scholarly journals Treatments to Optimize the Use of Artificial Insemination and Reproductive Efficiency in Beef Cattle under Tropical Environments

2011 ◽  
Vol 2011 ◽  
pp. 1-10 ◽  
Author(s):  
Ocilon Gomes de Sá Filho ◽  
José Luiz Moraes Vasconcelos
Keyword(s):  
Body Weight ◽  
Beef Cattle ◽  
Artificial Insemination ◽  
Bos Taurus ◽  
Bos Indicus ◽  
Reproductive Efficiency ◽  
Tropical Environments ◽  
Final Maturation ◽  
Tropical Areas ◽  
Tropical Climates

Bos indicuscattle, the preferred genetic group in tropical climates, are characterized by having a lower reproductive efficiency thanBos taurus. The reasons for the poorer reproductive efficiency of theBos indicuscows include longer lengths of gestation and postpartum anestrus, a short length of estrous behavior with a high incidence of estrus occurring during the dark hours, and puberty at older age and at a higher percentage of body weight relative to mature body weight. Moreover, geography, environment, economics, and social traditions are factors contributing for a lower use of reproductive biotechnologies in tropical environments. Hormonal protocols have been developed to resolve some of the reproductive challenges of theBos indicuscattle and allow artificial insemination, which is the main strategy to hasten genetic improvement in commercial beef ranches. Most of these treatments use exogenous sources of progesterone associated with strategies to improve the final maturation of the dominant follicle, such as temporary weaning and exogenous gonadotropins. These treatments have caused large impacts on reproductive performance of beef cattle reared under tropical areas.

Cooled semen for fixed-time artificial insemination in beef cattle

2016 ◽  
Vol 28 (7) ◽  
pp. 1004 ◽  
Author(s):  
Juliana C. Borges-Silva ◽  
Márcio R. Silva ◽  
Daniel B. Marinho ◽  
Eriklis Nogueira ◽  
Deiler C. Sampaio ◽  
...  
Keyword(s):  
Beef Cattle ◽  
Sperm Motility ◽  
Artificial Insemination ◽  
Egg Yolk ◽  
Fixed Time ◽  
Pregnancy Rates ◽  
Reproductive Efficiency ◽  
Sperm Abnormalities ◽  
Hypoosmotic Swelling Test ◽  
Interesting Approach

This study evaluated the use of cooled semen in a fixed-time artificial insemination (FTAI) program compared with frozen–thawed semen to improve pregnancy rates in beef cattle. Ejaculates of three bulls were collected and divided into two treatments: (1) frozen–thawed semen and (2) cooled semen. Egg-yolk extender without glycerol was used for the cooled semen treatment. Straws (25 × 106 spermatozoa) were submitted to cooling for preservation at 5°C for 24 h, after which FTAI was performed. Nelore cows (n = 838) submitted to FTAI were randomly inseminated using frozen–thawed semen or cooled semen. There was a 20% increase in the pregnancy per AI (P AI–1) using cooled semen compared with frozen–thawed semen (59.9 ± 4.7 vs 49.4 ± 5.0%; P < 0.005). There was no difference in P AI–1 among the bulls (P = 0.40). The frozen–thawed semen had fewer functional spermatozoa than did the cooled semen when evaluated by sperm motility (61.7 vs 81.0%), slow thermoresistance test (41.7 vs 66.7%) and hypoosmotic swelling test (38.3 vs 53.7%; P < 0.05). The percentage of sperm abnormalities did not differ between the freeze–thawing and cooling processes (18.6 vs 22.1%; P > 0.05). Because there was less damage to spermatozoa and improvement in P AI–1, the use of cooled semen instead of frozen–thawed semen is an interesting approach to increase reproductive efficiency in cattle submitted to a FTAI protocol.

scholarly journals 41 Reproductive management of beef females in South America

2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 32-33
Author(s):  
Jose Luiz Moraes Vasconcelos ◽  
Reinaldo F Cooke ◽  
Mauro Meneghetti ◽  
Isaias Claro Junior ◽  
Rogerio Peres ◽  
...  
Keyword(s):  
South America ◽  
Bos Indicus ◽  
Reproductive Efficiency ◽  
Tropical Pastures ◽  
Beef Cow ◽  
Weaning Age ◽  
Beef Herds ◽  
Tropical Areas ◽  
Calving Season ◽  
Genetic And Environmental Factors

