bluuebunny/crossref_metadata_2025 huggingface dataset:
Meat quality of heifers fattened to heavy weights to enhance marbling
Authors: Dubeski P. L. , Aalhus J. L. , Jones S. D. M. , Robertson W. M. , Dyck R. S.
Published: March 2010

Marbling is the primary factor affecting quality grades of youthful grain-fed cattle in the Canadian, American and Japanese grading systems. Cattle were fed for an extended period of time and to extreme slaughter weights to enhance marbling. The effects of slaughter weight, breed, nutrition, and grading site (12/13th rib-Canadian or 6/7th rib-Japanese) on meat quality were evaluated using 221 weaned heifer calves (exp. 1) and 216 yearling heifers (exp. 2) raised on high (HP) or moderate-high (MHP) planes of nutrition. Mean intramuscular fat concentration in longissimus muscle was 6.93, 8.94, and 9.86% at mean slaughter weights of 500, 590, and 680 kg, respectively (exp 1) and 6.84% and 9.02% at 590 and 680 kg (exp. 2). HP carcasses had more intramuscular fat and lower shear values and drip losses than MHP carcasses (P ≤ 0.05). Angus carcasses had more intramuscular fat and lower shear values than the other breeds studied. Holsteins on the HP diet produced tender meat with a high amount of intramuscular fat whereas Holsteins on the MHP diet produced tougher meat with less intramuscular fat (P < 0.05). The 6/7th rib site had lower marbling scores, lighter meat, higher drip losses and lower shear values (P ≤ 0.001) than the 12/13th rib site. Intramuscular fat accounted for only 3 to 7% of the variation in shear force. Breed, nutrition, and slaughter weight had little effect on most measurements of meat quality except intramuscular fat and shear force. Key words: Beef cattle, meat quality, intramuscular fat, tenderness
Whole canola/pea and whole canola/canola meal blends in diets for broiler chickens 2. Determination of optimal inclusion levels
Authors: Fasina Y. O. , Campbell G. L.
Published: March 2010

Whole canola/pea (WCP, 1:1 wt/wt) or whole canola/canola meal (WCC, 3:1 wt/wt) were heat-processed using a commercial pellet mill prior to incorporation in broiler starter (0–20 d) and finisher diets (20–40 d). The pelleted blends readily disintegrated in the preparation of the mash diets. Body weight gain of broilers (0–40 d) fed WCP (0, 10, 20, or 30%) or WCC (0, 5, 10, or 15%) declined linearly with level of dietary inclusion (P < 0.01). Feed intake declined curvilinearly (P < 0.01) with both blends, with lower intake most apparent at the higher inclusion levels. Feed/gain increased for broilers fed WCP or WCC (P < 0.01). Overall broiler mortality declined incrementally with inclusion of WCP (P < 0.07) or WCC (P < 0.03) in the diet. Although there was no distinct limitation on the dietary inclusion levels of either blend, the low feed intake with broilers fed 15% WCC indicated that its level should not exceed 10% of the diet. Key words: Canola seed, canola meal, peas, broiler chickens
Management, gain and productivity of Peace Country bison (Bison bison)
Authors: Rutley B. D. , Jahn C. M. , Hudson R. J.
Published: March 2010

Three thousand three hundred twenty-nine (3329) bison from 16 Peace Country bison herds were weighed between November 1992 and October 1994 to determine body weight, gain and to measure herd productivity. A survey of management practices was used to develop three producer profiles: 1) small herds (∼30 head), 130 ha and significant off-farm responsibilities, 2) full-time – 110 breeding females on 1040 ha, and 3) large ranches – 450 breeding females on 2080 ha. Calf winter weight was significantly (P < 0.0001) affected by HERD, YEAR and GENDER with males (196 ± 2.0 kg) significantly heavier (P < 0.0001) than females (180 ± 2.6 kg). Calves of both genders were heavier in 1993 than in 1992. Producers reporting herd health problems also had calves with lower (P < 0.0001) winter weights than herds reporting no health problems (175 ± 1.2 kg vs. 198 ± 1.2 kg). Seasonal ADG ranged from −0.08 kg d−1 to 0.56 kg d−1. A significant relationship existed between winter ADG and subsequent summer ADG (Y = −0.50X + 0.71; P < 0.0001). The results from this study of Peace Country bison are sufficient to serve as industry benchmarks to which producers can compare their herds. Key words: Bison, management, weight, gain, productivity
Effects of tempering and degree of processing of barley grain on the performance of bulls in the feedlot
Authors: Mathison G. W. , Engstrom D. F. , Soofi-Siawash R. , Gibb D.
Published: March 2010

A 2 × 3 factorially designed experiment with 216 bull calves (288 ± 43 kg) was conducted in which tempered and dry barley grains were lightly rolled (most of kernels cracked, few broken), medium rolled, or crushed (almost all kernels broken) and included in a feedlot diet containing 90% concentrate and 10% barley silage on a dry matter (DM) basis. In the tempering process 6% water was added to the control barley, which initially contained 13% moisture, and the damp grain was allowed to stand overnight at room temperature before rolling. Tempering had no influence on rate or efficiency of gain of the bulls during the 134-d trial or on carcass characteristics. Cattle fed slightly rolled, medium rolled, and crushed barley (kernel thicknesses of 2.70, 2.56 and 2.31 mm) gained 1.55, 1.57 and 1.61 kg d−1, respectively, with no difference detected between treatments. Corresponding DM intakes were 8.04, 7.79 and 7.54 kg d−1 (P < 0.05). Dry matter intake to gain ratios were 5.20, 4.96 and 4.68 (P < 0.05). Carcasses of bulls fed crushed barley had more (P < 0.05) grade fat than bulls fed slightly rolled barley. It was concluded that there was no advantage in tempering barley which initially contained 13% moisture. Efficiency of gain was improved as the degree of processing of barley was increased. Key words: Bulls, barley, tempering, processing, gain, feed efficiency
Effect of oral administration of folate sources on plasma folate levels in pigs: Comparison between reduced and oxidized forms of folate
Authors: Mizuno Y. , Kokue E. , Ohnishi N. , Toride Y.
Published: March 2010

