Alice P Brandão

Effects of organic complexed or inorganic Co, Cu, Mn and Zn supplementation during a 45-day preconditioning period on productive and health responses of feeder cattle

This experiment evaluated production and health parameters among cattle offered concentrates containing inorganic or organic complexed sources of supplemental Cu, Co, Mn and Zn during a 45-day preconditioning period. In total, 90 Angus×Hereford calves were weaned at 7 months (day -1), sorted by sex, weaning BW and age (261±2 kg; 224±2 days), and allocated to 18 drylot pens (one heifer and four steers per pen) on day 0; thus, all pens had equivalent initial BW and age. Pens were randomly assigned to receive a corn-based preconditioning concentrate containing: (1) Cu, Co, Mn and Zn sulfate sources (INR), (2) Cu, Mn, Co and Zn complexed organic source (AAC) or (3) no Cu, Co, Mn and Zn supplementation (CON). From day 0 to 45, cattle received concentrate treatments (2.7 kg/animal daily, as-fed basis) and had free-choice access to orchardgrass (Dactylis glomerata L.), long-stem hay and water. The INR and AAC treatments were formulated to provide the same daily amount of Co, Cu, Mn and Zn at a 50-, 16-, 8- and ninefold increase, respectively, compared with the CON treatment. On day 46, cattle were transported to a commercial feedlot, maintained as a single pen, and offered a free-choice receiving diet until day 103. Calf full BW was recorded on days -1 and 0, 45 and 46, and 102 and 103 for average daily gain (ADG) calculation. Liver biopsy was performed on days 0 (used as covariate), 22 and 45. Cattle were vaccinated against respiratory pathogens on days 15, 29 and 46. Blood samples were collected on days 15, 29, 45, 47, 49, 53 and 60. During preconditioning, mean liver concentrations of Co, Zn and Cu were greater (P⩽0.03) in AAC and INR compared with CON. No treatment effects were detected (P⩾0.17) for preconditioning feed intake, ADG or feed efficiency. No treatment effects were detected (P⩾0.48) for plasma concentrations of antibodies against Mannheimia haemolytica, bovine viral diarrhea types 1 and 2 viruses. Plasma haptoglobin concentrations were similar among treatments (P=0.98). Mean plasma cortisol concentration was greater (P⩽0.04) in CON compared with INR and AAC. No treatment effects were detected (P⩾0.37) for cattle ADG during feedlot receiving. Hence, INR and AAC increased liver concentrations of Co, Zn and Cu through preconditioning, but did not impact cattle performance and immunity responses during preconditioning and feedlot receiving.

Supplementing calcium salts of soybean oil after artificial insemination increases pregnancy success in Bos taurus beef cows1

© The Author(s) 2018. Published by Oxford University Press on behalf of the American Society of Animal Science. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact journals.permissions@oup.com. Transl. Anim. Sci. 2018.2:S9–S13 doi: 10.1093/tas/txy017

Supplementing Micro-Aid to optimize health and performance of receiving cattle

© The Author(s) 2018. Published by Oxford University Press on behalf of the American Society of Animal Science. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact journals.permissions@oup.com. Transl. Anim. Sci. 2018.2:S22–S26 doi: 10.1093/tas/txy018

Supplementing Ca salts of soybean oil after artificial insemination increases pregnancy success in Bos taurus beef cows1

