Young Beef Research Articles

Associations of blood parameters with age, feed efficiency and sampling routine in young beef bulls

Utilization of blood parameters as proxies for feed efficiency is an avenue to maximize profitability of the beef industry. Among other factors, age and sampling routine may impact the reliability of potential proxies for residual feed intake (RFI). Thus, the objectives were to assess associations of blood parameters with age and RFI under two sampling routines. Thirty-two crossbred bulls with an average body weight (BW) of 633±93kg and 369±29 days of age were studied. Residual feed intake was calculated using average daily gain, BW and ultrasound traits for body composition. Seven blood samples for each bull were collected during a 33-day on-station sampling period and an additional sample was collected at slaughter for analysis of blood metabolites and hormones. Bulls were classified as younger (342±17 days of age) and older (395±4 days of age) and into efficient (−0.55±0.70kg DM/day) and inefficient (RFI=0.55±0.29kg DM/day). Means of blood parameters were compared between age and feed efficiency groups using a mixed model for on-station sampling and a general linear model for slaughter sampling. During the on-station sampling, glucose (P=0.01), potassium (P=0.01) and insulin-like growth factor 1 (P=0.01) were lesser in older bulls while urea (P=0.05), acetate (P=0.01), osmolality (P=0.01), testosterone (P=0.01) and follicle stimulating hormone (FSH; P=0.04) were greater in older bulls. At slaughter, carbon dioxide (P=0.01), brain-derived neurotrophic factor (P=0.05) and FSH (P=0.01) were greater in older bulls. Over the on-station sampling, osmolality (P=0.05) was greater in inefficient bulls while leptin (P=0.01) was greater in efficient bulls. On the day of slaughter, cholesterol (P=0.04) and alkaline phosphatase (P=0.04) were lesser in efficient bulls. Age and RFI classes interaction was observed for T3 (P=0.01) during the on-station sampling where lesser T3 blood levels where observed in efficient bulls within the younger group (P=0.01) and in older bulls within the inefficient group (P=0.05). Overall, these results support the association of blood parameters with variation in age and RFI and illustrate the impact of sampling routine on components of intermediary metabolism in yearling bulls, providing information to the development of proxies for RFI.

National Survey of Shiga Toxin–Producing Escherichia coli Serotypes O26, O45, O103, O111, O121, O145, and O157 in Australian Beef Cattle Feces

Escherichia coli O157 and six non-O157 Shiga toxin-producing E. coli (STEC) serotypes (O26, O45, O103, O111, O121, and O145, colloquially referred to as the "big 6") have been classified as adulterants of raw nonintact beef products in the United States. While beef cattle are a known reservoir for the prototype STEC serotype, E. coli O157, less is known about the dissemination of non-O157 STEC serotypes in Australian cattle. In the present study, 1,500 fecal samples were collected at slaughter from adult (n =628) and young (n =286) beef cattle, adult (n =128) and young (n =143) dairy cattle, and veal calves (n = 315) across 31 Australian export-registered processing establishments. Fecal samples were enriched and tested for E. coli O157 and the big 6 STEC serotypes using BAX System PCR and immunomagnetic separation methods. Pathogenic STEC (pSTEC; isolates that possess stx, eae, and an O antigen marker for O157 or a big 6 serotype) were isolated from 115 samples (7.7%), of which 100 (6.7%) contained E. coli O157 and 19 (1.3%) contained a big 6 serotype. Four of the 115 samples contained multiple pSTEC serotypes. Among samples confirmed for big 6 pSTEC, 15 (1%) contained E. coli O26 and 4 (0.3%) contained E. coli O111. pSTEC of serotypes O45, O103, O121, and O145 were not isolated from any sample, even though genes indicative of E. coli belonging to these serotypes were detected by PCR. Analysis of animal classes revealed a higher pSTEC prevalence in younger animals, including veal (12.7%), young beef (9.8%), and young dairy (7.0%), than in adult animals, including adult beef (5.1%) and adult dairy (3.9%). This study is the largest of its kind undertaken in Australia. In contrast to E. coli O157 and consistent with previous findings, this study reports a relatively low prevalence of big 6 pSTEC serotypes in Australian cattle populations.

