Effects of feeding corn silage, pelleted, ensiled, or pelleted and ensiled alfalfa on growth and carcass characteristics of lamb

Two experiments were conducted to evaluate the effects of corn silage (CS) and alfalfa (pelleted (AP), haylage (AH), or combination (APH)) on lamb growth and carcass characteristics. The objective of Experiment 1 (Exp. 1) was to compare AH to CS in lamb feedlot diets on lamb growth and carcass characteristics. Eighty lambs were used in a 56 day experiment with a randomized complete block design. The objective of Experiment 2 (Exp. 2) was to determine the effects of alfalfa form, AP, AH or AHP, on animal performance and carcass characteristics. Seventy two lambs were used in an 82 day experiment with a randomized complete block design. In Exp. 1, lambs offered AH consumed 23.5% more feed on a daily basis than lambs offered CS. However, lambs fed CS gained weight 21.3% faster than lambs fed AH (259 versus 213 g/day, respectively). Additionally, lambs fed CS were 50.4% more efficient in converting feed to gain compared with lambs offered AH (0.173 versus 0.115 kg gain/kg feed, respectively). In Exp. 2, AP resulted in a greater dry matter intake (DMI) and average daily gain (ADG), and fewer days on feed than with AH. The combination of pellets + haylage resulted in a greater DMI, ADG, and fewer days on feed compared to AH alone. Therefore, there was an inverse relationship between both forage particle size and diet moisture content with DMI. There was no difference in daily efficiency of gain due to the form of alfalfa. Average daily gain, days on feed, and DMI are economically important criteria that differ due to the form of alfalfa even when feed efficiencies are similar

Meat quality of grain finished entire male Bos indicus cattle

Although the utilisation of young, entire male cattle for premium beef production is common in many parts of the world, it is not widely practiced in Australia. This study examined the carcass characteristics and eating quality of meat from entire 80S indicus males sourced from northern breeding herds and grain finished. Entire male calves were weighed and allocated to one of\ud four (4) treatment groups: 1) Early-castrate (n=140); 2) Late-castrate (n=136); 3) Short-scrotum (n=121); 4) Entire (n=129). At =200 kg liveweight, all calves were weaned and those in Group 2 were castrated. The weaners were grown out on grass pasture to =330 kg liveweight, at which time they were sent to a feedlot and grain fed for 75 days, to =420 kg liveweight, prior to slaughter at 25 to 28 months of age. Data collected included carcass (weight, grade, gross value, butt shape, dentition, P8 fat depth, bruise score), MSA grading and meat quality data. Three muscles, eye round (M. semitendinosus), rump (M. gluteus medius) and striploin (M. longissimus dorsi lumborum) from thirty animals in each treatment group were used to generate consumer taste panel sensory test MQ4 scores. Carcasses from non-castrated animals that met the target AusMeat specification for "male" had a =$52 higher gross value than did those from castrated animals. Although meat from castrated animals had higher MQ4 scores than did meat from non-castrated animals, there were no differences between the boning groups for any of the sensory test outcomes, and, of the three muscles that were sensory tested, only striploins from early-castrated animals were rated as being of higher eating\ud quality than striploins from late-castrate, short-scrotum or entire animals. Sensory test of meat quality as measured by MQ4 did not differ between carcasses of non-castrated animals that were graded as either "steer" or "bull" (43.862 ± 0.990 vs 45.078 ± 1.807, respectively; mean ± SEM), indicating that taste panels did not detect differences in the eating quality of the three muscles from these animals. This suggests that grading of carcasses of young animals on secondary sex characteristics may not accurately reflect the eating quality of meat from those carcasses. There were also significant disparities in the allocation of MSA star grades based on either MSA grading outcomes or taste panel sensory test results. Production of young entire 80S indicus males offers the potential for significant returns for northern beef producers with little impact to meat quality. However, there is a need for further data to be generated to allow the MSA grading model to be further refined for 80S indicus cattle

Bos indicus cattle possess greater basal concentrations of HSP27, alpha B-crystallin, and HSP70 in skeletal muscle in vivo compared with Bos taurus cattle

The objectives of the present study were to evaluate the basal concentrations of heat shock proteins (HSP) between Bos indicus and Bos taurus cattle and determine if HSP basal concentrations change as an animal matures. A total of 40 cattle were used in a 2 × 2 factorial design to evaluate the effects of genotype and age (heifers and mature cows) on basal concentrations of Heat Shock Protein 27 (HSP27), alpha B-crystallin (Cryab), and Heat Shock Protein 70 (HSP70). Each experimental group of 10 animals was sampled on a separate day over a period of 4 weeks during July 2014. A muscle sample was collected from the longissimus thoracis (LT) and concentrations of HSP were quantified using ELISA. There were no significant differences in HSP concentration for the interaction between age and genotype or for age alone. Bos indicus cattle had greater (P < 0.05) basal concentrations of HSP27, Cryab, and HSP70 in the LT than Bos taurus cattle. The results of this study show that basal in vivo HSP concentrations differ between Bos indicus and Bos taurus cattle. However, further studies are needed to investigate the relationship between HSP concentrations and meat tenderness with respect to genotypes to see if HSP concentrations account for at least some variability in tenderness differences

