fed in high forage or concentrate diets at levels between 25 and 50% of the diet without adverse effects on intake or digestibility. Results also demonstrate that KOC can be preserved by ensiling and that KOC silage can be used in combination with AA silage in diets for sheep. Key words: Kochia, sheep, digestibility, hay, silage
Evaluation of the quality of ground water supplies used on Saskatchewan swine farms
Authors: McLeese J. M. , Patience J. F. , Christison G. I. , Wolynetz M. S.
Published: March 2010

An extensive survey of well water used on swine farms in Saskatchewan was undertaken as a first step in trying to clarify the apparent disagreement between field and laboratory observations with respect to water quality and pig performance. One hundred and thirty-five wells throughout the province were sampled for a comprehensive chemical analysis; at the same time, a questionnaire concerning pig performance and perceptions of water quality was administered to the well owners. Concentrations of sulphate and total dissolved solids (TDS) were above levels recommended in Canada for livestock in 25.0% and 7.4%, respectively, of the wells. Sodium and chloride were also high in many wells. High levels of trace metals were not observed. Three major groups of wells were discerned: low saline, shallow wells with sulphate being the major contributor to TDS, high saline, deeper wells, also with sulphate being the major contributor to TDS, and high saline, deep wells with sodium the major contributor to TDS. The incidence of minor to moderate scouring in weanlings, as reported by producers, was directly related to TDS, magnesium, calcium and sulphate, but bore no relationship to sodium. The common occurrence of high sulphate water and its apparent link to on-farm scouring in weanlings indicate that sulphate is probably the ion of most concern to Saskatchewan hog producers. Key words: Well water quality, swine, sulphate, scouring
Discovery of selected water dispensers by newborn pigs
Authors: Phillips P. A. , Fraser D.
Published: March 2010

Newborn pigs in 86 litters were offered drinking water from four types of dispenser to determine how quickly each design would be discovered. On average piglets discovered water within about 24 h from an exposed water surface (bowl or cup), whereas discovery time was delayed to more than 72 h with nipple or push-lever dispensers. A prototype dispenser with a wide bowl and continuous bubbling action reduced (P < 0.05) average discovery time to about 14 h. Key words: Piglet, water, dispenser design
The effect of age and method of castration on plasma cortisol in beef calves
Authors: King B. D. , Cohen R. D. H. , Guenther C. L. , Janzen E. D.
Published: March 2010

Plasma cortisol concentration (PCC) was measured at 0, 2 min, 3, 6, 12, 24 and 30 h in 36 calves castrated at 78 ± 12 d of age or 167 ± 14 d of age by either surgical or burdizzo methods or left as bulls (control). At 2 min, bull calves had greater (P < 0.05) PCC (22.2 ± 4.5 μg L−1) than burdizzo castrates (10.4 ± 3.0 μg L−1) while surgical castrates were intermediate and not different (P > 0.05) from either group (11.4 ± 2.9 μg L−1). There were no further differences between groups until the 30 h postcastration bleed when PCC for bull calves (22.1 ± 6.0 μg L−1) was greater (P < 0.05) than surgical (7.4 ± 2.3 μg L−1) and burdizzo (9.5 ± 2.4 μg L−1) castrates. At late castration, there was an immediate rise in PCC 2 min postcastration for burdizzo castrates (32.0 ± 3.1 μg L−1) which was greater (P < 0.05) than surgical castrates (18.6 ± 4.1 μg L−1), while bull calves (23.0 ± 1.9 μg L−1) were intermediate and not different from either castration group. At 3 h, PCC of surgical (44.4 ± 4.2 μg L−1) and burdizzo (38.6 ± 8.3 μg L−1) castrates was greater (P < 0.05) than bull calves (24.1 ± 8.5 μg L−1). At 6 h, surgical castrates had a greater (P < 0.05) PCC (27.5 ± 5.4 μg L−1) than burdizzo castrates (15.3 ± 0.41 μg L−1) but neither group was different (P > 0.05) from bull calves (17.2 ± 2.7 μg L−1). There were no further differences between groups up to 30 h postcastration. It was concluded that castration at a young age caused no physiologically detectable stress while physiological stress was detectable in older calves but that, in older calves, burdizzo was less stressful than surgical castration. Average daily weight gain did not differ (P > 0.05) between castrated and bull calves. Key words: Castration, plasma cortisol, age, beef calves
Effect of postweaning implantation of zeranol and dietary energy level on growth and reproductive performance of replacement beef heifers
Authors: Makarechian M. , Arthur P. F. , Price M. A.
Published: March 2010