Genetic parameters for both a liver damage phenotype caused by and antibody response to phenotype in dairy and beef cattle.

is a helminth parasite of economic importance to the global cattle industry, with documented high international herd prevalence. The objective of the present study was to generate the first published genetic parameter estimates for liver damage caused by as well as antibody response to in cattle. Abattoir data on the presence of live , or -damaged livers, were available between the years 2012 and 2015, inclusive. A second data set was available on cows from 68 selected dairy herds with a blood ELISA test for antibody response to in autumn 2015. Animals were identified as exposed by using herd mate phenotype, and only exposed animals were retained for analysis. The abattoir data set consisted of 20,481 dairy cows and 75,041 young dairy and beef animals, whereas the study herd data set consisted of 6,912 dairy cows. (Co)variance components for phenotypes in both data sets were estimated using animal linear mixed models. Fixed effects included in the model for both data sets were contemporary group, heterosis coefficient, recombination loss coefficient, parity, age relative to parity/age group, and stage of lactation. An additional fixed effect of abattoir by date of slaughter was included in the model for the analysis of the abattoir data. Direct additive genetic effects and a residual effect were included as random effects for all analyses. After data edits, the prevalence of liver damage caused by in cows and young cattle was 47% and 20%, respectively. The prevalence of a positive antibody response to in cows from the study herd data was 36% after data edits. The heritability of as a binary trait for dairy cows in abattoir data and study herd data was 0.03 ± 0.01 and 0.09 ± 0.02, respectively; heritability in young cattle was 0.01 ± 0.005. The additive genetic SD of as a binary trait was 0.069 and 0.050 for cows and young cattle from the abattoir data, respectively, and 0.112 from the study herd cows. The genetic correlation between liver damage caused by in young cattle and cows from the abattoir data was 0.94 ± 0.312 and the genetic correlation between liver damage caused by in cows and positive antibody response to in cows in the study herd data was 0.37 ± 0.283.

1259 Beta-hydroxybutyrate concentration influences conception date in young beef cows in Tennessee

1259 Beta-hydroxybutyrate concentration influences conception date in young beef cows in Tennessee

Effect of 17β-estradiol administration on hepatic expression of glutamine synthetase, β-catenin, and GPR30 in young and aged beef cows

To test the hypothesis that increased circulating estradiol increases hepatic glutamine synthetase (GS) content in young and aged cows, and two nonclassical nongenomic estradiol pathway intermediat...

Relationship of sexual development and fertility-related measures in young beef bulls with known feed efficiency

Relationship of sexual development and fertility-related measures in young beef bulls with known feed efficiency

Seminal plasma protein concentrations vary with feed efficiency and fertility-related measures in young beef bulls

Fertility-associated proteins (FAP) found in seminal plasma indicate sexual maturity, which appears to be influenced by feed efficiency in cattle. This study characterized FAP via proteomics and verified associations of these proteins with feed efficiency, body composition and fertility-related measures in yearling beef bulls. Assessments including testicular ultrasonography, infrared thermography, seminal quality, seminal plasma proteomics, carcass composition, and reproductive organ biometry were obtained. From a population of 31 bulls, the seven most and least feed efficient (efficient, inefficient) bulls were used for categorical comparisons. Correlations between FAP, productive performance and fertility-related measures were determined. These traits were also correlated with orthogonal factors summarized from the FAP. Efficient bulls had increased epididymal sperm-binding protein-1 and decreased concentration of protein-C inhibitor compared to inefficient bulls. Correlations between FAP with age, body size, body composition, reproductive organ biometry, scrotal temperature, and seminiferous tubule maturity are reported. Acrosin and cathepsin D increased with development of the testes and osteopontin increased with greater numbers of mature seminiferous tubules. Phosphoglycerate kinase-2 was higher in animals with a higher scrotum temperature and a higher prevalence of sperm morphology defects. The principal factor indicated that FAP variability concentrations were positively correlated with age, reproductive organ biometry, body size and composition. Our results indicate that FAP changes with body size and sexual development, and demonstrates differences in the proteomics of bulls with diverging feed efficiency. This is related to the delay in the sexual maturity of efficient young bulls.