Two experiments were conducted to evaluate the response of plasma folate levels after oral administration of oxidized or reduced forms of folates, using seven Göttingen minipigs. Plasma folate levels, tetrahydrofolate (THF) and 5-methyltetrahydrofolate (5CH3-THF), were determined by high-performance liquid chromatography with electrochemical detection. In exp. 1, the absorption of the oxidized form of folate [(synthetic folic acid(FA)] and the reduced forms of folate (5-formyltetrahydrofolate (5HCO-THF), liver powder and digested bacterial cell powder (DBCP) were evaluated by measuring changes in plasma folate levels after a single oral administration. Liver powder and DBCP contained much reduced forms of folate. The administration of the reduced form of folates increased plasma THF levels while the levels of plasma THF and 5CH3-THF decreased after FA administration. In exp. 2, plasma folate levels were measured after long-term oral administration of FA for 30 d. Immediately after the beginning of the administration, the levels of both THF and 5CH3-THF decreased significantly and remained at a low level during the 30-d administration. Supplementation of sow feed with FA has been recommended in many countries improving reproductive performance. The present study, however, suggests that the oral administration of an oxidized form of folate, FA, may not be as effective as previously thought, and the reduced forms of folate might be preferable for the supplementation of pig feeds. Key words: Folate (reduced), folic acid, pig, oral administration, bacterial cell wall, absorption
Influence of feeding operation and social factors on cattle locomotion in free stall barns
Authors: Uetake K. , Yayou K. , Okamoto T.
Published: March 2010

The influence of feeding operation and social factors on voluntary movement of cattle was studied with a group of nine Holstein calves in free stall barns. The results of this study suggest that cattle can move more voluntarily when rations are put beyond the place that farmers want them to walk through. The results also suggest that conflicts between motivations for approaching rations and avoiding competitive feeding behaviour should be considered when efficient systems of locomotion control of cattle groups are designed, such as in AMSs. Key words: Dairy cattle, feeding, social behaviour, motivation
Lipid peroxidation as one mode of action in ochratoxin A toxicity in rats and chicks
Authors: Hoehler Dirk , Marquardt Ronald R. , Rohlich Andrew A.F.
Published: March 2010

The objective of this study was to determine whether lipid peroxidation is one mode of action in ochratoxin A (OA) toxicity in vivo. Lipid peroxidation was monitored by analyzing malondialdehyde (MDA) in different tissues by HPLC. A refinement study on the MDA assay was carried out, which showed the importance of the addition of an iron catalyst for the decomposition of hydroperoxides to yield a maximum amount of MDA from a given sample. The rat experiment was designed in a 2 × 2 factorial arrangement using 4 × 6 animals. The four different diets were fed for 21 d and contained either 1% corn oil and 9% tallow (Diets I and III) or 10% corn oil (Diets II and IV); in groups III and IV, 5 mg OA were added per kilogram of diet. For the chick experiment 4 × 8 Leghorn cockerels received diets for 14 d with no added sunflower oil (Diets I and III), whereas the diets of groups II and IV were supplemented with 2.5% sunflower oil. In groups III and IV, 2.5 mg OA were added per kilogram of diet. In both experiments OA decreased the performance of the animals significantly. In the rat experiment an increased lipid peroxidation due to a higher dietary level of unsaturated fatty acids could be obtained, when muscle samples were oxidatively stressed with Fe3+ and ascorbic acid. In the chick experiment there were very clear effects of the dietary treatment on the MDA concentrations of different tissues, as both a higher supply with unsaturated fatty acids and OA increased most of the MDA values significantly. These data suggest that lipid peroxides are formed in vivo by OA, but the effects may vary considerably from species to species, and may also be influenced by other factors. Key words: Ochratoxin A, lipid peroxidation, malondialdehyde, rat, chick
The effects of porcine somatotropin, gender and porcine stress syndrome on growth, carcass composition and pork quality
Authors: Dugan M. E. R. , Tong A. K. W. , Carlson J. P. , Schricker B. R. , Aalhus J. L. , Schaefer A. L. , Sather A. P. , Murray A. C. , Jones S. D. M.
Published: March 2010

Lacombe breed pigs (72 gilts, 72 barrows) of three genotypes with respect to the porcine stress syndrome (normal, heterozygous, or homozygous for the halothane gene), were treated from 57 to 106 kg body weight with daily injections of 0.9% saline containing 0 or 3 mg of recombinant porcine somatotropin (pST) in a randomized block design. Pigs receiving pST had lower average daily feed intakes (ADF), greater average daily gains (ADG) and lower feed conversion efficiencies (FCE). Gilts relative to barrows had lower ADG, ADF and higher FCE. Gilts versus barrows and pigs treated with pST had reduced fat depths and greater loin depths at the 10th rib. Pigs homozygous for the halothane gene had reduced loin lean structure and color scores, greater light reflectance (L*), and lower soluble protein contents as expected, and these genotypic effects did not interact with pST treatment. Sex by pST treatment interactions (P < 0.05) were found for loin depth, moisture content, color score and L* values indicating barrows respond more favorably to pST treatment than gilts. Generally, pST treatment, gilts relative to barrows, and possession of the halothane gene increased carcass lean and reduced subcutaneous fat levels. Sex by pST treatment interactions were found for picnic lean (lower shoulder; P < 0.05), ham lean (P < 0.05), and total carcass lean (P = 0.09) further supporting the theory that barrows benefit more than gilts to pST treatment. No significant interactions were found between genotype and pST treatment for any qualitative muscle traits. Thus, pST treatment had no direct effect on meat quality and was not found to interact with the halothane gene. However, pST interactions with sex indicated barrows respond quantitatively and qualitatively more favorably than gilts to pST treatment. Key words: Somatotropin, porcine somatotropin, pork, porcine stress syndrome, stress, pigs, growth
Effect of dietary lard on performance, fatty acid composition and susceptibility to lipid peroxidation in growing-finishing female and entire male pigs
Authors: Lopez-Bote C. J. , Sanz M. , Isabel B. , Ayala P. Perez de , Flores A.
Published: March 2010