Treating Bos indicus bulls with rumen transfaunation after 24 hours of transportation does not replete muscle glycogen

Twelve Bos indicus bulls were allocated to one of two treatment groups: rumen transfaunation (n = 6) given 10 kg of rumen fluid after transport or Control (n = 6), given 10 kg of deionised water after transport. Glycogen concentrations of the M. semimembranosus, M. semitendinosis and M. longisimus dorsi were measured before transport on Day –7 and after transport on Day 0, Day 1, Day 4 and Day 9. Feed intake, liveweight gain, plasma metabolites and electrolytes were recorded on the sampling days. Rumen transfaunation increased the dry matter intake of treated bulls compared with the bulls treated with deionised water. Rumen transfaunation had no effect on glycogen concentrations of the M. semimembranosus, M. semitendinosis and M. longisimus dorsi compared with the bulls treated with deionised water. The M. semimembranosus and the M. semitendinosis decreased in glycogen concentration immediately after transport on Day 0 but repleted to pre-transportation concentrations within 1 day. However, the M. longisimus dorsi demonstrated no change in glycogen concentration between the pre-transportation sample on Day –7 and Day 0 or Day 1 after transportation. The M. longisimus dorsi of the bulls increased in glycogen concentration between Day 1 and Day 4 after transportation. The bulls in this experiment demonstrated that muscle glycogen, as measured at the M. longissimus dorsi, cannot recover to sufficient concentrations (40–45 µmol of glycogen concentration per gram muscle) to ensure normal meat quality until between 1 and 4 days of rest when feeding Rhodes grass hay ad libitum

Prepartum dietary energy source fed to beef cows: II. Effects on progeny postnatal growth, glucose tolerance, and carcass composition

Mature Angus-cross beef cows (n = 228) were used to evaluate effects of prepartum dietary energy source on postnatal growth and carcass composition of progeny in a 2-yr study. Starting at approximately 160 d of gestation, cows were fed diets consisting of 1 of 3 primary energy sources: grass hay (HY), corn (CN), or dried corn distillers grains with solubles (DG). The CN and DG diets were limit-fed to achieve similar energy intakes as cows fed HY. Following parturition, cows were fed a common diet and managed as a single group. Calves were weaned at an average of 185 ± 6 d of age and backgrounded for 28 d. A subset of progeny (n = 134) was individually fed a common finishing diet until slaughter, when each calf reached 1.2 ± 0.05 cm of backfat. A glucose tolerance test (GTT) was conducted in year 2 on 4 calves/treatment after 41 and 111 d on the finishing diet (DOF). Calf birth weights were greater (P = 0.002) in calves from cows fed CN and DG than calves from cows fed HY, and weaning BW (P = 0.08) was less for calves from cows fed HY vs. CN. Receiving BW, final BW, and HCW did not differ (P ≥ 0.16) among treatments. No difference (P ≥ 0.28) in ADG, morbidity, and mortality from birth to slaughter was observed among treatments. In response to a GTT, increased DOF resulted in greater (P ≤ 0.005) fasting insulin, faster glucose disappearance rate, and greater insulin:glucose area under the curve ratio. Glucose disappearance rate was greater (P = 0.01) in calves from cows fed CN than in calves from cows fed HY or DG. A greater initial insulin response (P = 0.005) was observed in calves from cows fed CN or DG than in calves from cows fed HY. Carcass traits used to measure yield grade did not differ (P ≥ 0.19) among treatments. Calves from dams fed CN had the lowest marbling score (P = 0.03) and intramuscular fat content (P = 0.07). These results indicate that prepartum maternal dietary energy source can alter fetal adipose tissue development and insulin sensitivity resulting in long-term effects on progeny's intramuscular fat deposition. Moreover, present findings suggest that increasing the number of days on a corn-based finishing diet increases insulin resistance in beef cattle.Fil: Radunz, A. E.. Ohio State University; Estados UnidosFil: Fluharty, F. L.. Ohio State University; Estados UnidosFil: Relling, Alejandro Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria "Ing. Fernando Noel Dulout". Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Genética Veterinaria; ArgentinaFil: Felix, T. L.. University of Illinois. Urbana - Champaign; Estados UnidosFil: Shoup, L. M.. University of Illinois. Urbana - Champaign; Estados UnidosFil: Zerby, H.N.. Ohio State University; Estados UnidosFil: Loerch, S.C.. Ohio State University; Estados Unido