Production and quality of beef from young bulls fed diets supplemented with peanut cake

Peanut cake is a biodiesel byproduct that has been tested as an alternative feed additive for use in cattle production. This study aimed to assess the importance of dietary peanut cake inclusion for young bull growth rate, beef production, and beef quality. In total, 32 Nellore young bulls individually housed in stalls with a mean initial body weight of 390±43.5kg were distributed in a completely randomized design for the experiment. The animals were fed Tifton 85 hay and one of four concentrate mixtures with 0, 33, 66 or 100% peanut cake instead of soybean meal. There was a linear reduction (P<0.05) in the slaughter weight and hot carcass weight and a quadratic effect (P<0.05) on the beef texture. No alterations occurred in the physicochemical characteristics of the longissimus thoracis; however, changes were observed (P<0.05) in the longissimus thoracis fatty acid profile. The replacement of soybean meal with peanut cake at levels up to 100% in the diet of feedlot-finished young bulls promotes a beneficial increase in the levels of PUFAs and the following nutraceutical compounds: conjugated linoleic acid (CLA) and Ω3 and Ω6 fatty acids.

Associations between feed efficiency, sexual maturity and fertility-related measures in young beef bulls

The beef industry has emphasized the improvement of feed utilization, as measured by modeling feed intake through performance traits to calculate residual feed intake (RFI). Evidence supports an inverse relationship between feed efficiency and reproductive function. The objective of this study was to determine the relationship of reproductive assessments and RFI unadjusted (RFIKoch) or adjusted for body composition (RFIus) and the relationship among fertility-related parameters. In total, 34 crossbred bulls were housed together for 112 days of performance evaluation, followed by assessment of scrotum IR imaging, scrotal circumference, testes ultrasonography and semen quality parameters at 377±33.4 days of age. Bulls were slaughtered at 389±34.0 days of age, and analyses of carcass composition, biometrics and histomorphometry of the testis and epididymis were conducted. Bulls were grouped into two subpopulations based on divergence of RFI, and within each RFI model either by including 50% of the population (Halves, high and low RFI, n=17) or 20.6% extremes of the population (Tails, high and low RFI, n=7). The means of productive performance and fertility-related measures were compared through these categories. Pearson’s correlation was calculated among fertility-related measures. In the Halves subpopulation of the RFIus, sperm of low-RFI bulls had decreased progressive motility (47.30% v. 59.90%) and higher abundance of tail abnormalities (4.30% v. 1.80%) than that of high-RFI bulls. In the Tails subpopulation of the RFIKoch, low RFI displayed less variation in the scrotum surface temperature (0.62°C v. 1.16°C), decreased testis echogenicity (175.50 v 198.00 pixels) and larger (60.90 v. 56.80 mm2) but less-developed seminiferous tubules than high-RFI bulls. The evaluation of fertility-related parameters indicated that a higher percentage of immature seminiferous tubules was correlated with occurrence of sperm with distal droplets (r=0.59), a larger temperature variation at the top of the scrotum was correlated with improved sperm progressive motility (r=0.38), a lower occurrence of sperm loose head abnormalities was correlated with larger temperature variation at the lower part of the scrotum (r=−0.43), and a lower minimum testis echogenicity (r=−0.59) and smaller scrotal circumference (r=0.72) were correlated with age. The adjustment for body composition (RFI determination) enabled distinct biological inferences about reproduction and feed efficiency when compared with the non-adjusted model. However, both RFI models and the correlation analysis supported the hypothesis that feed-efficient bulls have features of delayed sexual maturity. Overall, the assessment of fertility-related measurements is important to avoid the improvement of feed efficiency at the expense of reproductive function in young bulls.

Prevalent Parasitosis in Beef and Dairy Cattle Farms in Vidzeme Region

Abstract The aim of the study was to investigate the beef and dairy cow parasitosis epizootic situation in Vidzeme region. Research was done throughout Vidzeme territory during the period of the years 2013-2014. The total number of animals examined was: 273 dairy and 90 young beef cattle aged from 6 months to two years and 248 dairy and 29 beef cows older than two years. For the diagnosis of helminthes standardized ovoscopic and larvoscopic methods were used. For the diagnosis of protozoa flotation and modified Ziehl-Neelsen methods were used. The main species in the samples were Cryptosporidium spp., Eimeria spp. and Strongylus spp. In the young dairy and beef cattle aged from 6 months to two years and cattle older than two years Cryptosporidium spp. invasion accordingly was 32.6% and 19% (dairy cattle) and 62.2% and 65.5% (beef cattle); the invasion of Eimeria spp. 30% and 7.3% (dairy cattle) and 55.6% and 10.3% (beef cattle); and the invasion of Strongylus spp. was 17.6% and 13.7% (dairy cattle) and 43.3% and 27.6% (beef cattle). Both dairy and beef cattle were infected with Moniezia spp., Paramphistomum spp., Strongyloides spp. Dairy cows aged from 6 months to two years had Trichuris spp., Dictyocaulus spp. and Neoscaris spp. invasion.

