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The objective of this study was to determine the effects of alternative-measurements of body weight and DMI used to evaluate residual feed intake (RFI). Weaning weight (WW), ADG, and DMI were recorded on 970 growing purebred Charolais bulls (n = 519) and heifers (n = 451) and 153 Red Angus growing steers (n = 69) and heifers (n = 84) using a GrowSafe (GrowSafe, Airdrie, Alberta, Canada) system. Averages of individual DMI were calculated in 10-d increments and compared to the overall DMI to identify the magnitude of the errors associated with measuring DMI. These incremental measurements were also used in calculation of RFI, computed from the linear regression of DMI on ADG and midtest body weight0.75 (MMWT). RFI_Regress was calculated using ADG_Regress (ADG calculated as the response of BW gain and DOF) and MMWT_PWG (metabolic midweight calculated throughout the postweaning gain test), considered the control in Red Angus. A similar calculation served as control for Charolais; RFI was calculated using 2-d consecutive start and finish weights (RFI_Calc). The RFI weaning weight (RFI_WW) was calculated using ADG_WW (ADG from weaning till the final out weight of the postweaning gain test) and MMWT_WW, calculated similarly. Overall average estimated DMI was highly correlated to the measurements derived over shorter periods, with 10 d being the least correlated and 60 d being the most correlated. The ADG_Calc (calculated using 2-d consecutive start and finish weight/DOF) and ADG_WW were highly correlated in Charolais. The ADG_Regress and ADG_Calc were highly correlated, and ADG_Regress and ADG_WW were moderately correlated in Red Angus. The control measures of RFI were highly correlated with the RFI_WW in Charolais and Red Angus. The outcomes of including abbreviated period DMI in the model with the weaning weight gain measurements showed that the model using 10 d of intake (RFI WW_10) was the least correlated with the control measures. The model with 60 d of intake had the largest correlation with the control measures. The fewest measured intake days coupled with the weaning weight values providing acceptable predictive value was RFI_WW_40, being highly correlated with the control measures. As established in the literature, at least 70 d is required to accurately measure ADG. However, we conclude that a shorter period, possibly as few as 40 d is needed to accurately estimate DMI for a reliable calculation of RFI.

The objective of this experiment was to determine the effect of reducing the duration of controlled internal drug-release insert (CIDR) exposure in a CIDR-based, fixed-time-AI protocol on pregnancy per AI (P/AI) and pregnancy rates in beef heifers. The experiment was conducted in 4 consecutive years. British crossbred heifers (yr 1, n = 82; yr 2, n = 68; yr 3, n = 86; yr 4, n = 53) were stratified by BW and age and were assigned randomly to 1 of 2 treatments: (1) CIDR7 heifers (n = 145) received a CIDR insert for 7 d; and (2) CIDR5 heifers (n = 144) received a CIDR insert for 5 d. Heifers in CIDR7 and CIDR5 were given prostaglandin F2α (25 mg) upon CIDR removal followed by gonadotropin-releasing hormone (75 μg) and fixed-time AI 56 to 59 h after CIDR removal. Estrual behavior was monitored following CIDR removal. In all 4 yr, heifers received AI by a single inseminator. Fourteen days after AI, heifers were exposed to bulls for 40 d. Blood samples were collected on the day of CIDR insertion. Pregnancy status was determined by ultrasonography at d 35 and d 67 to 82 after AI. Data were analyzed by logistic regression and ANOVA. Percentage of heifers detected in estrus was different (P 0.2) between treatments. At CIDR insertion, mean serum progesterone concentrations were similar between CIDR7 and CIDR5, and there was no effect of treatment-by-year interaction on progesterone concentrations (P > 0.2). There was a treatmentby-year interaction effect on P/AI (P < 0.05). For CIDR7 and CIDR5, in yr 1, P/AI was 39 and 65.8% (P < 0.05), respectively; in yr 2, P/AI was 64.7and 41.1% (P < 0.05), in yr 3, P/AI was 59 and 73.8% (P = 0.09), and in yr 4, P/AI was 50 and 70.4% (P = 0.25). Overall, P/AI tended (P = 0.07) to be greater for CIDR5 compared with CIDR7 (63.8 vs. 53%). Regardless of treatment, heifers detected in estrus had a greater (P < 0.01) P/AI compared with those not detected in estrus (65.9 vs 47.9%). The final pregnancy rates of heifers were unaffected by the treatment protocols or year (92 and 95.5% for CIDR7 and CIDR5, respectively). The P/AI results from this study suggest that reducing the duration of CIDR treatment from 7 to 5 d in a CIDR-based and single-prostaglandin-injection, fixed-time-AI protocol may improve P/AI in beef heifers.