The effect of increasing the energy concentration of growing-finishing pig diets through inclusion of lard on performance, carcass and meat composition and lipid susceptibility to peroxidation was studied. A total of 720 Landrace × Large White male and female pigs (equal number of entire males and females) were used. Experimental diets were formulated to have a low (3000 kcal ME kg−1) or high (3200 kcal ME kg−1) energy level, but in all cases to have a constant lysine:ME ratio. This was achieved using a low (6.8 g kg−1) and a high (49.3 g kg−1) level of dietary lard inclusion. Gilts had lower daily gain (P < 0.0001) and worse feed conversion efficiency (P < 0.0001) than entire males. Susceptibility to oxidation was not affected by sex. Fat concentration in pig diets equilibrated in metabolizable energy and protein did not modify average gain, but reduced feed intake (P < 0.02), improved the gain:feed ratio (P < 0.0001), increased dressing percentage (P < 0.02) and produced higher carcass weight (P < 0.01). Carcass backfat and lean percentage were not affected by dietary treatment. A reduction in the proportion of (n-3) fatty acids in phospholipids (P < 0.03), a higher (n-6):(n-3) ratio (P < 0.01) and a lower susceptibility of muscle homogenates to oxidation was found in animals receiving higher levels of dietary lard (P < 0.01). Key words: Pig, boar, diet, lard, lipid oxidation
Lifetime profitability measures for dairy cows and their relationships to lifetime performance traits
Authors: Kulak K. K. , Dekkers J. C. M. , McAllister A. J. , Lee A. J.
Published: March 2010

The objectives of this study were to evaluate and compare alternative measures of individual cow lifetime profitability and to determine what lifetime traits are significantly related to profitability of dairy cattle. Profitability measures considered were: 1) lifetime milk revenue minus lifetime feed costs (MMF); 2) lifetime profit (LP); 3) discounted lifetime profit (DLP); 4) annualized DLP per year of total life (ADLPLTL); 5) annualized DLP per year of productive life (ADLPLPL); 6) DLP adjusted for opportunity cost of postponed replacement (DLPOC), and 7) economic efficiency (EF). Data for this study consisted of 1112 lifetime performance records of Holstein cows from the National Cooperative Dairy Cattle Breeding Project, which was implemented by Agriculture Canada in 1972. Correlations were highest among MMF, LP, and DLP. EF had slightly lower correlations with MMF, LP, and DLP, but higher with ADLPLTL and ADLPLPL. ADLPLPL and DLPOC had low correlations with all other measures. DLPOC was recommended as the best because it considered the opportunity costs of postponed replacement.For DLPOC, average milk revenue per lactation was found to be the most important income trait, followed by length of productive life. Days dry (average over completed lactations) had the greatest negative impact on profitability. Age at first calving and average number of veterinary treatments for reproductive diseases over lactations were both negative contributions to profit. Lifetime traits accounted for 65% of variation in DLPOC. Key words: Dairy cow, profitability, lifetime traits
Potential use of video imaging and real-time ultrasound on incoming feeder steers to improve carcass uniformity
Authors: Basarab J. A. , Milligan D. , McKinnon J. J. , Thorlakson B. E.
Published: March 2010

A study was conducted to evaluate two feeder cattle sorting systems for their ability to improve carcass backfat uniformity. One thousand and thirty-one yearling steers (407 kg; SD = 46.2 kg) were assembled and processed at three Alberta feedlots. Each steer was weighed and ultrasonically assessed for backfat thickness and l. dorsi area 88 to 154 d before slaughter. Rump height, frame score and muscle score were also recorded using an automated video imaging system, called the Musculo-Skeletal Imaging (MSI) Scanner. Sorting System 1 (MSI sorting system) used initial body weight, frame score and muscle score to hypothetically cluster animals into five "predicted days on feed" (PDOF) groups. Sorting System 2 (Oltjen sorting system) used initial body weight, rump height, backfat thickness, feeding inputs and a computer model of cattle growth to hypothetically cluster animals into five PDOF groups. Each sorting system was compared with the traditional system of visually sorting cattle at the end of the feeding period for its ability to reduce the variability in carcass backfat thickness. Steers were identified for slaughter when they reached the body weight and condition desired by the feedlot manager. The MSI sorting system decreased the variability in slaughter weight by 14.3% (P < 0.001), but had no effect on the variability in carcass backfat thickness compared with the observed variability. The change in predicted net return resulting from the MSI sorting system varied between feedlot from $−4.09 to $8.82 head−1 slaughtered. The Oltjen sorting system increased the variability in slaughter weight by 33.9% (P < 0.001) and decreased the variability in carcass backfat thickness by 15.5% (P < 0.001). The predicted net return from the Oltjen sorting system varied between feedlot from $−3.65 to $11.55 head−1 slaughtered. Further work is required to determine the actual effect of sorting systems on feed efficiency, carcass quality and net return. Key words: Sorting, computer model, electronic identification, steers
Comparison of rebreeding policies for Ontario dairy herds
Authors: Plaizier J. C. B. , King G. J. , Dekkers J. C. M. , Lissemore K.
Published: March 2010