Eighty-one heifer calves weaned at an average age of 6 mo were used to study the effect of postweaning zeranol implantation, on the growth and reproductive performance of heifers fed to grow slowly on three dietary energy levels. Forty heifers were implanted with 36 mg of zeranol at 30 d and again at 120 d postweaning. The remaining heifers were used as ummplanted controls. Within the implanted and control groups, heifers were subdivided into three groups and fed either a low, medium or high energy diet, which provided approximately 105, 130 and 160%, respectively, of NRC maintenance energy requirement, until 1 yr of age. The heifers were then turned out to pasture with hay supplementation. Heifers were exposed to bulls for 35 d at approximately 14 mo of age. Zeranol had no significant effect on growth. The effect of zeranol on the reproductive traits studied was not significant, although the trend was that the zeranol implanted heifers had lower calf crop born (52.3 vs. 63.6%) and lower incidence of calving difficulty (18.5 vs. 32.1%) than control heifers. The level of energy in the diet had a significant (P < 0.01) effect on growth of the heifers, with those on the high energy diet having the highest mean growth rate, but no significant effect on reproductive performance. Key words: Zeranol, dietary energy, growth, reproduction, heifers
Comparison of genetic and phenotypic parameters in a purebred and a synthetic beef cattle population
Authors: Liu M. F. , Makarechian M. , Berg R. T.
Published: March 2010

Genetic and phenotypic parameters of growth traits from birth to 1 year of age were compared in a multibreed Beef Synthetic (SY) and a purebred Hereford (HE) population managed together under the same environmental conditions and selected for growth rate from 1961 to 1979. Growth traits studied were birth weight, preweaning and postweaning gains. Records of 2077 calves of 70 HE and 100 SY paternal half-sib families were used for analysis. Except for birth weight, phenotypic variances of growth traits were similar for the synthetic (SY) and purebred (HE) populations, but genetic variances were larger in SY than in HE for all growth traits except postweaning gain in males. The coefficients of variation were comparable for all the traits studied in the two populations, indicating that phenotypic variations in the multibreed population and the purebred population were similar. Key words: Variance components, heritability, beef cattle
The effect of castration age, method and implant regime on growth and carcass traits of male beef cattle
Authors: Cohen R. D. H. , King B. D. , Nicholson H. H. , Janzen E. D.
Published: March 2010

In 1984–1985 and 1985–1986 groups of 136 and 127 male calves were used to assess the effects of multiple implants (Ralgro and Steeroid), castration time (early and late) and castration method (surgical and chemical) on growth to weaning and feedlot performance and carcass characteristics. Ralgro increased calf rate of gain to weaning (P < 0.05) and adjusted weaning weight (P < 0.01) but did not affect rate of gain during the feedlot period. Although Ralgro increased (P < 0.001) weight at slaughter, it took longer (P < 0.05) for implanted cattle to reach Canada A1 than unimplanted cattle. Steeroid did not affect rate of gain to weaning but did increase (P < 0.05) adjusted weaning weight. Steeroid increased (P < 0.05) rate of gain relative to unimplanted cattle during the growing period in the feedlot and cattle implanted four times from birth to slaughter gained more (P < 0.05) than cattle implanted twice (birth and weaning). For the entire feedlot period, bulls receiving Steeroid gained faster (P < 0.05) than unimplanted bulls with no difference (P > 0.05) between implant groups (two or four implants). Ralgro implants increased (P < 0.05) carcass weight, rib-eye area and cutability while Steeroid increased (P < 0.05) only carcass weight. However, when rib-eye area was adjusted for carcass weight, the effect of Ralgro was not significant (P > 0.05). Bulls had greater (P < 0.05) shipping weight, carcass weight, rib-eye area, dressing percent and cutability than steers. Age at castration (early or late) had no effect on feedlot performance or carcass traits while method of castration (surgical or chemical) had some effects (P < 0.05) on ADG, liveweight, carcass weight and rib-eye area. Key words: Castration, Ralgro, Steeroid, beef, growth, carcass
Effects of recombinant bovine somatotropin on hypophyseal and ovarian functions of lactating dairy cows
Authors: Gallo Guillermo F. , Block Elliot
Published: March 2010