Prevalence of bovine herpes virus type 1 in small herds of young beef cattle in south-eastern Poland – a preliminary study

Abstract The study was performed on nasal swabs, tracheal samples, and sera obtained from young beef heifers aged between 6 and 12 months, from farms in eastern and south-eastern Poland. The samples were evaluated using bovine herpesvirus 1 (BHV-1) ELISA kits (ELISA BHV1 antibody and ELISA BHV1 antigen) and PCR. Among all the animals examined, 37 (32.2%) were positive in the ELISA BHV1 antigen test. The presence of BHV-1 was confirmed by PCR in 42 (36.5%) animals. In the ELISA BHV1 antibody test, 39 (33.9%) seropositive animals were identified. The presence of BHV-1 positive samples was observed in all the examined breeds of young cattle. There were no significant differences (P ≤ 0.05) in BHV-1 positive samples. The results indicate that the incidence of BHV-1 infections in feedlot cattle herds studied was 32.2%-36.5%, which suggests that preventive measures should be implemented in order to limit transmission of the virus.

BILL E. KUNKLE INTERDISCIPLINARY BEEF SYMPOSIUM: Does tall fescue toxicosis negatively impact bull growth and breeding potential?

The predominant cool-season forage in the southeastern United States is the tall fescue cultivar Kentucky 31 (KY31). Kentucky 31 possesses an endophyte (), which produces a family of toxins called ergot alkaloids. These toxins negatively affect the physiology of animals on consumption and result in the syndrome known as fescue toxicosis. Currently, the United States annually produces approximately 11.4 billion kg of beef, of which 25% originates in the southeastern region of the United States where forage systems frequently are tall fescue based. Cattle within this forage system exhibit reduced gains and reproductive performance. The result is a reduction in the nation's beef supply with annual revenue losses recently estimated at approximately US$1 billion. Our hypothesis is that exposure to these ergot alkaloids in conjunction with limited availability of nutrients decreases bull semen quality and fertility. Although the literature is clear that these toxins affect BW, body temperature, blood flow, hair growth, and female reproduction in cattle, their effect on bull reproduction and the mechanisms through which the toxins act are not well defined. Six studies published from 2004 to 2015 assessed bull growth, body composition, and semen quality of young beef bulls exposed to ergot alkaloids. If semen quality or fertility is altered, the mechanisms involved may be either direct effects of ergot alkaloids through neurotransmitter receptors or indirect effects such as inhibiting the release of prolactin (PRL). The possible effects of ergot alkaloids or PRL require establishing the presence or absence of dopamine, adrenergic, serotonin, or PRL receptors in the testis, epididymis, and sperm cell of the bull. The objective of this review is to relate our findings to the few previous studies conducted that evaluated the impact of fescue toxicosis on bull reproduction and to propose possible mechanisms of action for lowered semen quality.

A trend analysis of antimicrobial resistance in commensal Escherichia coli from several livestock species in Belgium (2011–2014)

A temporal trend analysis was performed on antimicrobial resistance data collected over 4 consecutive years (2011–2014) in the official Belgian antimicrobial resistance monitoring programme. Commensal Escherichia coli strains were isolated from faecal samples of four livestock categories (veal calves, young beef cattle, broiler chickens and slaughter pigs) and the trends of resistance profiles were analysed. The resistance prevalence remained high (>50%) during the study period for ampicillin in veal calves and chickens, for ciprofloxacin and nalidixic acid in chickens, for sulfamethoxazole in veal calves, chickens and pigs and for tetracycline in veal calves. Using logistic regression and Generalized Estimating Equation and after p value adjustment for multiple testing (Linear step-up method), statistically significant decreasing temporal trends were observed for several of the 11 tested antimicrobials in several livestock categories: in veal calves (10/11), in chickens (6/11) and in pigs (5/11). A significant increasing trend was observed for the prevalence of resistance to ciprofloxacin in chickens. Multi-resistance, considered as the resistance to at least three antimicrobials of different antibiotic classes, was observed in the four livestock categories but was significantly decreasing in veal calves, chickens and pigs. Overall, the prevalence of resistance and of multi-resistance was lowest in the beef cattle livestock category and highest in broiler chickens. These decreasing temporal trends of antimicrobial resistance might be due to a decrease of the total antimicrobial consumption for veterinary use in Belgium which was reported for the period between 2010 and 2013. The methodology and statistical tools developed in this study provide outputs which can detect shifts in resistance levels or resistance trends associated with particular antimicrobial classes and livestock categories. Such outputs can be used as objective evidence to evaluate the possible efficacy of measures taken by animal health authorities and stakeholders in the livestock sector to limit antimicrobial resistance occurrence.