Significant amounts of sex-selected or sexed semen only became commercially available to the beef industry in 2008. The use of sexed semen in the beef industry may be limited by information on results in various applications as well as reduced reproductive efficiency. Use of sexed semen in AI applications in beef cattle results in a 10 to 20% decrease in AI pregnancy rates. This decrease is consistent with observations in dairy cattle inseminated with sexed semen. However, 89 to 94% of females pregnant to sexed semen produce calves of the desired sex. Pregnancy rates to sexed semen are not different among beef heifers and postpartum beef cows. The percentage of transferable embryos from embryo-transfer or in vitro–fertilization procedures is reduced when sexed semen is used in place of conventional semen. Despite the reduction in overall pregnancies or embryos from the use of sexed semen, the economic and genetic advantage of producing more offspring of a desired sex may offset the reduction in total calves produced. Feasible applications for sexed semen in beef cattle include generation of crossbred maternal-line females, reducing generation interval by heifers producing only heifers, and shifting of sex ratios to enhance marketing. In addition, the application of sexed semen in in vitro–fertilization systems appears to be extremely promising.

Idaho beef producers and animal health product retailers participated in a study to gather data on the handling and management of animal health products. Data loggers were placed in 176 refrigerators (129 producers’ and 47 retailers’) recording temperatures in 10-min intervals for a minimum of 48 h. The approximate age, type, and location of the producers’ refrigerators were recorded, along with where the products were stored in the refrigerator. An inventory of each producers’ refrigerator was taken, with expired and opened products recorded. Almost one-third (31%) of the producers’ refrigerators maintained the recommended temperature range of 2 to 7°C > 95% of the time, and one-third (33.3%) of the producers’ refrigerators maintained the recommended temperature range 95% of the time, and 17.0% were in the range

A survey was conducted to quantify incidence of Beef Quality Assurance (BQA)-related defects in market beef and dairy cows and bulls selling at auction during 2 seasons in 2008. Twenty-three BQA-related traits were evaluated by 9 trained personnel during sales at 10 livestock auction markets in Idaho (n = 5; beef and dairy), California, (n = 4; dairy only), and Utah (n = 1; beef and dairy). Overall, 18,949 unique lots (8,213 beef cows, 1,036 beef bulls, 9,177 dairy cows, and 523 dairy bulls,) consisting of 23,479 animals (9,299 beef cows, 1,091 beef bulls, 12,429 dairy cows, and 660 dairy bulls) were evaluated during 125 sales (64 spring, 61 fall) for dairy and 79 sales (40 spring, 39 fall) for beef. The majority of market beef cows and bulls (60.9 and 71.3%, respectively) were predominantly black-hided, and the Holstein hide pattern was observed in 95.4 and 93.6% of market dairy cows and bulls, respectively. Market cattle weighed 548 ± 103.6 kg (beef cows), 751 ± 176.1 kg (beef bulls), 658 ± 129.7 kg (dairy cows), and 731 ± 150.8 kg (dairy bulls). Most beef cows (79.6%) weighed 455 to 726 kg, and most beef bulls (73.8%) weighed 545 to 954 kg, respectively. Among market beef cattle, 16.0% of cows and 14.5% of bulls weighed less than 455 and 545 kg, respectively, and 63.7% of dairy cows and 81.5% of dairy bulls weighed 545 to 817 kg or 545 to 954 kg, respectively. However, 19.5% of dairy cows and 13.1% of dairy bulls weighed less than 545 kg. Mean BCS for beef cattle (9-point scale) was 4.7 ± 1.2 (cows) and 5.3 ± 0.9 (bulls), and for dairy cattle (5-point scale) was 2.6 ± 0.8 (cows) and 2.9 ± 0.6 (bulls). Some 16.5% of beef cows and 4.1% of beef bulls had a BCS of 1 to 3, whereas 34.8% of dairy cows and 10.4% of dairy bulls had a BCS of 2 or less. Emaciation (beef BCS = 1, dairy BCS = 1.0) or near-emaciation (beef BCS = 2, dairy BCS = 1.5) was observed in 13.3% of dairy cows and 3.9% of beef cows. Among beef cattle, 15.1% of cows and 15.4% of bulls were considered lame. In contrast, 44.7% of dairy cows and 26.1% of dairy bulls were lame. Ocular neoplasia (cancer eye) was observed in only 0.6% of beef cows, 0.3% of beef bulls, 0.3% of dairy cows, and 0.0% of dairy bulls. However, among animals with ocular neoplasia, it was cancerous in 34.4% of beef bulls, 48.0% of dairy cows, and 73.3% of beef cows. In conclusion, numerous quality defects are present in market beef and dairy cattle selling at auction in the Western United States, which could influence their value at auction.