Three trials were conducted to determine the effects of recombinant bovine somatotropin (rbST) on reproductive functions of lactating Holstein dairy cows. In Trial 1, 49 cows were used to investigate the effects of 0, 320 or 640 mg of rbST in a sustained-release formulation injected every 28 d on plasma progesterone (P4) concentration during estrous cycles. Total P4 area and P4 mean were increased (P < 0.05) in rbST-treated cows during the 1st and 2nd detected estrous cycle post-rbST injection. Maximum P4 value, slope of the P4 decline and length of cycles were not affected by rbST treatment. In Trial 2, 56 cows were used to investigate the effects of 0, 320, 640 and 960 mg of rbST in a sustained-release preparation injected every 28 d on plasma P4 concentration from weeks 1 to 34 of pregnancy. Mean P4 was increased (P = 0.08) in rbST-treated cows proportionally to the rbST dose received. In Trial 3, 18 cows were used to investigate the effects of 0 or 25 mg d−1 of rbST injected from days 3 to 15 postpartum (pp) on the gonadotropin-releasing hormone (GnRH) induced luteinizing hormone (LH) response curve at 14 d pp. Total area under the LH curve and LH peak value were increased (P < 0.05) in rbST-treated cows, but LH baseline and time to LH peak were not different among groups. Cows receiving rbST were in a more negative energy balance due to higher milk production. In summary, long-term administration of rbST increased the concentration of plasma progesterone during the first two estrous cycles post-treatment and during pregnancy, and enhanced the GnRH-induced LH response at 14 d pp. Key words: Bovine somatotropin, GnRH-LH induction, progesterone, estrous cycle, pregnancy
Intake and digestibility of alkaline hydrogen peroxide-treated wheat straw-alfalfa hay combinations fed to sheep
Authors: Atwell D. G. , Merchen N. R. , Jaster E. H. , Fahey Jr. G. C. , Berger L. L.
Published: March 2010

A 5 × 5 Latin square experiment utilizing mature wethers (78 kg) was conducted to investigate the effects of feeding combinations of alkaline hydrogen peroxide-treated wheat straw (AHP-WS) and alfalfa hay on intake and nutrient digestibility. Diets consisted of an 80:20 forage to concentrate ratio on a dry matter (DM) basis. Dietary designations were based on ratios of AHP-WS: alfalfa hay in the diet. Quadratic responses (P < 0.05) were noted for both DM intake (DMI) as a percentage of body weight and organic matter intake (OMI) expressed as g d−1. Greater DMI and OMI were noted when wethers were fed diets containing combinations of AHP-WS and alfalfa (40:40 and 20:60) than when fed those containing AHP-WS or alfalfa as the sole forage (80:0 or 0:80). No effects of diet on digestibilities of dietary components were observed, with digestibility of DM and OM averaging 67 and 69%, respectively, across diets. Wethers consumed greater amounts of digestible OM when fed combinations of the two forages than when either was fed alone. Molar proportions of all ruminal volatile fatty acids (VFA) except acetate responded in a quadratic (P < 0.05) manner due to diet. Molar proportion of propionate decreased while molar proportions of other VFA increased with increasing level of alfalfa. Ruminal liquid and particulate dilution rates were not affected by diet. Time spent ruminating by sheep was increased linearly (P < 0.05) by inclusion of alfalfa hay in the diet. Favorable comparisons of AHP-WS to high quality alfalfa hay demonstrate the effectiveness of the AHP treatment process to enhance the nutritive value of WS. Key words: Intake, digestibility, treated wheat straw, alfalfa, sheep
Influence of source of rumen-degraded nitrogen on ruminal and whole tract digestion, plasma hormone and metabolite concentrations as well as milk yield and composition in dairy cows
Authors: Robinson P. H. , Boer G. de , Kennelly J. J.
Published: March 2010

Fifteen multiparous and 10 primiparous cows in early lactation (parturition through 16 wk postpartum inclusive) were fed one of five totally mixed diets. Diets differed in the source of supplemental nitrogen with isonitrogenous substitution of canola meal (a rapidly rumen-degraded true protein source) by Barlein (a rapidly rumen degraded nonprotein nitrogen source). All diets were 40% whole crop oat silage and 60% concentrate on a dry matter basis. Rumen pH, ammonia N and lactate concentrations as well as in sacco rumen degradability of whole diet nitrogen were not influenced by treatment. These results appear to support the assumption that Barlein nitrogen was released in the rumen at a rate similar to that of canola meal protein. Feed intake and body weight change did not differ among treatments. However, milk yield declined linearly as substitution of canola meal with Barlein increased. Milk composition of fat, protein, and lactose were not influenced by treatment although milk urea concentrations increased as substitution of canola meal with Barlein increased. Data collected did not conclusively identify the mechanism for the reduced performance; however, it seems most likely it was the result of reduced rumen microbial growth and escape as substitution of canola meal with Barlein increased, leading to a deficiency in metabolizable protein supply. Key words: NPN, dairy cattle, protein
Preservation of high-moisture hay in storage through the use of forage additives
Authors: Wittenberg K. M.
Published: March 2010

