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Made available in DSpace on 2018-11-28T04:46:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-01-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) This experiment evaluated the effects of temperament on physiological, productive, and reproductive responses in Bos indicus beef cows. A total of 953 lactating, multiparous, non-pregnant Nelore cows (age = 99 +/- 2 mo; days post-partum = 51.4 +/- 0.3 d; BCS = 5.34 +/- 0.04; BW = 430 +/- 2 kg) were allocated into 8 groups of approximately 120 cows each. Groups were assigned to an estrus synchronization + timed-AI protocol at the beginning of the breeding season. Concurrently with AI, blood samples were collected, hair samples were clipped from the tail switch, and cow temperament was evaluated via chute score and exit velocity. Individual exit score was calculated within each group by dividing exit velocity into quintiles and assigning cows with a score from 1 to 5 (1 = slowest; 5 = fastest cow). Temperament scores were calculated by averaging cow chute score and exit score, and used to define cow temperament ( 3 = excitable, n = 227; EXC). Cows not pregnant to AI were assigned to a second timed-AI protocol (n = 184 ADQ and 72 EXC) or exposed (n = 269 ADQ and 90 EXC) to bulls for 60 d. Pregnancy status was verified 30 d after each AI and 45 d after the breeding season via transrectal ultrasound. Cow age, BW, BCS, and d post-partum at the beginning of the breeding season were similar (P >= 0.27) between ADQ and EXC cows. At first timed-AI, EXC had greater (P < 0.01) serum cortisol but similar (P >= 0.87) serum haptoglobin and hair cortisol concentrations compared with ADQ cows (49.1 vs. 39.1 ng/mL of serum cortisol, SEM = 1.0). Pregnancy rate to first timed-AI tended (P = 0.09) to be less in EXC vs. ADQ cows (41.0 vs. 47.3%; SEM = 3.6), whereas no treatment differences were detected (P >= 0.23) for subsequent pregnancy outcomes. Calving rate was less (P = 0.04) in EXC vs. ADQ cows (68.3 vs. 74.8%; SEM = 2.2), which can be attributed to the greater (P = 0.05) pregnancy loss detected in EXC cows (9.9 vs. 5.9%; SEM = 1.4). Weaning rate tended (P = 0.09) to be less, whereas calf weaning BW and age were less (P = 0.05) in EXC vs. ADQ cows (63.9 vs. 69.4%, SEM = 2.4; 209 vs. 212 d, SEM = 1; 204 vs. 210 kg, SEM = 2). Hence, kg of calf weaned/cow exposed to breeding was reduced (P = 0.04) in EXC vs. ADQ cows (130 vs. 146 kg, SEM = 5). In summary, B. indicus cows with excitable temperament had reduced reproductive performance and overall productivity compared to cohorts with adequate temperament when exposed to timed-AI + natural breeding. Oregon State Univ, Eastern Oregon Agr Res Ctr, Burns, OR 97720 USA Univ Estadual Paulista, Fac Med Vet & Zootecnia, BR-18618970 Botucatu, SP, Brazil Unisalesiano Auxilium, BR-16016500 Aracatuba, SP, Brazil Univ Sao Paulo, ESALQ, Dept Zootecnia, BR-13418900 Piracicaba, SP, Brazil UNESP Univ Estadual Paulista, Fac Med Vet & Zootecnia, Programa Posgrad Zootecnia, BR-18618970 Botucatu, SP, Brazil Univ Estadual Paulista, Fac Med Vet & Zootecnia, BR-18618970 Botucatu, SP, Brazil UNESP Univ Estadual Paulista, Fac Med Vet & Zootecnia, Programa Posgrad Zootecnia, BR-18618970 Botucatu, SP, Brazil FAPESP: 2014/14136-4 FAPESP: 2014/19485-7

Made available in DSpace on 2018-11-26T15:37:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-09-01 Made available in DSpace on 2018-12-11T16:44:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-09-01 Item merged in doublecheck by Luana Priscila Costa (luana@reitoria.unesp.br) on 2019-02-15T18:16:28Z Item was identical to item(s): 171292, 161437 at handle(s): http://hdl.handle.net/11449/169013, http://hdl.handle.net/11449/159219 USDA-NIFA Oregon Ninety Angus × Hereford calves were ranked by sex, BW, and age and assigned to 1 of 3 vaccination schemes against the bovine respiratory disease complex: 1) vaccination at weaning (d 0) and a booster at feedlot entry (d 30; CON; n = 30), 2) vaccination 15 d before weaning (d −15) and a booster 15 d before feedlot entry (d 15; EARLY; n = 30), and 3) vaccination 15 d after weaning (d 15) and a booster 15 d after feedlot entry (d 45; DELAYED; n = 30). From d −15 to 7, calves were maintained as a single group on pasture. On d 8, calves were placed into 1 of 18 drylot pens (6 pens/treatment; 5 calves/pen) and fed alfalfa–triticale hay. On d 29, calves were transported 1,440 km in a livestock trailer and unloaded on d 30 at the same feed yard with the same pen arrangement used prior to transport. From d 30 to 75, calves were fed a receiving diet based on alfalfa–triticale hay + corn-based concentrate. Calf BW was recorded on 2 consecutive days (d −15, −14, 0, 1, 28, 29, 75, and 76). Blood samples were collected on d −15, 0, 15, 30, 45, 60, and 75. The EARLY calves had less (P ≤ 0.09) ADG before weaning (d −15 to −1); however, they had greater (P ≤ 0.01) ADG during feedlot receiving (d 30 to 75) compared with calves with the other treatments. During preconditioning (d 0 to 29), CON calves had greater (P ≤ 0.04) DMI compared with EARLY and DELAYED calves. During feedlot receiving, no treatment differences were detected (P ≥ 0.17) for hay or concentrate DMI, G:F, and morbidity and mortality rates. There were no treatment effects on calf BW at weaning and at the end of the preconditioning or receiving periods (P ≥ 0.65). Plasma concentrations of antibodies against Mannheimia haemolytica were greater (P ≤ 0.05) in EARLY calves than in CON and DELAYED calves on d 0, greater (P ≤ 0.04) for CON calves than for EARLY and DELAYED calves on d 15, greater (P ≤ 0.02) in DELAYED and EARLY calves than in CON calves on d 30, and greater (P = 0.03) in EARLY calves than in CON calves on d 75. Plasma concentrations of antibodies against bovine viral diarrhea viruses were greater (P ≤ 0.04) in EARLY calves than in CON and DELAYED calves on d 15 and greater for EARLY and CON calves than for DELAYED calves on d 30 and 45. Collectively, EARLY calves had greater plasma concentrations of antibodies against the evaluated pathogens at feedlot entry and increased ADG during receiving compared with their CON and DELAYED cohorts. Hence, anticipating initial and booster vaccinations against respiratory pathogens to provide both doses prior to feedlot entry appears to be a valid strategy to enhance cattle health and performance during feedlot receiving. Oregon State University Eastern Oregon Agricultural Research Center UNESP Faculdade de Medicina Veterinária e Zootecnia Faculdade de Medicina Veterinária e Zootecnia UNESP - Univ. Estadual Paulista UNESP Faculdade de Medicina Veterinária e Zootecnia Faculdade de Medicina Veterinária e Zootecnia UNESP - Univ. Estadual Paulista USDA-NIFA Oregon: ORE00142