Glutamine synthetase and alanine transaminase expression are decreased in livers of aged vs. young beef cows and GS can be upregulated by 17β-estradiol implants.

Aged beef cows (≥ 8 yr of age) produce calves with lower birth and weaning weights. In mammals, aging is associated with reduced hepatic expression of glutamine synthetase (GS) and alanine transaminase (ALT), thus impaired hepatic Gln-Glu cycle function. To determine if the relative protein content of GS, ALT, aspartate transaminase (AST), glutamate transporters (EAAC1, GLT-1), and their regulating protein (GTRAP3-18) differed in biopsied liver tissue of (a) aged vs. young (3 to 4 yr old) nonlactating, nongestating Angus cows (Exp. 1 and 2) and (b) aged mixed-breed cows with and without COMPUDOSE (17β-estradiol) ear implants (Exp. 3), Western blot analyses were performed. In Exp. 1, 12 young (3.62 ± 0.01 yr) and 13 aged (10.08 ± 0.42 yr) cows grazed the same mixed forage for 42 d (August-October). In Exp. 2, 12 young (3.36 ± 0.01 yr) and 12 aged (10.38 ± 0.47 yr) cows were individually fed (1.03% of BW) a corn-silage-based diet to maintain BW for 20 d. For both Exp. 1 and 2, the effect of cow age was assessed by ANOVA using the MIXED procedure of SAS. Cow BW did not change ( ≥ 0.17). Hepatic ALT (78% and 61%) and GS (52% and 71%) protein content (Exp. 1 and 2, respectively) was decreased ( ≤ 0.01), whereas GTRAP3-18 (an inhibitor of EAAC1 activity) increased ( ≤ 0.01; 170% and 136%) and AST, GLT-1, and EAAC1 contents did not differ ( ≥ 0.17) in aged vs. young cows. In Exp. 2, free concentrations (nmol/g) of Glu, Ala, Gln, Arg, and Orn in liver homogenates were determined. Aged cows tended to have less ( = 0.10) free Gln (15.0%) than young cows, whereas other AA concentrations did not differ ( 0.26). In Exp. 3, 14 aged (> 10 yr) cows were randomly allotted ( = 7) to sham or COMPUDOSE (25.7 mg of 17β-estradiol) implant treatment (TRT), and had ad libitum access to alfalfa hay for 28 d. Blood and liver biopsies were collected 14 and 28 d after implant treatment. Treatment, time after implant (DAY), and TRT × DAY effects were assessed by ANOVA using the MIXED procedure of SAS. Cow BW was not affected ( ≥ 0.96). Implant increased ( ≤ 0.02) total plasma estradiol by 220% (5.07 vs. 1.58 pg/mL) and GS protein by 300%, whereas the relative content of other proteins was not altered ( ≥ 0.16). We conclude that hepatic expression of ALT and GS are reduced in aged vs. young cows, and administration of 17β-estradiol to aged cows increases plasma estradiol and hepatic GS, but not that of other proteins that support hepatic Glu metabolism.

Detection of the bovine viral diarrhoea virus (BVDV) in young beef cattle in eastern and south-eastern regions of Poland.

