Effects of Megasphaera elsdenii administration on performance and carcass traits of finishing Bos indicus feedlot cattle

Abstract This study evaluated the effects of Megasphaera elsdenii administration at the beginning of the feedlot period on performance of Bos taurus indicus bulls. On d 0, 383 Nellore bulls (initial shrunk body weight 384 ± 29.2 kg; initial age = 24 ± 2 mo) were assigned to treatments in a randomized complete block design. Treatments consisted of 1) 14 d adaptation diet and transition to a finishing diet (CONT), 2) CONT plus oral administration of 20 mL of Lactipro-NXT (M. elsdenii) on d 0 of the study (MEG-14), 3) CONT diet, consisting of 6 d of adaptation diet plus oral administration of 20 mL of Lactipro-NXT on d 0 of the study (MEG-6), and 4) No adaptation diet and oral administration of 20 mL of Lactipro-NXT on d 0 of the study (MEG-0). Experimental period lasted 119 d. No treatment effects were observed for any of the performance parameters evaluated herein (P ≥ 0.15). Nonetheless, a treatment × wk interaction was observed for DM, NEm, and NEg intakes (P < 0.0001). For all these parameters, MEG-0 and MEG-6 had a reduced intake vs. MEG-14 and CONT in the first wk of the study (P ≤ 0.05). For the carcass traits, no effects were observed for HCW (P ≥ 0.24), whereas MEG-6 had a greater REA when compared with MEG-0 and MEG-14 (quadratic effect; P = 0.04) and MEG-administered bulls tended to have a greater BFT vs. CONT (P = 0.08). In summary, M. elsdenii administration at the beginning of the feedlot period did not improve performance, whereas reducing the length of the adaptation period for 6 d improved REA of finishing Bos taurus indicus bulls.

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Effect of hormonal growth promotants on palatability and carcass traits of various muscles from steer and heifer carcasses from a Bos indicus - Bos taurus composite cross

Australian Journal of Experimental Agriculture ◽

10.1071/ea05112 ◽

2008 ◽

Vol 48 (11) ◽

pp. 1415 ◽

Cited By ~ 13

Author(s):

R. Watson ◽

R. Polkinghorne ◽

A. Gee ◽

M. Porter ◽

J. M. Thompson ◽

...

Keyword(s):

Bos Taurus ◽

Vastus Lateralis ◽

Carcass Traits ◽

Bos Indicus ◽

Rectus Femoris ◽

Biceps Femoris ◽

Cooking Methods ◽

Triceps Brachii ◽

The Mean ◽

Psoas Major

The effect of several different hormonal growth promotant (HGP) implant strategies on the palatability and carcass traits of different muscles in beef carcasses was investigated using samples from heifer and steer carcasses from a Bos indicus composite breed. In experiment 1, there were seven different implant strategies evaluated in heifers that were given different combinations of up to three implants (implanted at weaning, during backgrounding and at feedlot entry). A total of 112 heifers were slaughtered and 11 muscles or portions were collected from both sides [Mm. adductor femoris, gracilus, semimembranosus, longissimus dorsi lumborum, triceps brachii caput longum, semispinalis capitis, serratus ventralis cervicis, spinalis dorsi, biceps femoris (syn. gluteobiceps), tensor fasciae latae, gluteus medius (both the ‘D’ and the ‘eye’ portions) rectus femoris, vastus intermedius, vastus lateralis and vastus medialis]. These muscles were used to prepare a total of 1030 sensory samples which were aged for either 7 or 21 days and frozen. Thawed samples were cooked using different cooking methods (grill, roast and stir frying) before being evaluated by a consumer taste panel that scored samples for tenderness, juiciness, like flavour and overall liking. Experiment 2 used the steer portion from the same calving, which were treated to a similar array of HGP strategies, except that they were given up to four implants between weaning and slaughter at ~3 years of age. In experiment 2, there was a total of 12 different HGP implant strategies tested. At boning, three muscles (Mm. psoas major, longisimuss dorsi thoracis and lumborum portions) were collected from each of 79 carcasses with a total of 237 steak samples that consumers tested as grilled steaks. For both experiments, the mean of the HGP implant strategies resulted in increased ossification scores (P < 0.05) and decreased marbling scores (P < 0.05) compared with the controls, with the effect on ossification being much larger in the older steer groups. In both experiments, the different HGP strategies decreased (P < 0.05) all sensory scores compared with the controls, for all cooking method and muscle combinations. In experiment 1, there was no interaction between the mean HGP effect and muscle (P > 0.05), and aging rates differed among the muscles (P < 0.05). In experiment 2, there was a significant (P < 0.05) muscle × HGP treatment interaction, with a decrease in tenderness score due to HGP implant strategies in the M. longisimuss thoracis and lumborum portions, compared with no significant effect in the M. psoas major. For both experiments, there were no significant differences among the different implantation strategies on sensory scores (P > 0.05).