Net-revenues of rebreeding policies that differed in the maximum allowable days after calving for breeding were compared using data generated by a dynamic stochastic simulation model of Ontario dairy herds. Such comparisons benefit farmer decision support, as rebreeding decisions are important management choices. Rebreeding up to 168 d after calving only was least optimal. Hence, the rebreeding period should not be too short. At average and high herd fertility, a rebreeding policy under which cows with a mature equivalent milk production level lower than 80%, between 80 and 100%, and greater than 100% of the herd average were not rebred, bred up to 168 d after calving, and bred up to 250 d after calving, respectively, resulted in higher net-revenue than rebreeding policies that used a single cut-off for all cows. Differences in net-revenue between the optimal and the least optimal policy were $217.90 and $114.40 per cow per year for the lowest and highest simulated reproductive performance, respectively. At low herd fertility, rebreeding up to 364 d postpartum was optimal. However, at this level of performance emphasis should be given to improving fertility, rather than choice of rebreeding policy. Key words: Dairy cattle, simulation, economics, insemination policy, rebreeding policy
An evaluation of a new method for collection of exocrine pancreatic secretion in the pig
Authors: Winnicki Tadeusz , Brzeski Wojciech
Published: March 2010

Surgical techniques for the cannulation of the pancreatic duct via the minor duodenal papilla in the pig are described. The dynamics of pancreatic juice secretion and animal behavior for pigs operated on according to a new method are compared with conventional animals. A means of redirecting the exocrine pancreatic secretion into the duodenum was also demonstrated. Key words: Cannulation, pancreas, pig
Effects of diet and slaughter endpoint on carcass composition and beef quality in Charolais cross steers
Authors: Mandell I. B. , Gullett E. A. , Buchanan-Smith J. G. , Campbell C. P.
Published: March 2010

One hundred and eight Charolais cross steers were used to compare forage versus grain feeding as affected by slaughter endpoint on carcass composition and palatability attributes of beef. Diets included a 97% alfalfa silage ration or 68% high moisture corn, 25% alfalfa silage ration from start of test to finish or a ration of 97% alfalfa silage from start of test to day 42 of the trial followed by the 68% high moisture corn ration until slaughter. Cattle were slaughtered at either 4, 7, or 10 mm ultrasound backfat. Grain feeding increased (P = 0.01) average daily gain and decreased (P = 0.01) days to finish, while carcass weight and grade fat were similar (P > 0.10) between diets. Palatability attributes were generally unaffected by diet with the exception of slightly less (P = 0.09) beef flavour and more (P = 0.01) off flavour in forage-fed beef versus grain-fed beef. Higher (P = 0.01) concentrations of linolenic acid and lower (P = 0.09) concentrations of oleic acid in forage-fed beef may be partially responsible for diet differences in flavour. As slaughter endpoint increased from 4 to 7 mm backfat, average daily gain, days to finish, and carcass weight increased (P = 0.01). Palatability attributes assessing juiciness and flavour did not differ (P > 0.10) between slaughter endpoints. Beef from cattle slaughtered at 10 mm backfat was rated higher (P < 0.05) for softness, tenderness, and chewiness than beef from cattle slaughtered at 4 and 7 mm finish. Slaughter endpoint effects on "tenderness" attributes may partially explain why less tender beef is entering the marketplace. Key words: Beef cattle, alfalfa, grain, palatability, shear, fatty acids
Effects of trilostane, an inhibitor of 3β-hydroxysteroid dehydrogenase, on the onset and duration of parturition in sows and gilts
Authors: Chandolia R. K. , Kirkwood R. N. , Thacker P. A.
Published: March 2010

On day 113 of gestation, 31 of 62 sows received an oral dose (750 mg sow−1) of trilostane, an inhibitor of 3β-hydroxysteroid dehydrogenase. All sows received an injection of PGF2α 3 h later. The onset of farrowing in trilostane-treated sows was earlier than controls (25.7 vs. 28.8 h; P < 0.05) and more sows farrowed during the normal working day (83.9 vs. 64.5%). This effect was due to a decrease in progesterone concentration with no adverse effect on piglets or sows. Key words: Farrowing, trilostane, sow
Pre- and post-mating dietary supplements of folic acid and uterine secretory activity in gilts
Authors: Duquette J. , Matte J. J. , FarMer C. , Girard C. L. , Laforest J. -P.
Published: March 2010

The present study was carried out to determine the effects of pre- and (or) post-mating dietary supplements of folic acid on uterine secretions and secretory activity on day 12 of gestation. Crossbred gilts were assigned randomly to three treatments: SS) a dietary supplement of 15 mg of folic acid kg−1 of diet from the estrus before mating (approximately day –21) until day 12 of gestation (n = 9), 0S) the same folic acid supplement from mating (day 0) to day 12 of gestation (n = 10), and 00) no supplement of folic acid (n = 10). At slaughter (day 12 of gestation), one uterine horn was flushed with 20 mL of PBS to collect embryos and uterine flushings, while samples of uterine tissue were collected from the other horn. Supplementary folic acid (0S and SS) increased total folates in uterine flushings (P ≤ 0.05) as well as concentrations of folates in the endometrium (P ≤ 0.0004) and in the whole uterine tissue (endometrium + myometrium: P ≤ 0.0001). Total amounts of prostaglandin (PG)E2 and PGF2α in uterine flushings were not affected (P ≥ 0.8) by any treatment but estradiol-17β was numerically 40% lower (P ≥ 0.12) in uterine flushings of 0S and SS sows. Samples of endometrium (15–17 mg) were cultured for 2 to 7 h. Concentrations of PGE2 and PGF2α in the culture medium increased with the duration of incubation (P ≤ 0.0001) but there was no treatment effect (P ≥ 0.4). The inconsistency between the folic acid response seen in the present study and in previous results using multiparous sows suggests that the impact of this vitamin on sow reproduction might be linked to the parity (and/or prolificacy) of the animal. Key words: Folic acid, uterine tissue, secretion, prostaglandins, gilts
Effect of feeding barley based diets on animal performance, carcass characteristics and meat quality of crossbred beef cattle with and without Wagyu genetics
Authors: Mir P. S. , Bailey D. R. C. , Mir Z. , Jones S. D. M. , Entz T. , Husar S. D. , Shannon N. H. , Robertson W. M.
Published: March 2010