Two inoculants, a buffered propionic acid formulation and anhydrous ammonia were compared for use as hay preservatives. Alfalfa forage was baled at three moisture levels: 15–20%, identified as low (L); 20–25%, identified as medium (M); 25–30% identified as high (H). Hay baled at the M and H moisture levels was treated with no forage additive (Con); anhydrous ammonia (NH3) applied to forage placed in the stack; buffered propionic acid (63% acid, Acid); two strains of Pediococcus pentosaceus (A) or a mixture of Pediococcus acidilactici and Lactobacillus plantarum (B) applied at the time of baling. Due to precipitation (34.1 mm), hay baled at the L moisture level had greater (P < 0.05) acid detergent fiber (ADF), acid insoluble nitrogen and chitin levels at the time of stacking than hay baled at M and H moisture levels. Storage conditions for hay baled at the M moisture level resulted in high dry matter (DM), crude protein (CP) and ADF retention and relatively moderate increases in chitin levels during storage for all treatments. Storage of hay baled at the H moisture level without use of a forage additive resulted in poor DM and nutrient retention, and marked increases in chitin concentrations during the storage period. H-NH3 and H-B improved (P < 0.05) DM, CP and ADF retention relative to H-Con. H-Acid improved (P < 0.05) CP retention whereas H-A had no positive effect on DM and nutrient retention. All forage additives improved (P < 0.05) the visual assessment of H moisture bales for mold and dust relative to H-Con; however, extent of fungal invasion as measured by chitin analysis was not reduced with the use of forage additive. Key words: Anhydrous ammonia, propionic acid, bacterial inoculants, hay preservation
Effect of ammoniation on the preservation and feeding value of barley grain for growing-finishing cattle
Authors: Yaremcio B. J. , Engstrom D. F. , Mathison G. W. , Caine W. R. , Roth L. A.
Published: March 2010

Two on-farm feed storage trials, a steer feeding trial and a digestibility trial were conducted to determine the effectiveness of anhydrous ammonia as a grain preservative and to examine its influence on the nutritive value of the grain. In exp. 1, on Farm A anhydrous ammonia was added to barley (85% dry matter (DM)) at concentrations of 0.6 or 0.9% and to barley containing 78% DM at concentrations of 3.6 and 5.0% (DM basis). Both lots of the 78% DM barley spoiled. On farm B, barley grain averaging 80% DM and treated with 2.1–3.8% ammonia was preserved whether stored in open or covered bins. In exp. 2, 160 steers were fed diets containing 88% DM barley, 80% DM barley, 83% DM ammonia-treated barley, 72% DM barley, or 75% DM ammonia-treated barley. The barley was either fed whole or rolled. No differences (P > 0.05) due to ammoniation were detected in daily gain, feed efficiency and carcass composition. However, steers fed whole barley required 15% more (P < 0.05) DM per unit gain than those fed rolled barley and had a 7% numerical decrease (P = 0.11) in gain. Supplemental thiamin and vitamin E had no influence (P > 0.05) on animal gains or feed efficiency. The digestibility of diets containing ammoniated barley was reduced (P < 0.01) 8–9 percentage units by feeding whole barley as compared to rolled. Grain processing had no influence on energy losses as methane or heat or on energy retention. It was concluded that anhydrous ammonia is not an effective preservative under some aerobic conditions, the feeding value of barley was not influenced by ammoniation, and vitamin E and thiamin supplementation of diets containing high-moisture grain may not be warranted. Key words: High-moisture barley, steers, preservation, ammonia, thiamin, vitamin E
Effect of alfalfa grass silage dry matter content on ruminal digestion and milk production in lactating dairy cows
Authors: Campbell C. P. , Buchanan-Smith J. G.
Published: March 2010

In trial one, seven lactating Holstein cows fitted with rumen cannulae were used in a replicated 3 × 3 Latin square design to investigate the effect of feeding alfalfa/grass ensiled at three dry matter (DM) levels (27.5, 46.1 and 56.4%) on the rate and extent of protein degradation. Cows were fed a total mixed ration of 70% alfalfa/grass silage, at one of three DM levels, and 30% concentrate (high moisture corn and mineral) (DM basis). Silage samples were incubated in sacco in the rumen for up to 48 h to model disappearance of DM, neutral detergent fibre (NDF) and nitrogen (N). Passage rates of silage, using Cr-mordanted NDF, were determined for small and total particulate fractions. Rates of DM, NDF and N disappearance, as well as rates of passage were unaffected by silage DM content. The 27% DM silage contained a larger soluble N fraction, but a smaller fraction of potentially digestible N than either the 46 or 56% DM silages. Estimates of effective protein degradability corrected for microbial contamination of digesta residues, for the 27, 46 and 56% DM silages were 75.8, 71.2 and 65.0%, respectively. In a second trial, 30 Holstein cows in mid-lactation were fed the same silages as in trial 1 using a completely randomized design. Milk protein percent and yield were higher (P < 0.05) for cows fed the 56% DM silage than those fed the 27 or 46% DM silages. Wilting alfalfa/grass silages prior to ensiling decreased estimated net ruminal silage protein degradation, which was associated with improved milk protein yield. Key words: Alfalfa silage, dry matter, protein, degradability, dairy cow
Replacing skimmed milk powder by oat protein concentrate in milk replacers for piglets
Authors: Delisle J. , Bernier J. F. , Brisson G. J.
Published: March 2010