In view of the scarcity of information concerning viral diarrhoea virus (BVDV) infections in beef cattle in Poland, the aim of this study was to evaluate the presence of the BVDV in young beef cattle from selected herds in eastern and south-eastern regions of Poland. The material consisted of 78 sera obtained from beef cattle from 15 farms, aged 6-12 months. The anti-BVDV antibody level in the sera was estimated with an ELISA kit, and detection of the BVDV was carried out by standard PCR and one step Real-Time RT-PCR. The ELISA results showed a high degree (80%) of positivity in 5 of the 78 samples. In 7 samples the degree of positivity was in the very low range: < 40%. Of the 78 cDNA samples, the presence of genetic material with a length of 288 bp was found by standard PCR in 3 sera. The genetic material of BVDV was also found in the sera of the same three calves by Real-Time HRM PCR. BVDV infection in young beef cattle in south-eastern Poland is not a significant problem. This was confirmed by the positive ELISA results for 6.4% of the animals and the positive PCR results for 3.9%. The percentage of positive beef herds was about 8.6%. However, due to the severe nature of the disease and rapid transmission of the virus, regular monitoring of BVDV should be carried out.

Prevalence of carriage of Shiga toxin-producing Escherichia coli serotypes O157:H7, O26:H11, O103:H2, O111:H8, and O145:H28 among slaughtered adult cattle in France.

The main pathogenic enterohemorrhagic Escherichia coli (EHEC) strains are defined as Shiga toxin (Stx)-producing E. coli (STEC) belonging to one of the following serotypes: O157:H7, O26:H11, O103:H2, O111:H8, and O145:H28. Each of these five serotypes is known to be associated with a specific subtype of the intimin-encoding gene (eae). The objective of this study was to evaluate the prevalence of bovine carriers of these “top five” STEC in the four adult cattle categories slaughtered in France. Fecal samples were collected from 1,318 cattle, including 291 young dairy bulls, 296 young beef bulls, 337 dairy cows, and 394 beef cows. A total of 96 E. coli isolates, including 33 top five STEC and 63 atypical enteropathogenic E. coli (aEPEC) isolates, with the same genetic characteristics as the top five STEC strains except that they lacked an stx gene, were recovered from these samples.O157:H7 was the most frequently isolated STEC serotype. The prevalence of top five STEC (all serotypes included) was 4.5% in young dairy bulls, 2.4% in young beef bulls, 1.8% in dairy cows, and 1.0% in beef cows. It was significantly higher in young dairy bulls (P<0.05) than in the other 3 categories. The basis for these differences between categories remains to be elucidated. Moreover,simultaneous carriage of STEC O26:H11 and STEC O103:H2 was detected in one young dairy bull. Lastly, the prevalence of bovine carriers of the top five STEC, evaluated through a weighted arithmetic mean of the prevalence by categories, was estimated to 1.8% in slaughtered adult cattle in France.

Detection of bovine respiratory syncytial virus infections in young dairy and beef cattle in Poland

Background: Bovine respiratory syncytial virus (BRSV) is a major contributor to bovine respiratory disease complex in dairy and beef calves, especially during the first year of life. There is a lack of comprehensive information about the prevalence of infection in cattle herds in Poland as well as in European countries outside the European Union.Objective: The aim of this study was to estimate the prevalence of BRSV infections in young beef and dairy cattle in southeastern Poland, a region that has direct contact with non-EU countries.Animals & methods: Nasal swabs and sera (n = 120) were obtained from young cattle aged 6–12 months from 45 farms in eastern and southeastern Poland. BRSV antigen detection in the nasal swabs was carried out using a rapid immunomigration assay used in diagnosing human respiratory syncytial virus (hRSV) infections in humans, while antibodies to BRSV were detected in the sera by ELISA antibody detection.Results: The study confirmed the presence of BRSV infections in young cattle under 12 months of age from both dairy and beef herds. BRSV was detected in 27 of the 45 herds (60%) sampled.Conclusions: Findings from this study indicate a high prevalence of BRSV infections in cattle in Poland, which may have a significant influence on health status and animal performance. The prevalence of infection is similar to that in other parts of Poland and other countries in Europe. Development of strategies to reduce BRSV infections is needed to improve health and productivity.