Growth performance, carcass characteristics and meat quality of European and British crossbred (EBC; no Wagyu genetics; 28 heifers and 30 steers) cattle were compared with crossbred cattle with 75% Wagyu genetics (WC; seven heifers and 14 steers) to determine the influence of Wagyu genetics on marbling grade of beef cattle fed barley-based diets in a factorial design experiment. Weaned calves (250 d average age) were fed, one of two diets (diet 1, 35% barley grain; diet 2, 40% hay cubes on DM basis, with barley silage, protein and vitamin/mineral premix) for 84 d and then fed diet 1 until they weighed 394 to 432 kg. All cattle were finished on an 80% (DM basis) rolled barley diet and slaughtered. Carcasses were graded and samples procured for meat quality and Warner–Bratzler shear force determination. Number of days on backgrounding diets to arrive at target weight (380 kg) was greater (P < 0.05) for the WC cattle, owing to relatively lower ADG, but days on the finishing diet were fewer for these cattle, compared with EBC cattle. Warm carcass yield (dressing percent) was greater (P < 0.05), but backfat depth was lower (P < 0.05) for WC cattle relative to that of EBC cattle, yet proportion of lean meat yield was similar. Eighty three percent of WC cattle carcasses had Canada AAA (small or more) marbling grade compared with 13% for EBC cattle carcasses. Mean shear force of meat samples from EBC and WC cattle was 4.2 and 3.8 kg, respectively. Results indicated that the extent of carcass marbling can be increased by incorporating Wagyu genetics but age at slaughter of WC cattle was 19 d greater than that of EBC cattle and carcass size was reduced. Key words: Average daily gain, carcass characteristics, European and British crossbred, feed to gain ratio, meat quality, Wagyu crossbred cattle
The influence of dietary cereal grain source and feed enzymes on the cooking properties and palatability attributes of beef
Authors: Jeremiah L. E. , Beauchemin K. A. , Jones S. D. M. , Gibson L. L. , Rode L. M.
Published: March 2010

A total of 54 crossbred steers of similar genotype were randomly allocated to a 2 × 3 factorial arrangement of treatments including 2 diets (corn vs. barley) and 3 enzyme treatments (control, enzyme 1, and enzyme 2). Diets consisted of 95% concentrate and 5% silage for 105 to 147 d, following a 14-d step-up period from a 30% concentrate, 70% silage diet (dry matter basis). All animals were slaughtered using simulated commercial conditions after attaining a mean weight of 567.5 kg. The longissimus thoracis (LT) muscles were excised between the 9th and 12th ribs at 24 h postmortem. They were then vacuum packaged and aged for 14 d at 2 °C, before being frozen at −30 °C for subsequent evaluation by an experienced semi-trained laboratory panel and a highly trained flavor/texture profile panel. Source of dietary grain and dietary enzyme treatment generally failed to produce any important effects on the cooking properties or palatability attributes of beef. Beef from animals fed barley-based diets was slightly inferior to beef from animals fed corn in certain flavor attributes. Addition of dietary enzymes to the feed, irrespective of the source of dietary grain, appeared to produce a slightly beneficial effect on beef flavor. The magnitude of these effects, however, makes them of little or no practical importance. Key words: Beef, palatability, cooking properties, corn, barley, dietary enzymes
Traceback success rate of an electronic feedlot to slaughter information system for beef cattle
Authors: Basarab J. A. , Milligan D. , Thorlakson B. E.
Published: March 2010

The traceback success rate of an electronic feedlot to slaughter information system was evaluated using 4186 yearling cattle from three Alberta feedlots. Each animal was identified with an external Allflex electronic identification (EID) eartag before the end of the feeding period. The EID number was scanned with stationary Allflex TIRIS readers at the abattoir and electronically linked to its carcass data. The traceback success rate was 39.8% from abattoir to feedlot and 46.4% from abattoir to herd of origin. Key words: Allflex, electronic identification, reliability, transponder, cattle
A comparison of changes in whole body and skin amino acid metabolism of sheep in response to 24 h continuous infusions of variants of insulin-like growth factor 1
Authors: Lobley G. E. , Lee J. , Edwards J. Hocking , Harris P. M.
Published: March 2010