Two experiments were conducted with 24- to 72-h-old male piglets. In exp. 1, 24 piglets were assigned to three dietary treatments. In the control diet, 100% of the dietary protein originated from low-heat skimmed milk powder. In the other diets, either 25 or 50% of the milk proteins were replaced by oat protein concentrate. In exp. 2, eight piglets were assigned to each of two diets where 100% of the dietary protein originated from skimmed milk powder and 50% of the milk proteins were replaced by oat protein concentrate. In exp. 1, dry matter intake was not affected by treatments while body weight gain declined and feed to gain ratio increased significantly (P < 0.05) when oat protein concentrate replaced 50% of the milk proteins. Similar observations were made in exp. 2 regarding dry matter intake, body weight gain and feed gain ratio although digestibility of dry matter and nitrogen was the same (P > 0.05) for both the oat and milk protein treatments. Oat protein concentrate can thus replace up to 50% of milk proteins without apparent detrimental effect on dry matter intake and N digestibility; however, growth rate will be reduced. Key words: Piglets, artificial rearing, milk replacer, skimmed milk powder, oat protein concentrate, digestibility
Reproductive performance, growth rate and body composition of full-fed versus feed-restricted broiler breeder hens
Authors: Robinson F. E. , Robinson N. A. , Scott T. A.
Published: March 2010

The effects of ad libitum versus restricted feeding during the period from 22 to 62 wk of age were examined in 60 individually-housed Indian River broiler breeder hens. Body weight of 30 ad-libitum-fed hens was approximately 700 g heavier than that of 30 restricted hens throughout most of the laying period. Mean egg output was lower in ad-libitum-fed hens (136.2 eggs) compared to restricted hens (176.6 eggs). A similar number of laying sequences (defined as consecutive days of laying) were observed in both groups of hens; however, the mean length of the prime sequence was 24.4 d for the restricted hens compared to 14.9 d for the ad-libitum-fed hens. Ad-libitum-fed hens had a higher incidence of intersequence pauses of greater than 11 d duration compared to restricted hens. Feed restriction did not improve fertility, embryo viability, or embryo production of eggs incubated for a period of 7 d. At 62 wk of age the carcasses of the restricted-fed hens contained on average 901 g of fat while the carcasses of the ad-libitum-fed hens contained 1270 g of fat. Ad libitum feeding reduced reproductive performance by reducing the length of the prime sequence and by increasing the number of long intersequence pauses. Key words: Broiler breeder hens, full-feeding, feed restriction, obesity, reproductive performance
A comparison of drip and non-drip nipple waterers used by weanling pigs
Authors: Ogunbameru B. O. , Kornegay E. T. , Wood C. M.
Published: March 2010

An evaluation of three waterer treatments: (1) pig-trainer nipple waterers adjusted to drip water for 3 d postweaning; (2) pig-trainer nipple waterers adjusted to not drip; and (3) conventional non-drip nipple waterers did not indicate significant (P > 0.05) differences in weekly and cumulative average daily feed intake, average daily gain and feed per gain ratios of weanling pigs, suggesting no advantage for the use of drip waterers. Key words: Pigs, nipple drinkers, growth, feed intake, feed conversion
The influence of adding estradiol to semen on reproductive performance of sows
Authors: Kirkwood R. N. , Thacker P. A.
Published: March 2010

One hundred gilts and one hundred mixed-parity sows of Yorkshire and Landrace breeding were inseminated with semen with or without an additional 10 μg estradiol-17β. Pregnancy rates of gilts receiving estradiol-supplemented and control semen were 90 and 79%, respectively (P < 0.09). The estradiol supplementation of semen did not improve the pregnancy rates or litter size in sows. Key words: Swine, artificial insemination, estradiol
Effects of creep feeding and breed composition on growth of heifer calves and milk production of their dams
Authors: Bailey D. R. C. , Gilbert R. P. , Beauchemin K. A. , Petitclerc D.
Published: March 2010