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Inclusion of Yerba Mate (Ilex paraguariensis) Extract in the Diet of Growing Lambs: Effects on Blood Parameters, Animal Performance, and Carcass Traits

Animals ◽

10.3390/ani10060961 ◽

2020 ◽

Vol 10 (6) ◽

pp. 961

Author(s):

Richard R. Lobo ◽

Rafaela Vincenzi ◽

Danny A. Rojas-Moreno ◽

Annelise A. G. Lobo ◽

Caroline M. da Silva ◽

...

Keyword(s):

Dry Matter ◽

Block Design ◽

Carcass Traits ◽

Experimental Period ◽

Feed Additive ◽

Ilex Paraguariensis ◽

Yerba Mate ◽

Animal Performance ◽

Linear Quadratic ◽

Hematological Indices

This study aimed to evaluate levels of yerba mate (Ilex paraguariensis) extract (YME), as a feed additive in the diets of growing lambs on serum biochemical parameters and hematological indices, animal performance, body metrics and carcass traits. Thirty-six entire (nine per treatment), male growing lambs, weighing 23.8 ± 3.7 kg, were fed the experimental diets which were treatments consisting of increasing levels of YME (0, 1, 2, and 4% inclusion on a dry matter [DM] basis) during an experimental period of 53 days. The experiment was carried out in a randomized block design, which initial body weight was used as blocking factor and the results were analyzed by orthogonal contrasts (linear, quadratic, and cubic). Yerba mate extract did not change the general health status of the animals; however, inclusions of up to 2% of the extract increased globulins (p = 0.05) and white blood cell count, as segmented neutrophils (p = 0.02) and lymphocytes (p = 0.04). Additionally, inclusion of up to 2% YME increased dry matter intake, final weight gain, total and daily gain (p < 0.05), also tended to increase ribeye area and reduce fat thickness (p < 0.10); however, YME above 2% of inclusion reduced animal productive parameters (p < 0.05). In conclusion, levels up to 2% of YME were beneficial to the health and productive parameters of growing lambs.

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Influence of shade on panting score and behavioural responses of Bos taurus and Bos indicus feedlot cattle to heat load

Animal Production Science ◽

10.1071/an19013 ◽

2020 ◽

Vol 60 (2) ◽

pp. 305 ◽

Cited By ~ 1

Author(s):

A. M. Lees ◽

J. C. Lees ◽

V. Sejian ◽

M. L. Sullivan ◽

J. B. Gaughan

Keyword(s):