Effects of injectable fat-soluble vitamins and selenium on serum status in young beef calves

Crossbred beef calves (age 3 to 20 days) were used to determine effects of injectable vitamins on serum concentrations of selenium, vitamin A (retinol), and vitamin E (alpha-tocopherol). Spring-born calves were assigned to 1 of 4 treatments: (1) no treatment (Control, n=10); (2) 4 mL of a product containing selenium and vitamin E (SE, n=10); (3) 5 mL of a product containing vitamin E, vitamin A, and vitamin D (EAD, n=10); or (4) 4 mL SE and 5 mL EAD (Both, n=10). Blood samples were taken from calves immediately prior to (day 0) and 48 hours after treatment, and from their dams on day 0. Concentrations of selenium, vitamin A, and vitamin E in the dams were 112.8 ng/mL, 0.21 æg/mL, and 2.84 æg/mL, respectively. Calves administered SE (70.3 ng/mL) or Both (72.9 ng/mL) had greater (P&lt;0.05) concentrations of selenium on day 2 compared with Control (57.2 ng/mL) or EAD (56.0 ng/mL) calves. Calves administered EAD (0.21 æg/mL) or Both (0.22 æg/mL) had greater (P&lt;0.05) concentrations of vitamin A compared with SE (0.17 æg/mL) or Control calves (0.15 æg/mL). Calves administered EAD (13.8 æg/mL) or Both (15.0 æg/mL) had greater (P&lt;0.05) concentrations of vitamin E compared with SE (6.2 æg/mL) or Control calves (3.4 æg/mL). Administration of injectable EAD increased serum concentration of vitamin A and vitamin E in young beef calves, whereas SE increased concentrations of selenium. Neither duration nor clinical significance of increased concentrations of vitamins and selenium were investigated.

A Survey on Feedlot Performance of Purebred and Crossbred European Young Bulls and Heifers Managed Under Intensive Conditions in Veneto, Northeast Italy

This study, based on a nearly 10-year collection of performance data of young bulls and beef heifers, aimed to benchmark production traits of specialized fattening herds of northern Italy and to compare the performance of stock calves belonging to several European genetic types (GT). Data originated from 2806 batches (a group of stock calves homogeneous for GT, origin, finishing herd, fattening period, and diets), and concerned 188,891 animals of 10 GT herded in 44 farms of the Veneto region. For each batch, average body weight (BW) at arrival and at sale, duration of the fattening period, losses due to injury or death, purchase and sell price were collected, and average daily gain (ADG) and net sale gain (NSG) per head, per day of fattening, and per kg of BW gain were computed. Charolais and Limousine young bulls accounted for nearly 50% and 20%, respectively, of all animals, and over 90% of calves originated from France. Average BW at arrival and at slaughter approximated 370 and 650 kg, respectively, and ADG approached 1.30 kg/d, but variation due to GT was large (P<0.01). Charolais young bulls were the heaviest at slaughter and showed the greatest ADG, whereas Irish crosses produced the highest NSG per head and per day of fattening. Year affected all traits (P<0.01), but his magnitude was limited for BW at purchase or sale and for ADG, and slightly larger for NSG, even if this last trait did not evidence any long period congruent trend.

Physicochemical Meat Quality, Fatty Acid and Free Amino Acid Composition of Strip loin, Chuck Tender, and Eye of Round Produced by Different Age Groups of Hanwoo Cow

This study was performed to investigate the influence of age on the physicochemical properties of strip loin (m. longissimus lumborum), chuck tender (m. supraspinatus), and eye of round (m. semitendinosus) of Hanwoo cows. Hanwoo cows (n=126; 24-194 mon; live weight, 270-500 kg) were slaughtered and three muscles were obtained according to 3 age groups (G1, 9 years old). The chuck tender had significantly higher protein contents in G3 than in G1 or G2 (p<0.05). For strip loin and chuck tender, G1 had significantly higher intramuscular fat contents than G3 (p<0.05). The chuck tender had significantly higher b* (yellowness) values for G2 than for G1 (p<0.05). The three muscles had significantly higher cooking loss (%) and lower WHC (%) in G3 than in G1 or G2 (p<0.05). WBS values of strip loin were significantly higher in G3 than in the other groups (p<0.05). The three muscles had higher C18:1n9 in G1 than that in the other groups. The total content of saturated fatty acids was significantly higher in G3 than in G1 for all 3 muscles (p<0.05). Regarding free amino acid contents, G1 had significantly higher contents of threonine, alanine, valine, methionine, phenylalanine, leucine, and lysine in the strip loin than G2 or G3 (p<0.05). In conclusion, young cow beef were higher in the WHC, intramuscular fat and free amino acids contents, whereas old cow beef had higher cooking loss and WBS (p<0.05).