Abstract The majority of beef cow herds in South America are constituted by Bos indicus females, which have particular reproductive features that contribute to reduced reproductive efficiency compared with that of B. taurus cohorts. B. indicus heifers reach puberty at an older age compared with B. taurus heifers. Nutritional challenges are critical in cows maintained on low-quality tropical pastures, given that nutrient intake during the postpartum period is not sufficient to meet their requirements for growth and lactation. Several alternatives to enhance reproductive efficiency of B. indicus heifers and cows have been developed to address their inherent reproductive shortcomings. These research-based technologies include: a) hormonal protocols to induce puberty in nulliparous heifers, b) hormonal protocols to synchronize estrus and/or ovulation in B. indicus females to exploit their reproductive responses to artificial insemination, and c) genetic and environmental factors that influence reproductive success in beef herds, including reproductive diseases and excitable temperament of B. indicus females, which have been investigated to support/promote the development of appropriate mitigation technologies. The objective of this presentation is to discuss pharmacological and management technologies to improve reproductive performance of cow-calf systems from tropical areas in South America. Currently, there are hormonal treatments allowing South American B. indicus producers to reach the benchmark of 50% pregnancy rate to TAI, as well as enhance the percentage of cows becoming pregnant to AI at the beginning of the breeding season. This outcome is expected to optimize use of labor, and increase calf weaning age and weight via genetic improvement and concentration of births at the beginning of the calving season.

Bos indicus and Bos taurus crossbred dairy cattle in Australia. IV.* Progeny testing and expected rate of genetic improvement

1976 ◽  
Vol 27 (2) ◽  
pp. 309 ◽  
Author(s):  
IR Franklin ◽  
RH Hayman ◽  
RO Hewetson
Keyword(s):  
Dairy Cattle ◽  
Heat Tolerance ◽  
Genetic Improvement ◽  
Bos Taurus ◽  
Bos Indicus ◽  
Progeny Testing ◽  
Dairy Farmers ◽  
Improvement Program ◽  
Tropical Environments ◽  
Tick Resistance

A dairy improvement program designed to develop a breed of cattle adapted to tropical environments is described. Each year young crossbred (Bos indicus x Bos taurus) bulls are screened for heat tolerance and tick resistance, and then progeny-tested in the herds of cooperating dairy farmers. Estimates of phenotypic and genetic means, variances and correlations are presented for production of milk and milk components, and the rate of genetic improvement is discussed. In particular the heritability of milk yield in the crossbred progeny is 0.27, and the theoretical rate of improvement is 2.6% per year. ____________________ *Part III, Aust. J. Agric. Res., 25: 1023 (1974).

scholarly journals 21 Performance of growing beef cattle consuming bahiagrass hay treated with calcium oxide and molasses and supplemented with cottonseed meal

2019 ◽  
Vol 97 (Supplement_1) ◽  
pp. 19-19
Author(s):  
Francine M Ciriaco ◽  
Darren D Henry ◽  
Luara B Canal ◽  
Carla D Sanford ◽  
Gonzalo Barreneche ◽  
...  
Keyword(s):  
Beef Cattle ◽  
Cottonseed Meal ◽  
Calcium Oxide ◽  
Fixed Effects ◽  
Bos Taurus ◽  
Block Design ◽  
Bos Indicus ◽  
Paspalum Notatum ◽  
Experimental Unit ◽  
Feed Withdrawal

Abstract An experiment was conducted to evaluate the effects of bahiagrass (Paspalum notatum) hay treated with calcium oxide (CaO) and molasses, offered ad libitum, on performance of growing beef cattle supplemented with cottonseed meal. Sixty-four growing Bos taurus and Bos indicus influenced heifers (249 ± 26 kg of BW) and steers (249 ± 20 kg of BW) were used in a randomized complete block design. The experiment consisted of a 56 d period in which animals were weighed every 14 d. On d 0, animals were weighed after 16-h water and feed withdrawal, stratified by sex, breed, and BW, and blocked by initial BW. Cattle were then allotted to 16 dormant bahiagrass pastures (1.34 ha each; 4 animals/pasture), which were located in 2 different areas within 0.52 km of each other. Pastures were stratified by location and randomly assigned (n = 8 pastures/treatment) to 1 of 2 treatments: 1) hay treated with 10% molasses (DM basis) + water (to 35% DM; MOL) or 2) hay treated with 5% CaO (DM basis) + 10% molasses (DM basis) + water (to 35% DM; CAO). Cottonseed meal was provided at a rate of 0.3% of cattle BW/d (as fed basis). Data were analyzed using the MIXED procedure of SAS and pasture was the experimental unit. The model included the fixed effects of treatment and sex. Location and block were included as random effects. Initial and final BW were not affected by treatment (P = 0.573, P = 0.453; initial and final BW, respectively) or sex (P = 0.512, P = 0.670; initial and final BW, respectively). Additionally, no effects of treatment (P = 0.767) or sex (P = 0.285) were observed on ADG (average of 0.537 kg). In conclusion, bahiagrass hay treated with molasses alone or in combination with CaO failed to improve performance of growing beef cattle

scholarly journals California net energy system for Bos taurus indicus

2019 ◽  
Vol 3 (3) ◽  
pp. 991-998
Author(s):  
Mario Luiz Chizzotti ◽  
Sebastião de Campos Valadares Filho ◽  
Pedro Del Bianco Benedeti ◽  
Flávia Adriane de Sales Silva
Keyword(s):  
Body Weight ◽  
Beef Cattle ◽  
Bos Taurus ◽  
Energy Requirement ◽  
Energy System ◽  
Energy Requirements ◽  
Net Energy ◽  
Nutrient Requirements ◽  
Crossbred Cattle ◽  
Bos Taurus Indicus