Treatment Group ◽

Observational Data ◽

Heat Load ◽

Bos Taurus ◽

Bos Indicus ◽

Observation Time ◽

Feedlot Cattle ◽

Night Time ◽

Treatment Groups ◽

Panting Score

Context Feedlot cattle can be negatively impacted by hot conditions, such that they have reduced performance and wellbeing. This study was conducted at the research feedlot located at The University of Queensland during a southern hemisphere summer (October to April). Aims The objective of this study was to evaluate the influence of shade on the behaviour and panting score of Bos taurus and Bos indicus feedlot cattle during summer. Methods Thirty-six steers (12 Angus, 12 Charolais and 12 Brahman) with an initial non-fasted liveweight of 318.5 ± 6.7 kg were used in a 154-day feedlot study consisting of two treatments: unshaded and shaded (3 m2/animal). Observational data were obtained for each steer at 2 h intervals between 0600 and 1800 hours daily from Day 1 to Day 154. Additional night time observational data were collected at 2-h intervals between 2000 and 0400 hours on 12 occasions. Data collected included activity (feeding, drinking, or ruminating), posture (standing or lying) and panting score. Panting scores were used to calculate a mean panting score for each breed × treatment group. Observational data were converted to a count for each breed × treatment group for each observation time point and were analysed using a binomial generalised linear model. Key results Maximum shade utilisation was the greatest at 1200 hours for Angus (85.5%), Charolais (32.7%) and Brahman (33.3%) steers. All breed × treatment groups exhibited a notable increase in mean panting score as heat load increased. Average increase in mean panting score was 0.36, where shaded Brahman exhibited the smallest increase (0.13) and unshaded Angus had the greatest increase (0.71). When heat load conditions were very hot (heat load index (HLI) ≥ 86) the mean panting score of all breed × treatment groups differed (P < 0.05). Conclusions Overall these results emphasise the importance of providing shade to feedlot cattle, irrespective of genotype. Implications These results further highlight the importance of providing shade to feedlot cattle. These results challenge the general perception that Bos indicus feedlot cattle do not require access to heat load alleviation strategies.

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Evaluation of sunflower meal on growth and carcass traits of finishing pigs

Ciência e Agrotecnologia ◽

10.1590/s1413-70542005000100026 ◽

2005 ◽

Vol 29 (1) ◽

pp. 208-215 ◽

Cited By ~ 2

Author(s):

Douglas de Carvalho Carellos ◽

José Augusto de Freitas Lima ◽

Elias Tadeu Fialho ◽

Rilke Tadeu Fonseca de Freitas ◽

Hunaldo Oliveira Silva ◽

...

Keyword(s):

Block Design ◽

Carcass Traits ◽

Experimental Period ◽

Experimental Unit ◽

Finishing Pigs ◽

Sunflower Meal ◽

Animal Science ◽

Randomized Block Design ◽

Crossbred Pigs ◽

Performance Trial

With the objective to evaluate the influence of increasing levels of inclusion of sunflower meal (SFM) solvent extraction (DM: 92.71%, CP: 27.50%, NDF: 43.57%, ADF: 32.96%, CF: 25.91%, EE: 3,08% and GE: 4390 kcal) on the performance and carcass characteristics of finishing swine, a performance trial was conducted in the Department of Animal Science of the Federal University of Lavras - MG. A total of 80 crossbred pigs (LD x LW) with initial weight of 62.20 ± 4.21 kg were utilized, one barrow and one gilt per experimental unit, allocated in a randomized block design. The treatments were represented by five diets with increasing levels of inclusion (0, 4, 8, 12 and 16%) of SFM. At the end of the experimental period, all pigs were slaughtered (99.80 ± 6.91kg) and submitted to the carcass evaluation by the Brazilian Method of Carcass Evaluation (ABCS, 1973). The increasing levels of SFM shown a linear reduction (P<0.05) in the feed intake, therefore all other variables, shown any significant effect. The carcass data evaluation also shown any significant effect (P>0.05) for any increasing levels of SFM in the diets, however, sex effect was found, in the barrows, which shown higher ETM, P2, AG and RCG and lower AOL in relation to the females In conclusion Sunflower meal should be included up to 16% in pig diet (isocaloric and isolysinic, basis ) with no major effects on growth performance or carcass traits of finishing pigs.

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Frecuencias alélicas para variantes SNP en el gen Nramp1 en bovinos infectados con Brucella abortus o clasificados por resistencia al patógeno

Ciencia y Tecnología Agropecuaria ◽

10.21930/rcta.vol10_num1_art:127 ◽

2009 ◽

Vol 10 (1) ◽

pp. 43

Author(s):

Fernando Cerquera M. ◽

Rodrigo Martínez S. ◽

Rubén Toro O. ◽

Jaime Tobón C. ◽

Jaime Gallego G. ◽

...