Because of the economic significance of wool to many sheep production systems, attempts to partition amino acids towards skin and wool protein synthesis have included both nutritional and hormonal methods of manipulation. A variant of insulin-like growth factor 1 (IGF-1) has previously been shown to transiently increase protein synthesis in the skin of sheep and the current study extended that work by comparing the effects of a 24 h, close-arterial, skin infusion of IGF-1, in the form of either recombinant human (rhIGF-1) or an extended variant (LR3IGF-1), on both whole body and skin amino acid metabolism adult, castrated Romney sheep, with three animals allocated to each treatment. There were no differences in food intake between the two treatment groups. The plasma concentration of immunoreactive IGF-1 of sheep infused with rhIGF-1 increased (P < 0.01) with time of administration, but decreased (P < 0.05) after 24 h of LR3IGF-1 infusion. Administration of both IGF-1 variants caused a substantial and sustained decrease in arterial insulin to less than 50% (P < 0.05) of pre-infusion values, while arterial plasma glucose concentrations were only reduced by 7%. Alterations in whole body and skin protein metabolism were assessed from continuous infusions of mixed [U-13C] AA, [2,6 ring 3H]phenylalanine and [35S]cysteine. Within 4 h both AA concentrations and whole body plasma ILR of essential and non-essential AA were decreased (P < 0.05 for seven AA) by IGF-1 infusions. Both IGF1 variants caused acute increases (P < 0.05) in skin blood flow and, for 13 of the 15 AA measured, isotopic transfers (range 50–220%; P < 0.05 for cysteine and tyrosine), which probably reflect increased protein synthesis. By 24 h skin blood flow, AA uptake and protein synthesis had returned to pre-infusion values. Strategies based on exogenous application, or enhanced endogenous production, of IGF-1 are unlikely, therefore, to produce persistent anabolic responses. Key words: Insulin-like growth factor 1, skin, sheep, protein synthesis
The effect of feed deprivation on gastrointestinal respiration and Na+, K+-ATPase in chicks
Authors: Park H. , McBride B. W. , Milligan L. P. , Trouten-Radford L. M.
Published: March 2010

In order to investigate the effect of nutrient availability on energy metabolism of the gastrointestinal tract (GIT) of chicks, two experiments were conducted. In exp. 1, jejunal slices from male White Leghorn chicks at 14 d were incubated in salt-based balanced medium (SBM) or complex medium (CM) for 30 min. The total O2 (TO2) and ouabain-sensitive O2 (OSO2) consumption in jejunal slices were significantly decreased in SBM. The results from exp. 1 imply that when the GIT mucosa is subjected to nutrient deprivation, the utilization of oxygen consumption is altered primarily by shifting active Na+ pump activity. Changes in the TO2, OSO2 and amiloride-sensitive O2 (ASO2) uptake in response to feed deprivation in the small intestine of male White Leghorn chicks were investigated in exp. 2. There was little change in TO2, OSO2 and ASO2 per unit of dry matter of the small intestine from birds subjected to fasting, except for a TO2 decrease in the jejunum of 48 h fasted chicks. However, there were significant reductions in TO2, OSO2 and ASO2 in the jejunum when data were expressed per unit DNA. Na+, K+-ATPase-dependent respiration represented 31–37% of TO2 in the avian jejunoileum. Amiloride-sensitive respiration accounted for 10–18% of TO2 in the jejunoileum. The maximal amount of 3Houabain binding sites of jejunal enterocytes was significantly decreased in chicks fasted for 48 h (P < 0.05). Key words: Oxygen consumption, fasting, Na+, K+-ATPase, ouabain, jejunum, ileum, chicks
Nitrogen balance and myofibrillar protein turnover in double muscled Belgian Blue bulls in relation to compensatory growth after different periods of restricted feeding
Authors: Eenaeme C. Van , Evrard M. , Hornick J. L. , Baldwin P. , Diez M. , Istasse L.
Published: March 2010

Nitrogen balance and myofibrillar protein breakdown were studied in 16 double-muscled Belgian Blue bulls during a low growth period (0.5 kg d−1) (LGP) of 4 mo (L4), 8 mo (L8), or 14 mo (L14) and the subsequent fattening period (rapid growth period, RGP). The control group (CG) was given a conventional fattening diet; the others received a low-energy, low-protein diet during LGP, and the same diet as the CG during RGP. Measurements were made halfway through the LGP, l mo after the beginning of the fattening period, and 1 mo before slaughter. Nitrogen balance was about half of CG (P < 0.001) during LGP, e.g., 50.8, 21.3, 25.8, and 23.8 g d−1, for CG, L4, L8, and L14, respectively. Between LGP and RGP, N balance increased by about 18 g N d−1 above the control in the compensating groups L4, L8 and L14. This was due to the higher digestibility and the higher metabolizability of the nitrogen in the fattening diet. Lower muscle protein accretion during the LGP resulted from decreased synthesis (P < 0.001) and degradation (P < 0.05) compared with the GC. When changing to RGP different evolution patterns were observed in the three formerly restricted groups, e.g. after a short restriction (L4) both synthesis and degradation rose during the RGP but declined towards the end. After a longer restriction (L8 and L14), synthesis and degradation increased and remained high. The magnitude of these increases was inversely proportional to the length of the restriction period. Key words: Belgian Blue bulls, compensatory growth, nitrogen balance, muscle, muscle protein breakdown
Effect of the halothane genotype and stress on animal performance, carcass composition and meat quality of crossbred pigs
Authors: Pommier Serge A. , Pomar Candido , Godbout Daniel
Published: March 2010