Heifer calves resulting from matings of Angus (A), Hereford (H), or Simmental (S) bulls with A and H cows were used to examine the effects of creep feeding (CREEP) and heifer genotype (CALFBRD; n = 14 AA, 18 HH, 10 AH. 10 HA, 19 SA, 15 SH) on their preweaning average daily gain (ADG) and the milk yield and milk composition of their dams during the 1987 and 1988 grazing seasons. Eight-hour milk yield was estimated by oxytocin-hand milking procedures at 62, 120, and 170 d from the beginning of the calving season. Dependent variables used in repeated measures analyses included heifer calf and cow ADG between consecutive sampling times, 8-h milk yield (MILK), milk composition (grams per 8 h and percent of fat, protein, and lactose in each sample (FATG, FAT%, PROTG, PROT%, LACTG, LACT%, respectively), fat-corrected milk (FCM) and solid-corrected milk (SCM) from each cow at each sampling time. Neither CREEP nor CALFBRD had any effect on any milk yield or milk composition variable except a slight effect of CALFBRD on LACT%. Year differences were found for cow ADG, FATG, FAT%, PROTG, PROT%, LACT%, FCM and SCM, but not for LACTG, MILK or calf ADG. Differences (P≤ 0.001) in calf ADG due to CREEP and CALFBRD were found. Age of cow was a significant source of variation for cow and calf ADG and all milk yield variables, but not for FAT%, PROT%, or LACT%. Time trends (within subject factors) were significant for all dependent variables. Time by Year effects were important for cow and calf ADG, MILK, SCM, PROTG, PROT%, and LACTG. Both the breed composition of calves and supplementation with creep feed influenced calf gains but had no effect on their dam's milk yield, milk composition, or changes in body weight. Key words: Beef cattle, creep feeding, milk yield, milk composition, average daily gain, repeated measurements
Effects of compensatory growth on protein metabolism and meat tenderness of beef steers
Authors: Bruce H. L. , Mowat D. N. , Ball R. O.
Published: March 2010

The relationships between meat tenderness and the changes in metabolism and body composition associated with compensatory growth in cattle were examined. Thirty-six steers were randomly allotted to 12 pens of three with three diets assigned randomly to the pens. Diets were alfalfa/grass silage, alfalfa/grass silage supplemented with corn gluten and bloodmeal and corn silage supplemented with soybean meal. Six steers from each treatment were slaughtered on each of days 124 and 175 of the trial to assess carcass characteristics. Following 124 d on trial, the remaining steers received a high-grain finishing diet. Blood and urine samples were collected throughout the trial for analyses of 3-methylhistidine, hydroxyproline and creatinine. At each slaughter, non-carcass components were cleaned and weighed. Lean, fat and bone proportions were estimated with a 9th-10th-11th rib dissection. Following dissection, the longissimus muscles were frozen at −10 °C for analysis of shear force, collagen and protein solubility. The steers fed the alfalfa/grass silage experienced compensatory growth within the first 14 d of the finishing phase. Steers fed the alfalfa/grass silage had lower gain throughout the growing phase (0–124 d), and empty body weight was less than that of the steers fed corn silage. Compensatory growth was observed in steers fed corn silage during the first 14 d of the finishing diet, as evidenced by higher gains compared with steers fed the other diets. Differences in body composition among treatments at 124 d and 175 d were related to dietary energy and not compensatory growth. Meat tenderness, measured by shear force, appeared to be affected primarily by dietary energy and intramuscular fat rather than by rate of growth. Key words: Compensatory growth, steers, meat tenderness, beef
Radioimmunoassay for insulin-like growth factor-I in bovine milk
Authors: Zhao X. , Groenewegen P. P. , McBride B. W. , Burton J. H. , Elsasser T. H.
Published: March 2010

This experiment was designed (1) to study the effectiveness of acid-ethanol extraction and gly-gly HCl incubation to dissociate the IGF-binding protein complex before IGF-I RIA measurements in bovine milk, and (2) to determine the influence of freezing/thawing and defatting of milk samples on IGF-I concentration of milk. Acidification of milk with acid-ethanol (acid-ETOH) liberated more IGF-I from its binding proteins than with gly-gly HCl. Milk samples obtained from three control cows and three rbST-treated cows (41–44 wk postpartum) were treated with acid-ethanol and assayed by a radioimmunoassay. IGF-I concentrations in the milk were 3.30 ± 1.40 for the control cows and 2.77 ± 1.36 ng mL−1 for the rbST-treated cows. Fat removal before or after freezing did not affect milk IGF-I measurements. The milk concentration of IGF-I after freezing/thawing twice was not different from that after freezing/thawing once. The radioimmunoassay resulting from this study should provide a tool for monitoring IGF-I concentrations in milk throughout the entire lactation. Key words: Milk, IGF-I, radioimmunoassay, cows
Profiles of serum IGF-I concentrations in calves from birth to eighteen months of age and in cows throughout the lactation Cycle
Authors: Kerr D. E. , Manns J. G. , Laarveld B. , Fehr M. I.
Published: March 2010