Keyword(s):

Single Nucleotide Polymorphism ◽

Brucella Abortus ◽

Bos Taurus ◽

Bos Indicus ◽

Natural Resistance ◽

Nucleotide Polymorphism ◽

Single Nucleotide ◽

Allelic Frequencies ◽

Bos Taurus Indicus

La resistencia natural a la brucelosis en bovinos ha sido asociada a factores genéticos, principalmente a algunos polimorfismos de nucleótido simple ubicados dentro del gen Nramp1. La presente investigación evalúa el efecto de variantes tipo polimorfismos de nucleótido simple presentes en regiones codificantes y en la región 3’UTR del gen Nramp1, en la clasificación de los animales como resistentes o susceptibles; además se determinan los genotipos predominantes en animales naturalmente infectados y comprobados como positivos por la presencia de anticuerpos anti Brucella abortus. Se establecieron las frecuencias genotípicas y alélicas para cinco polimorfismos de nucleótido simple identificados dentro del gen Nramp1 en animales de las razas blanco orejinegro (Bos taurus taurus) y cebú (Bos taurus indicus) y en muestras serológicamente positivas provenientes de animales cruzados (Bos taurus x Bos indicus). La determinación de genotipos se realizó mediante la metodología polimorfismo conformacional de cadena sencilla. Se realizó un ensayo de desafío infeccioso in vitro, para estimar la capacidad de los macrófagos bovinos para controlar la sobrevivencia bacterial, lo que permitió definir los individuos como resistentes o susceptibles. Los resultados sugieren una asociación significativa del SNP4 (p = 0,0506) con la variación para el fenotipo de susceptibilidad, pues se encontró el genotipo homocigoto (BB) en alta frecuencia en animales catalogados como resistentes y el genotipo heterocigoto (AB) en alta frecuencia en animales catalogados como susceptibles y en animales con títulos de anticuerpos anti Brucella abortus. Allelic frequencies for SNP variants in the gene Nramp1 in bovine infected with Brucella abortus or classified by resistance to the pathogen The natural resistance to brucellosis in cattle has been associated to genetic factors mainly to some single nucleotide polymorphism (SNP), located within Nramp1 gen. The current research has studied the effect of nucleotide variants to be found in coding regions and other one located in 3 non translated region of Nramp1 gene, on the animal classification as resistant or susceptible, moreover was identified the main genotypes to be found on the infected animals, confirmed as positives by antibody antibrucella titles. Was established the genotypic and allelic frequencies for five single nucleotide polymorphism in animals from blanco orejinegro (Bos taurus taurus) and zebu breeds (Bos taurus indicus) and serum samples belonging to positive crossbred animals (Bos taurus x Bos indicus). The genotype was defined by the methodology known as “single strand conformational polymorphism”. To estimate the macrophage capacity to control the bacterial survival, an in vitro assay was performed, which allowed define the phenotype as resistant or susceptible. The results suggest a significant association for SNP4 (p = 0.0506) with the phenotypic variation for resistant or susceptibility, because was found the genotype (BB) at higher frequency in susceptible animals and naturally infected animals, than those resistant animals.

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320 Carcass characteristics of Bos indicus-Bos taurus steers following BVDV type 1b challenge

Journal of Animal Science ◽

10.1093/jas/skz258.009 ◽

2019 ◽

Vol 97 (Supplement_3) ◽

pp. 6-6

Author(s):

Arthur Knowles ◽

Joe Paschal ◽

Chase Runyan ◽

Jason Sawyer ◽

Andy Herring

Keyword(s):