Two experiments investigated the effects of supplementing Ca salts of soybean oil (CSSO) during early gestation on reproductive function and pregnancy rates to AI in Bos taurus beef cows. In Exp. 1, 771 suckled, lactating, multiparous Angus cows were divided into 22 groups of approximately 35 cows per group and timed inseminated on day 0. After AI, groups were assigned randomly to receive (as-fed basis) 100 g of ground corn + 100 g of soybean meal per cow/d, in addition to 1) 100 g/cow daily of CSSO (n = 11) or 2) 87 g of prilled saturated fat + 13 g of limestone per cow/d (CON; n = 11). Groups were maintained in individual tall fescue-dominated pastures and offered treatments from day 0 to 21. Pregnancy status was determined between days 45 and 55 via transrectal ultrasonography. Cows receiving CSSO had greater (P = 0.01) pregnancy rates to timed AI compared with CON (60.2 vs. 51.7%; SEM = 4.2). In Exp. 2, 90 suckled, lactating, multiparous Angus × Hereford cows housed in 18 drylot pens (5 cows per pen) were assigned to the same timed AI program and treatments from Exp. 1 (9 pens per treatment) and received 20 kg/d (DM basis) of grass-alfalfa hay. Transrectal ultrasonography was performed to verify ovulation and corpus luteum (CL) volume before AI (day 0), on days 7 and 15. After ultrasonography on day 15, cows diagnosed without a CL on day 0, but with a CL greater than 0.38 cm3 in volume on days 7 and 15 (2 or 3 cows per pen; CSSO, n = 20; CON, n = 24), were assigned to conceptus collection via transcervical flushing and endometrial biopsy in the uterine horn ipsilateral to the CL. Blood samples were collected for FA analysis on days 0, 7, and 15. Blood was collected from cows not assigned to conceptus collection for whole-blood RNA extraction on day 20 and for pregnancy diagnosis on day 30 by measuring concentrations of pregnancy-associated glycoproteins. Cows receiving CSSO had greater (P ≤ 0.04) mean plasma concentrations of linoleic acid and ω-6 FA compared with CON on days 7 and 15. Moreover, CSSO supplementation increased (P = 0.05) mRNA expression of interferon-tau by the conceptus and blood mRNA expression of interferon-stimulated gene 15 and 20,50-oligoadenylate synthetase on day 20 in gestating cows. Hence, post-AI CSSO supplementation to B. taurus beef cows improved pregnancy rates to timed AI, which can be associated with increased mRNA expression of interferon-tau by the conceptus when CSSO is supplemented during early gestation.

Productive and physiological responses of feeder cattle supplemented with Yucca schidigera extract during feedlot receiving

This experiment evaluated the effects of supplementing a saponin-containing feed ingredient, manufactured from purified extract of Yucca schidigera [Micro-Aid (MA); DPI Global; Porterville, CA], on performance, health, and physiological responses of receiving cattle. A total of 105 recently weaned Angus x Hereford calves (75 steers and 30 heifers), originating from eight cow-calf operations, were obtained from an auction facility on day -2 and road transported (800 km; 12 h) to the experimental facility. Immediately after arrival on day -1, shrunk BW was recorded and calves were grouped with free-choice access to grass hay, mineral supplement, and water. On day 0, calves were ranked by sex, source, and shrunk BW, and allocated to one of 21 pens (5 calves/pen; being one or two heifers within each pen). Pens were assigned to receive a total mixed ration (TMR) and one of three treatments (as-fed basis): (1) 1 g/calf daily of MA (M1; n = 7), (2) 2 g/calf daily of MA (M2; n = 7), or (3) no MA supplementation (CON; n = 7). Calves received the TMR to yield 15% (as-fed basis) orts, and treatments were top-dressed from days 0 to 59. Calves were assessed for bovine respiratory disease (BRD) signs and TMR intake was recorded for each pen daily. Calves were vaccinated against BRD pathogens on days 0 and 21. Final shrunk BW was recorded on day 60, and blood samples were collected on days 0, 2, 6, 10, 14, 21, 28, 34, 45, and 59. ADG was greater (P = 0.03) in M2 vs. M1 and CON (1.53, 1.42, and 1.42 kg/day, respectively), and similar (P = 0.95) between M1 and CON calves. No treatment effects were detected for TMR intake (P = 0.52), whereas feed efficiency was greater (P ≤ 0.05) in M2 vs. M1 and CON calves (213, 200, and 204 g/kg, respectively) and similar (P = 0.40) between M1 and CON calves. No treatment effects were detected (P = 0.39) for diagnosis of BRD signs. The number of antimicrobial treatments required upon BRD diagnosis was greater (P ≤ 0.01) in CON vs. M1 and M2 (1.40, 1.05, and 1.10 treatments, respectively), and similar (P = 0.60) between M1 and M2 calves. No other treatment effects were detected (P ≥ 0.23), including circulating concentrations of hormones and metabolites, serum antibody titers to BRD pathogens, and mRNA expression of innate immunity genes in whole blood. Collectively, results from this experiment suggest that MA supplementation at 2 g/animal daily enhances performance and response to BRD treatment in high-risk cattle during feedlot receiving.