One hundred and twenty-eight pigs, progeny of Yorkshire–Landrace sows (NN genotype) sired by Duroc boars (Nn genotype) representing 64 gilts (32 and 32 NN) and 64 barrows (32 Nn and 32 NN) were slaughtered at 104 kg liveweight under two management schemes: stress (S) and not stressed (NS), at 105 kg average liveweight. Feed-to-gain ratio was significantly lower (1.9%) for Nn pigs compared to NN pigs (P < 0.05). The pH-45 of S and Nn pigs were lower than NS and NN pigs, respectively (P < 0.01). Carcass yields were greater for Nn pigs (0.5%) compared with NN pigs (P < 0.05) and S pigs displayed greater carcass yields than NS pigs (P < 0.001). Ultimate pH of the loin was lower for NS pigs compared with S pigs (P < 0.05). Longissimus dorsi CIE L values were greater for Nn pigs than for NN pigs (P < 0.05) and percent water exudate from muscle of Nn pigs was greater (38%) than for muscle of NN pigs (P < 0.001). Carcasses from Nn pigs had 2.3% more lean than carcasses from NN pigs (P < 0.05). Results of this study support previously published reports on the effects of the halothane gene and demonstrate that the advantages observed on carcass composition must be weighed against the negative effects on meat quality. Key words: Swine, carcass composition, meat quality, halothane gene, stress.
Acute effects of epidermal growth factor on Na+, K+-ATPase-dependent oxygen consumption and the amount of the enzyme units in enterocytes isolated from the jejunum of chickens
Authors: Park H. , McBride B. W. , Milligan L. P. , Trouten-Radford L. M.
Published: March 2010

Enterocytes from jejunum of male White Leghorn chickens aged 14 d and 20 wk were used to investigate the short-term effect of epidermal growth factor (EGF) on total O2 uptake (TO2) and Na+, K+-dependent O2 uptake (OSO2) and intracellular pH (pHi). Total O2 uptake and OSO2 was decreased (P < 0.05) in enterocytes, isolated from both young and adult birds as concentration of EGF increased in the incubation medium from 0 to 100 ng mL−1. The energy required to support Na+, K+-ATPase activity in jejunal enterocytes obtained from 2-wk-old and 20-wk-old birds was 33–37% and 31–34% of total O2 uptake, respectively. No changes were observed in the amount of the maximal binding sites for 3H-ouabain in enterocytes incubated with EGF; the regulation had not caused rapid decrease in the amount of Na+, K+-ATPase units in the basolateral membrane of enterocytes. Epidermal growth factor caused short-term reduction of pHi as did amiloride. Seemingly, an acute action of EGF in chicken enterocytes in vitro is to reduce the activity of a fixed number of Na+, K+-ATPase units in enterocytes by decreasing Na+, H+-antiport-dependent Na+ influx. Key words: Oxygen consumption, enterocytes, Na+, K+-ATPase, ouabain, epidermal growth factor, intracellular pH, chicks
Eating quality of beef from animals fed wet brewers' grains and wheat-based wet distillers' grains
Authors: Shand P. J. , McKinnon J. J. , Christensen D. A.
Published: March 2010

The eating quality of beef from steers fed either conventional, brewers' grain or wheat-based distillers' grain rations during backgrounding and finishing was assessed. Carcass traits, raw proximate composition and fatty acid composition of the longissimus muscle were generally unaffected (P < 0.05) by dietary treatment. Furthermore, diet had no effect on sensory properties (tenderness, juiciness, flavor) and shear values of loin roasts. Thus, beef producers can take advantage of these alternative protein sources to provide lean, nutritious beef for consumers. Key words: Feed, diet, beef, wet brewers' grains, wet distillers' grains, sensory evaluation
Effect of exogenous progesterone following mating on embryo survival in the gilt
Authors: Yu Z. , Kirkwood R. N. , Thacker P. A.
Published: March 2010

At first observed estrus (day 0), 85 Yorkshire × Landrace gilts were artificially inseminated and assigned to receive daily injections of 50 mg progesterone from 2 to 14 d (n = 31), 4 to 14 d (n = 26) or to serve as controls and receive injections of oil from 2 to 14 d (n = 28). Gilts were slaughtered 25 to 28 d after breeding for determination of embryo survival. Supplemental progesterone had no effect on embryo survival. Key words: Gilt, embryo, progesterone
Intake, digestibility, methane and heat production in bison, wapiti and white-tailed deer
Authors: Galbraith J. K. , Mathison G. W. , Hudson R.J. , McAllister T. A. , Cheng K.-J.
Published: March 2010

A 3 × 2 factorial experiment was conducted in which the digestibility of alfalfa pellets and methane and heat productions were measured in bison, wapiti and white-tailed deer in February/March 1995 and in April/May 1995. Voluntary dry matter intake (DMI) while animals were individually fed averaged 70, 87 and 68 g kg−0.75 d−1, respectively (P = 0.05), and was generally higher in April/May than in February/March. Corresponding organic digestibilities were 52.9, 54.1 and 49.1% (P = 0.10). There was also a trend (P < 0.1) for fiber digestibilities to be lowest for deer. Methane production (L kg−1 DMI), was 30.1, 23.5, and 15.0 L kg−1 for bison, wapiti and deer, respectively (P = 0.01), with more (P < 0.01) methane being produced in February/March than in April/May (28 vs. 18 L kg−1 DMI). No differences in heat production (kJ kg−0.75) or estimated energy requirements for maintenance could be detected between species, although animals numerically produced 40% more heat (881 vs. 632 kJ kg−0.75, P = 0.13) in April/May when feed intakes were higher than in February/March. It was concluded that DMI of native ungulates is higher in spring than winter and that methane emissions per unit feed consumed were the highest with bison and the least with white-tailed deer. Key words: Bison, deer, wapiti, digestibility, methane, calorimetry
Evaluation of ultrasound measurements of fat thickness and longissimus muscle area in feedlot cattle: Assessment of accuracy and repeatability
Authors: Hassen A. , Wilson D. E. , Willham R. L. , Rouse G. H. , Trenkle A. H.
Published: March 2010