Feed Intake ◽

Fixed Effects ◽

Bos Taurus ◽

Clinical Symptoms ◽

Carcass Traits ◽

Bos Indicus ◽

Carcass Weight ◽

Post Challenge ◽

Diarrhea Virus ◽

Vaccine Type

Abstract Bovine Viral Diarrhea virus (BVDV), is a component of bovine respiratory disease (BRD) worldwide. Documentation of animal genetic influences and performance variability specific to BVDV challenge is limited. This study evaluated individual animal effects in the 14 d following BVDV Type 1b intranasal challenge in yearling, Nellore-Angus (Bos indicus-Bos taurus) F2 and F3 crossbred steers (n = 363) on carcass traits 180 d post-challenge. Prior to challenge steers were confirmed to be free of BVDV infection with families balanced across non-vaccinated control, killed (KV), or modified-live (MLV) commercial BRD vaccines. Hot carcass weight (HCW), adjusted fat thickness (AFT), longissimus muscle area (REA) and marbling score (MARB) were analyzed through mixed models with sire and pen(year) as random effects; potential fixed effects of vaccine, type of cross, pyrexia status, clinical sign presentation, and levels of feed intake and ADG 14 d post-challenge were investigated. Vaccine influenced AFT (P = 0.016); MLV steers had 0.26 cm less AFT than KV steers. Marbling was affected by type of cross (P = 0.023) with up to 0.60 marbling scores higher (P < 0.05) in some parental combinations; an interaction between type of cross and pyrexia status also affected MARB (P = 0.017) with one parental combination having higher MARB associated with pyrexia. Hot carcass weight was not affected by pyrexia, but was affected by feed intake (P = 0.019), with steers in the highest vs. lowest category averaging 24.0 kg heavier. No animals presented morbidity signs severe enough for therapeutic treatment, yet presence of mild clinical symptoms affected REA (P = 0.012), resulting in 3.4 cm2 lower REA, however, this pattern was inconsistent among feed intake levels. This study affirms the complexity of health impacts on beef carcass traits and the need for improved study of subclinical illness in beef production systems.

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

Journal of Animal Science ◽

10.1093/jas/skz053.042 ◽

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

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223 PREANTRAL FOLLICLES POPULATION IN BOS TAURUS INDICUS AND BOS TAURUS TAURUS FEMALES

Reproduction Fertility and Development ◽

10.1071/rdv22n1ab223 ◽

2010 ◽

Vol 22 (1) ◽

pp. 269

Author(s):

K. C. F. Silva ◽

G. M. G. Santos ◽

L.S. Siloto ◽

M. F. Hertel ◽

E. R. Andrade ◽

...

Keyword(s):

Granulosa Cells ◽

Bos Taurus ◽

Science And Technology ◽

Bos Indicus ◽

Histological Evaluation ◽

National Council ◽

Crown Rump Length ◽

Preantral Follicles ◽

Oocyte Yield ◽

Bos Taurus Indicus

Bos taurus indicus females provide a greater in vivo oocyte recovery (2-4 times more) in comparision with Bos taurus taurus. This aspect has strongly contributed for the success of the embryo industry in Brazil. Little information is available to explain this difference. Our objective was to test the hypothesis that the difference in oocyte yield is a result of higher numbers of preantral follicles in the ovaries of B. indicus females. Ovaries (n = 44) of fetuses aging from 180 to 240 days and of heifers from 20 and 24 months were collected from Bos taurus indicus (Nelore) and Bos taurus taurus (Aberdeen Angus) females at a slaughterhouse. Fetal age was estimated from the crown-rump length (Evans HE and Sack WO 1973 Anat. Hist. Embryol. 2, 11-45). Ovaries from Nelore fetuses (n = 10) and heifers (n = 12) and Aberdeen Angus fetuses (n = 10) and heifers (n = 12) were cut longitudinally into two halves, fixed in Bouin’s solution, and processed for histological evaluation. The ovarian halves were dehydrated in alcohol, cleared with xylene, embbebed in paraffin, and serially sectioned at 7 μm. Every 120th section was mounted and stained with periodic acid Schiff and hematoxylin. The number of preantral follicles was estimated through the counting of follicles in each section using the nucleus of the oocyte as a marker and a correction factor (Gougeon A and Chainy GBN 1987 J. Reprod. Fertil. 81, 433-442). Only 1 ovary per female was analyzed. Preantral follicles were classified according to the developmental stage as primordial (1 layer of flattened granulosa cells surrounding the oocyte), primary (1 layer of cuboidal granulosa cells), or secondary (2 or more layers of cuboidal granulosa cells), and as normal or degenerated according to their morphological appearance. The number of preantral follicles was not normally distributed and was compared using the Mann-Whitney test. There was no difference (P > 0.05) between the average number of preantral follicles in the ovaries of Bos indicus and Bos taurus females. The average number of preantral follicles per female was 143 929 ± 253 (mean ± SD) and 285 155 ± 570 for Bos taurus and Bos indicus fetuses, respectively, and 76 851 ± 280 and 109 673 ± 293 for Bos taurus and Bos indicus heifers (P > 0.05), respectively. A large variation in numbers of preantral follicles was observed among individuals within the same category and between breeds. Our results suggest that there might be differences in mechanisms controlling follicle development after the preantral stage accounting for the greater oocyte yield from Bos indicus females. This work was supported by grants from the Universidad Nacional del Litoral (CAI+D program), Universidad Nacional de Lomas de Zamora, the Argentine National Agency for the Promotion of Science and Technology (ANPCyT), and the Argentine National Council for Science and Technology (CONICET).