A study was conducted to determine the effect of inclusion of estradiol cypionate (ECP) in a conventional gonadotropin-releasing hormone (GnRH)-prostaglandin F2α (PGF2α)-GnRH-timed AI protocol (Cosynch) on conception and pregnancy rates in beef cattle. The objective was to determine if administration of 0.25 mg of ECP at the time of the second GnRH injection would effectively increase conception to AI and improve pregnancy rates. Cows were presynchronized with an i.m. injection of 25 mg of PGF2αon d 14. On d 0, Cosynch (COS) was initiated with administration of 100 μg GnRH (i.m.) followed 7 d later with 25 mg of PGF2α (i.m.). On d 9 cows were paired by age, BCS, and BW and assigned randomly to receive either GnRH (100 g) + 0.25 mg ECP (COSECP; n = 90) or GnRH (100 μg) + vehicle (COS-C; n = 93). Following treatment, all cows were immediately inseminated by a single inseminator. Pregnancy status was determined by ultrasonography 35 and 70 d postinsemination. Data were analyzed by logistic regression. Pregnancy per AI (53.3% COS-ECP vs. 57.0% COS-C) and 70-d pregnancy rates to AI and natural service (92.2% COS-ECP vs. 90.3% COS-C) did not differ between treatments. Days postpartum had no effect on the odds ratio of pregnancy. The results indicate that the incorporation of 0.25 mg of ECP into the Cosynch protocol did not affect pregnancy per AI and 70-d pregnancy rates in beef cattle.

Relationships between residual feed intake (RFI) and other performance variables were determined using 54 purebred Angus steers. Individual feed intake and BW gain were recorded during a 70-d post-weaning period to calculate RFI. After the 70-d post-weaning test, steers were fed a finishing ration to a similar fat thickness (FT), transported to a commercial facility, and slaughtered. A subsample of carcasses (n = 32) was selected to examine the relationships among RFI, meat quality, and palatability. Steers were categorized into high (> 0.5 SD above the mean; n = 16), medium (mid; +/- 0.5 SD from the mean; n = 21), and low (< 0.5 SD below the mean; n = 17) RFI groups. No differences were detected in ADG, initial BW, and d 71 BW among the high, mid, and low RFI steers. Steers from the high RFI group had a greater DMI (P = 0.004) and feed conversion ratio (FCR; DMI:ADG; P = 0.002) compared with the low RFI steers. Residual feed intake was positively correlated with DMI (r = 0.54; P = 0.003) and FCR (r = 0.42; P = 0.002), but not with initial BW, d 71 BW, d 71 ultrasound FT, initial ultrasound LM area, d 71 ultrasound LM area, or ADG. The FCR was positively correlated with initial BW (r = 0.46; P = 0.0005), d 71 BW (r = 0.34; P = 0.01), and DMI (r = 0.40; P = 0.003) and was negatively correlated with ADG (r = -0.65; P = 0.001). There were no differences among RFI groups for HCW, LM area, FT, KPH, USDA yield grade, marbling score, or quality grade. Reflectance color b* scores of steaks from high RFI steers were greater (P = 0.02) than those from low RFI steers. There was no difference between high and low RFI groups for LM calpastatin activity. Warner-Bratzler shear force and sensory panel tenderness and flavor scores of steaks were similar across RFI groups. Steaks from high RFI steers had lower (P = 0.04) off-flavor scores than those from low RFI steers. Cook loss percentages were greater (P = 0.005) for steaks from low RFI steers than for those from mid RFI steers. These data support current views that RFI is independent of ADG, but is correlated with DMI and FCR. Importantly, the data also support the hypothesis that there is no relationship between RFI and beef quality in purebred Angus steers.