Abstract The California net energy system (CNES) was the reference for the development of most energy requirement systems worldwide, such as Nutrient Requirements of Beef Cattle (NASEM, Nutrient requirements of beef cattle, 8th Revised ed, 2016) and Brazilian Nutrient Requirements of Zebu and Crossbred Cattle (Valadares Filho, S. C., L. F. C. Silva, M. P. Gionbelli, P. P. Rotta, M. I. Marcondes, M. L. Chizzotti, and L. F. Prados, BR-CORTE: nutrient requirements of zebu and crossbred cattle, 3rd ed, 2016). This review aimed to compare methods used by NASEM and BR-CORTE to estimate the energy requirements for beef cattle. The net energy requirements for maintenance (NEm) of BR-CORTE is based on empty body weight (EBW), whereas NASEM uses shrunk body weight (SBW), but the Bos taurus indicus presents 10% to 8% lower NEm than Bos taurus taurus. We have compared animals with different EBW and SBW but with same equivalent empty body weight/standard reference weight ratio (0.75), as both systems have suggested different mature weights. Both systems predicted similar net energy requirements for gain (NEg) for animals with 1.8 kg of daily gain. However, estimated empty body gain was lower for NASEM estimations when the same metabolizable energy for gain is available. For pregnancy and lactation of beef cows, the NEm and net energy requirements for pregnancy (NEp) of a Zebu cow estimated by BR-CORTE were lower than the values estimated by NASEM. Furthermore, the magnitude of differences between these systems regarding NEp increased as pregnancy days increase. The NASEM and BR-CORTE systems have presented similar values for energy requirement for lactation (0.72 and 0.75 Mcal/kg milk, respectively).

8 Effects of a Bovine Appeasing Substance Application at Weaning on Temperament and Growth of Bos Indicus Influenced Heifers

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 3-4
Author(s):  
Douglas G Viera ◽  
Juliana Ranches ◽  
Marcelo Vedovatto ◽  
Giovana G Pirota ◽  
Bruno I Cappellozza ◽  
...  
Keyword(s):  
Body Weight ◽  
Single Dose ◽  
Beef Cattle ◽  
Average Daily Gain ◽  
Bos Indicus ◽  
Cattle Herd ◽  
Synthetic Analogue ◽  
Skin Area ◽  
To Receive ◽  
Daily Gain

Abstract The objective of this study was to evaluate the effects of a synthetic analogue of the bovine appeasing pheromone (i.e. bovine appeasing substance; BAS) on growth and temperament of heifers. At weaning (d 0), 30 heifers (Aberdeen Angus ′ Nelore; 8 ± 1 mo) were stratified by body weight (199.8 ± 16 kg) and randomly assigned to receive a single dose of BAS (n = 15; SecureCattle; Nutricorp, Araras, SP, Brazil) or saline (CON; n = 15; saline 0.9% NaCl). Treatments (5 ml) were topically applied to the nuchal skin area of each animal on d0. Body weight was collected on d 0, 6, 15, 45, and 150. Chute score (1 to 5; 1 = calm, no movement; 5 = violent and continuous struggling) and chute entrance and exit score (1 to 3; 1 = slow; 3 = fast) were collected on d 0, 2, 6, 15, 45 and 150. Scores were averaged across 4 trained technicians. Data were analyzed using the MIXED procedure of SAS. Heifers assigned to BAS had greater (P &lt; 0.01) average daily gain (ADG) than heifers assigned to CON treatment from d 6 to 15 (2.35 and 1.88 kg/d ± 0.16) and from d 15 to 45 (1.79 vs. 1.56 kg/d ± 0.08). Heifers assigned to BAS had lower (P &lt; 0.01) chute entrance score on d 6, 15, and 45, and chute exit score on d 2 to 45 (P = 0.05) when compared to heifers assigned to CON. Additionally, heifers assigned to BAS tended (P = 0.08) to have lower chute score, from d 1 to 150 than heifers assigned to CON. The application of BAS at weaning improved heifers ADG, likely due to an improvement in temperament, suggesting that BAS application has calming effects in the beef cattle herd.

scholarly journals Effect of the g.98535683A > G SNP in the CAST gene on meat traits of Nellore beef cattle (Bos indicus) and their crosses with Bos taurus

Meat Science ◽  
2017 ◽  
Vol 123 ◽  
pp. 64-66 ◽  
Author(s):  
Cruz Elena Enriquez-Valencia ◽  
Guilherme Luis Pereira ◽  
Jessica Moraes Malheiros ◽  
Josineudson Augusto I.I. de Vasconcelos Silva ◽  
Lúcia Galvão Albuquerque ◽  
...  
Keyword(s):  
Beef Cattle ◽  
Bos Taurus ◽  
Bos Indicus ◽  
Cast Gene
Sign in / Sign up

Export Citation Format

Share Document