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108 Synchronization and artificial insemination of South African communal cattle

Reproduction Fertility and Development ◽

10.1071/rdv33n2ab108 ◽

2021 ◽

Vol 33 (2) ◽

pp. 161

Author(s):

T. L. Magopa ◽

M. L. Mphaphathi ◽

T. Mulaudzi ◽

F. V. Ramukhithi ◽

M. M. Tshabalala ◽

...

Keyword(s):

Sperm Motility ◽

Assisted Reproductive Technologies ◽

Bos Taurus ◽

Body Condition Score ◽

Bos Indicus ◽

Prostaglandin F2α ◽

Reproductive Technologies ◽

Computer Assisted ◽

Bos Taurus Indicus ◽

Oestradiol Benzoate

The present study aimed to evaluate an oestrous synchronization protocol and oestrus response before AI in cows from an organised communal production system. A total of 74 cows Bos indicus (Brahman) and Bos taurus/indicus hybrid (Nguni) type from different communal farmers were screened based on: age (3 to 8 years), body condition score of ≥3 (1–5 scale), not pregnant (excluding heifers), 90 days postpartum, number of parities, good mothering ability, and negative for contagious abortion. Selected cows were subjected to a 9-day OvSynch+CIDR protocol. In brief, the protocol included the insertion of controlled intravaginal drug release (CIDR®, Pfizer Laboratories) devices in the reproductive tract (vagina) containing 1.9g of progesterone in each cow on Day 0 with first oestradiol benzoate (Oestradiol benzoate®, VTech) 2-mL intramuscular (IM) injection. Pregnant mare serum gonadotrophin (PMSG; Chronogest®, Intervet International B.V.) 2.5-mL (IM) injection on Day 5. Removal of CIDR and (IM) injection of prostaglandin F2α (PGF2α; Estrumate®, Intervet South Africa (Pty.) Ltd.) 2mL on Day 8. Following CIDR removal, a heat mount detector (Kamar®) was applied on the individual cow’s tail head for oestrus observation (signs of heat) with second oestradiol benzoate 1-mL (IM) injection on Day 9. AI was performed 36h following withdrawal of the CIDR. Frozen/thawed semen from Bonsmara bulls (n=2) of known and proven fertility was used for AI. The GameteTek Cryo-Mobile laboratory was used during thawing of semen straws. and sperm motility and morphological traits were immediately evaluated by computer-assisted sperm analysis (Sperm Class Analyzer®) before each individual cow was inseminated. Pregnancy diagnosis was performed 90 days after timed AI by ultrasound and transrectal palpation. Data were analysed using the logistic regression procedure of SAS (SAS Institute Inc.), with synchronisation response and conception being treated as binary response variables. All cows were synchronized successfully and an oestrus response rate of 100% was recorded. Pregnancy rates were similar (37.8% vs. 38.9%) for both Bos indicus and Bos taurus/indicus hybrid cattle. Bulls total sperm motility of ≥75% were recorded, following thawing of semen straws. Thus, there was no effect of bull on pregnancy. In conclusion, acceptable oestrus synchronization response was achieved in this communal setup. Superior genetic materials can be successfully introduced through assisted reproductive technologies in organised communal production systems.

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