Blood samples were obtained from 16 female and 7 male holstein calves at birth and at 3-mo intervals until 15 to 18 mo of age. Monthly blood samples were also obtained from 34 holstein cows beginning 1 mo prepartum and continuing until the subsequent dry period. Serum concentrations of IGF-I were determined by RIA after serum-binding proteins had been removed by acid-gel chromatography. In calves there was an age-dependent increase in serum IGF-I concentrations, which reached a plateau after 9 mo of age. From 3 mo of age, these concentrations were greater in male animals. Analysis of data after retrospective grouping of female calves into fast, medium and slow growth rate groups indicated different (P < 0.05) IGF-I concentrations between groups; levels were greatest in the fastest-growing animals and lowest in the slow growth rate group. However, only weak relationships existed between serum IGF-I levels at 3 or 6 mo of age and body weight at 15 or 18 mo of age. In lactating animals, serum IGF-I concentrations were lowest at parturition. These levels slowly increased throughout lactation and returned to pre-partum levels within 15 d of drying off. Weak, negative relationships (P < 0.01) were found between serum IGF-I concentrations and milk production in 11 first lactation heifers (R = −0.34) and in 23 cows (R = −0.25). Serum IGF-I levels were not different between groups composed of the five best or five worst producing cows. The results of this study indicate that serum IGF-I concentrations are of little use in predicting lactational performance of dairy cows or growth performance of calves. Key words: Growth, sex, weight, milk production, cattle
Effect of long-term administration of human growth hormone-releasing factor and(or) thyrotropin-releasing factor on milk production, insulin-like growth factor-I and plasma constituents in dairy cows
Authors: Lacasse P. , Morisset J. , Petitclerc D. , Pelletier G. , Couture Y. , Gaudreau P. , Brazeau P.
Published: March 2010

Forty-seven Holstein cows (51 ± 7 d of lactation; 607 ± 78 kg BW) were randomly subjected to a 2 × 2 factorial arrangement based on milk production. Milk production and feed intake were recorded every day and milk and feed composition determined once a week for 33 wk (4 wk preinjection, 26 wk of injection and 3 wk postinjection). During the injection period, cows received daily s.c. injections (10:00 h) in the cervical area of saline (control), human growth hormone-releasing factor (1–29)NH2 (GRF; 10 μg kg−1 BW), thyrotropin-releasing factor (TRF; 1 μg kg−1 BW) or the combination of both releasing factors (10 and 1 μg kg−1 BW, respectively). Growth hormone-releasing factor enhanced milk production (P < 0.001; 22.1 vs. 24.2 kg 4% FCM per d), feed intake (P < 0.05; 19.0 vs. 19.8 kg DM per d), feed efficiency (P < 0.05; 1.14 vs. 1.21 kg 4% FCM per kg DM) and insulin-like growth factor-I concentrations (P < 0.05) but did not affect milk composition (P > 0.25) or average daily weight gain (P > 0.25). Thyrotropin-releasing factor did not affect nor did it interact with GRF on any of these variables except for average daily weight gain which was reduced by TRF (P < 0.05; 0.24 vs. 0.12 kg d−1) during the injection period. Milk production of GRF-treated cows returned to control levels after 3 wk following cessation of treatment. GRF treatment depressed (P < 0.05) serum urea, creatinine, triglycerides and glutamate pyruvate transaminase concentrations, while TRF treatment increased glucose levels (P < 0.05). In conclusion, daily s.c. injections of GRF for 6 months stimulated milk production by 9.5% and improved feed efficiency by 6.1% in dairy cows. Key words: GRF, TRF, milk production, plasma constituents, IGF-I
Effects of enzymes and nutrients in a bacterial inoculant on quality of timothy or alfalfa silage and dairy cow performance
Authors: Fredeen A. H. , McQueen R. E. , Browning D. A.
Published: March 2010

Timothy (trial 1) and alfalfa (trial 2) were inoculated at ensiling (33–37% dry matter (DM)) in concrete-stave, vertical silos with a culture of lactic acid bacteria (Lab; Lactobacillus plantarum and Pediococcus acidilactici) alone, or with additional nutrients and enzymes (Supersile®, Biotal Canada, Calgary, AB), and compared with an untreated (control) silage. Colony forming units of Lab, ammonia nitrogen (NH3-N), lactic acid and volatile fatty acid concentrations, pH, DM disappearance and temperature changes during ensiling were measured to assess silage quality. Nine dairy cows in mid-lactation (alfalfa) and nine cows in late lactation (timothy) were used to evaluate inoculants in repeated Latin square designs. Timothy silage that had been inoculated with Supersile or Lab had lower concentrations of acetic and butyric acid (P < 0.05) compared with the control. No other effects on silage quality were observed, and cow performance was not affected by using inoculants on either timothy or alfalfa in this study. Enzymes added in this experiment were not beneficial. Key words: Silage, inoculants, alfalfa, timothy, dairy, cow
Rate of starch degradation, apparent digestibility and rate and efficiency of steer gain as influenced by barley grain volume-weight and processing method
Authors: Mathison G. W. , Kerrigan B. K. , Vlach I. , Hironaka R. , Milligan L. P. , Weisenburger R. D.
Published: March 2010