In 2004 a mail-in survey was conducted to establish a baseline level of awareness and knowledge related to dairy beef quality assurance (BQA) issues in Idaho. A 30-question survey was mailed to every (n = 736) registered Idaho dairy. Two-hundred seventy-three (37%) dairies participated and were categorized as small (n201 cows; 53.5%), medium-sized (n = 201 to 1,000 cows; 27.1%) or large (n1,000 cows; 19.4%). The majority of respondents were dairy owners (83%). Eighty-nine percent of respondents indicated they followed BQA recommendations for animal care. The neck region in cows was used by 68% of respondents for i.m. injections and by 80% for s.c. injections. In calves, the values were 61 and 78%, respectively. Seventy-four percent of respondents indicated they had been trained for injections. Training methods cited included veterinarians (19.8%), dairy owners (16.8%), experience (9.9%), and BQA events or schools (4.5%). The importance of BQA in the dairy industry was rated 2.6 on a 5-point scale (0 = low; 4 = high). Participants rated the effect of dairy animals on the beef industry at 2.5. Plastic ear tags were the preferred method of animal identification, with 100% of large dairies, 97.3% of medium-sized dairies, and 84% of small dairies citing their use. Less than 10% used electronic identification for their animals. Almost half (48%) of large and medium-sized (49%) dairies and 32% of small dairies supported a national animal identification program. A mandatory identification program was supported by 41, 69, and 59% for small, medium-sized, and large dairies, respectively. The percentage of dairies keeping records was similar between small (93%), medium-sized (99%), and large (100%) dairies. Most small dairies (58%) used some form of paper records, whereas most medium-sized (85%) and large (100%) dairies used computers for record keeping. The preferred method to market cull cows by Idaho dairies was the auction market (64%), followed by order buyers (17%), direct to the packer (17%), private treaty sales (16%), and forward contracts (1%). To market calves, dairies used private treaty sales (52%), auction markets (42%), order buyers (14%), and forward contracts (1%). The results of this study will be used by University of Idaho Extension faculty in the design, development, and delivery of dairy BQA program information and materials.

The rat-tail condition had no effect on birth weight, weaning weight, or gain from birth to weaning. However, the rat-tail calves had significantly lower rates of gain from weaning to yearling (during the winter months) than the normal calves, resulting in 43 lb lighter yearling weights. The gains of steers from yearling to slaughter were not significantly different, but the rat-tail steers were 78 lb lighter (P=.01) and 13 days older (P=.15) at slaughter than the normal steers.

Data on 1210 spring-born (1983 to 1988) yearling heifers were analyzed by paternal half-sib procedures to obtain genetic and phenotypic parameter estimates involving birth weight and pelvic measurements. Data included records on 629 Angus, 325 Simmental, and 256 Salers representing 93, 49, and 22 paternal half-sib sire groups, respectively. Heritabilities for birth weight (BW), pelvic height (PH), pelvic width (PW), and pelvic area (PA) for Angus were 0.30, 0.61, 0.28, and 0.43, respectively. Corresponding values for Simmental and Salers heifers were 0.14, 0.34, 0.44, 0.37, and 0.18, 0.02, 0.29, 0.15, respectively. Genetic correlations among pelvic measurements (PH-PW, PH-PA, PW-PA) were positive (0.25 to 1.03) except for the estimate of −0.07 for PH-PW in Simmentals. Genetic correlations between BW and the 3 pelvic measurements (BW-PH, BW-PW, BW-PA) were negative (−0.18 to −0.36) except for the estimates of 0.53 (BW-PW) and 0.26 (BW-PA) in Simmentals and 2.84 (BW-PH) and 0.39 (BW-PA) in Salers. Phenotypic correlations among pelvic measurements ranged from 0.16 to 0.80. Phenotypic correlations between birth weight and the 3 pelvic measurements were consistently lower (−0.02 to 0.09) than the genetic correlations.