Data from two cattle feeding trials were used to estimate accuracy and repeatability of ultrasound measurements of 12–13th rib fat thickness and longissimus muscle area. In each trial, images from the last scan prior to slaughter were interpreted by two certified technicians. Each technician interpreted the image of each steer twice on two different days. Overall technician biases for ultrasound measurements of fat thickness and longissimus muscle area were −0.17 cm and 0.63 cm2, respectively. Mean bias in measurement of fat thickness by the two technicians was similar in amount and direction (−0.14 cm vs. −0.20 cm); however, bias in the measurement of longissimus muscle area by the two technicians took an opposite direction (−1.28 cm2 vs. 2.54 cm2). Repeatability of ultrasound-measured fat thickness was the same for both technicians (0.96 to 0.97). However, measurements of technician A showed a better repeatability (0.92) than technician B (0.79) for ultrasound-measured longissimus muscle area. Generally, except for minor differences, degree of experience did not show a consistent difference in the accuracy of ultrasound estimation of fat thickness and longissimus muscle area. Hence, it was concluded that technicians could easily be trained to make accurate predictions of fat thickness and longissimus muscle area. Key words: Beef cattle, carcass, ultrasound, repeatability, accuracy
Relative efficacy of inocula from rumen fluid or faecal solution for determining in vitro digestibility and gas production
Authors: El-Meadaway A. , Mir Z. , Mir P. S. , Zaman M. S. , Yanke L. J.
Published: March 2010

Three experiments were conducted to study the effects of substituting rumen fluid (RF) with faecal suspension (FS) as an inoculum for determination of in vitro dry matter digestibility (IVDMD, experiment 1) and gas production (exp. 2). Barley grain (BG), Persian clover (PC), alfalfa (ALF), bromegrass (BR) and barley straw (BS) were used to evaluate the efficacy of the two inocula. In exp. 1, IVDMD was determined using RF or FS containing 3, 6 and 9% fresh cattle faeces as inocula. Except for BS, IVDMD values obtained with either RF or FS containing 3% faeces were not different (P > 0.05). In contrast, FS containing 6 or 9% faeces resulted in lower (P < 0.05) IVDMD than those obtained with RF. Total VFA, butyric and valeric acids of in vitro supernatant were higher (P < 0.05) in RF than FS incubated buffers. Molar proportions of acetic and propionic acids were variable among feeds. Mean acetic:propionic ratio was similar (except for BG) for RF or FS. In exp. 2, substitution of RF with FS containing 6, 11 or 16% cattle faeces as inoculum generally resulted in an increased lag time for four feeds (PC was not included). The rate of gas production was lower when FS was used instead of RF for ALF and BR. For BG however, use of FS resulted in a higher (P < 0.05) rate of gas production than when RF was used. Total gas production values were similar within all the feeds regardless of the source of inoculum. In experiment 3, the relative size of the total and cellulolytic populations were higher for RF than for FS, with a greater diversity of genera of bacteria isolated from RF. Results from this study indicate that FS has the potential to be used instead of RF to obtain IVDMD and gas production for BG and forage hay but not for poor quality roughages such as BS. However, more research with FS is required to confirm these findings. Key words: IVDMD, gas production, rumen fluid, faecal suspension
Shearing force of alfalfa stems: Effects of genotype and year interactions
Authors: Iwaasa A. D. , Beauchemin K. A. , Acharya S. N. , Buchanan-Smith J. G.
Published: March 2010

Shearing force of alfalfa (Medicago sativa L.) stems was measured to evaluate genotype-by-year interactions. Based on mean shearing force for each stem segment and genotype clustering criteria, several genotypes had similarly shearing forces among years. Therefore, selecting genotypes with desirable shearing force characteristics to improve digestibility or intake potential of forages may be possible. Key words: Genotype, environment, shearing force, cell wall chemical constituents
Impact of the halothane gene on muscle quality and pre-slaughter deaths in Western Canadian pigs
Authors: Murray A.C. , Johnson C. P.
Published: March 2010

The genotype with respect to the point mutation at position 1843 of the ryr-1 gene (halothane gene) and longissimus muscle quality of 1006 pigs in two Western Canadian packing plants was assessed to determine the frequency of this mutation within the commercial population and the relationship of genotype to the frequency of PSE (pale, soft, exudative) pork. The frequencies of nn (homozygous carrier), Nn (heterozygous carrier) and NN (homozygous normal) pigs within the commercial population were 0.3, 9.4 and 90.3%, respectively. Based on the subjective pork quality standards of Agriculture and Agri-Food Canada, the frequencies of paler-than-normal (colour score < 3) and darker-than-normal pork (colour score > 3) were 21.7 and 11.2%, respectively. The frequencies of soft, exudative pork (structure score < 3) and firm dry pork (structure score > 3) were 14.8 and 7.6%, respectively. The frequency of pale loin colour was 80 and 20% higher for Nn than for NN pigs in the two packing plants, whereas the frequency of dark pork was unaffected by genotype. Nn pigs exhibited a twofold higher incidence of soft, exudative pork than did NN pigs, but because of their very low frequency in the commercial kill, had a very small impact on the overall incidence of soft, exudative pork. Removing this mutation from the pig population would have very little impact on the frequency of pale or soft, exudative pork within the two packing plants involved in this study. Determination of the halothane genotype of 401 pigs, arriving dead or dying at the packing plants, indicated that pigs of the nn, Nn and NN genotypes were responsible for 27.7, 25.2 and 47.1% of deaths. The frequency of deaths within the nn, Nn and NN genotypes was estimated to be 9.2, 0.27 and 0.05%, respectively. Approximately 90% of the PSE condition in Western Canada is caused by factors other than the halothane gene, but this gene has a major negative influence on the frequency of pre-slaughter deaths. Key words: Halothane gene, PSS, malignant hyperthermia, pork quality, swine deaths