The effects of barley grain volume-weight and processing method on rate of starch degradation, apparent digestibility, metabolizability and rate and efficiency of growth of steers were examined in a series of trials. The organic matter in an all-concentrate diet containing light barley grain (43 kg hL−1) was 2% less (P = 0.03) digestible than organic matter in diets containing heavier barley grains (59, 64 and 66 kg hL−1). No differences (P = 0.19) in methane production due to barley volume-weight were detected. Rates of gain (1.63–1.67 kg d−1, P = 0.90) and dry matter (DM) intakes (9.8–10.2 kg d−1, P = 0.52) of steers were not affected by including barley grains of differing volume-weights (43, 59 and 64 kg hL−1) in the diet of 90 growing-finishing steers. Steers fed the light barley had a 6% increase (P = 0.27) in DM:gain requirements in comparison with steers fed the two heavier barley grains. Steam-rolling barley in comparison with dry-rolling had no effect on either animal growth rate (1.66 versus 1.64 kg d−1, P = 0.84) or DM:gain ratio (6.15 versus 5.98, P = 0.40). Carcass characteristics were not influenced by grain type or grain processing method. Differences (P < 0.05) were detected in the rate of degradation of starch by amyloglucosidase among three barley grains. Starch in steam-rolled barley was degraded faster (P < 0.05) than starch in dry-rolled barley. Key words: Barley grain, steers, digestibility, gain, efficiency, starch degradation
Analysis of chromic oxide in small samples of feeds and feces using chlorine bleach
Authors: Suzuki E. Y. , Early R. J.
Published: March 2010

Chromic oxide concentration was determined spectrophotometrically (440 nm) on 10 to 100-mg samples of feeds and feces following a procedure involving oxidation with chlorine bleach. Average coefficients of variation and internal recoveries of added chromic oxide were < 2% and > 96%, respectively. The procedure is simpler and safer than other procedures based on strong oxidizing acids. Key words: Chromic oxide, feed, feces, analysis
Effect of dietary garlic (Allium sativum) on performance, carcass composition and blood chemistry changes in broiler chickens
Authors: Horton G. M. J. , Fennell M. J. , Prasad B. M.
Published: March 2010

Broiler chicks (7 d old) were fed 0, 100, 1000 and 10 000 mg kg−1 dried garlic in a starter diet for 35 d. Garlic increased average daily weight gain (P < 0.05) during the first 21 d on feed. There were no treatment effects on weight gain, feed intake or efficiency when the study was terminated after 35 d. Garlic did not influence muscle, adipose or bone growth (P > 0.05). Serum cholesterol and HDL were lower (P < 0.05) on the 10 000 mg kg−1 diet, though absolute differences were small and of questionable biological significance. Results of this investigation demonstrate that the inclusion of garlic in the diet did not improve the performance of broiler chickens, though plasma cholesterol and plasma HDL cholesterol concentrations were approximately 10% lower with the highest level of dietary garlic. Key words: Garlic, broiler chickens, performance
The effect of the halothane gene on pork production and meat quality of pigs reared under commercial conditions
Authors: Sather A. P. , Murray A. C. , Zawadski S. M. , Johnson P.
Published: March 2010

Production and meat quality traits were evaluated on 74 commercially raised heterozygous pigs (Nn) and 50 homozygous normal pigs (NN) at the halothane locus, with an average carcass weight of 79.7 kg. Eight-week weight, average daily gain and age to market, as well as measures of carcass quality (i.e., dressing percent, grade site fat and muscle depths and predicted lean yield) did not differ among pigs with Nn and NN genotypes. The longissimus dorsi muscle from Nn and NN pigs had similar subjective colour and structure scores. Reflectance meter readings (CIE L*-values) were significantly higher on chops from Nn than from NN pigs taken from the centre (57.4 vs. 55.6) and from the anterior portion (56.2 vs. 54.5) of the loin. Drip loss among Nn pigs was higher than among NN pigs for chops taken from the centre (4.8 vs. 3.8 g 100 g−1) and from the anterior portion (3.7 vs. 2.9 g 100 g−1) of the loin (P < 0.01). Soluble protein was 1.7% lower (P < 0.001) in Nn pigs compared with the NN pigs. Barrows attained market weight earlier (P < 0.05) than gilts, but they had a lower dressing percentage (P < 0.05) and greater grade fat depth (P < 0.001) and had 1.2% less predicted lean yield of carcass (P < 0.001) than gilts. Since meat quality declined without concomitant increases in growth rate or improvements in carcass quality, it was concluded that the intentional use of the halothane gene should be discouraged. Key words: Swine, production, carcass quality, meat quality, halothane gene