197 The use of photostimulation to enhance oocyte cytoplasmic maturation

2020 ◽  
Vol 32 (2) ◽  
pp. 227
Author(s):  
C. M. Checura ◽  
S. L. Pratt ◽  
L. V. Campbell ◽  
K. Farmer ◽  
G. Loughlin ◽  
...  
Keyword(s):  
Embryonic Development ◽  
Repeated Measures ◽  
Fixed Effects ◽  
Culture Medium ◽  
Near Infrared ◽  
Random Effect ◽  
Monochromatic Light ◽  
High Humidity ◽  
Stage Of Development ◽  
Cytoplasmic Maturation

Phototherapy uses monochromatic light from low-power lasers and light-emitting diodes (LEDs) to modulate biological processes. It has been proposed that the red-to-near infrared optical region (~600-1000nm) enhances cellular metabolic activity by activation of the mitochondrial respiratory chain. However, photostimulation induces the generation of oxide free radicals and could create oxidative stress in exposed cells. The main objective was to use photostimulation to affect the cumulus-oocyte complex metabolic state, aiming to enhance cytoplasmic maturation rates and subsequent embryonic development. A secondary objective was to determine the toxicity of the proposed photostimulation protocol. Abattoir-derived ovaries were used. All media was from IVF Biosciences (Falmouth, Cornwall, UK). Follicles 2 to 6mm in diameter were aspirated. Oocytes with compact cumulus and homogeneous cytoplasm were selected, and 50 oocytes/well were placed in invitro maturation medium (0h) and incubated at 38.5°C in 5% CO2 in air with high humidity in the presence (treatment=exposure for 2min to super-bright LED 1 and 2h after the beginning of maturation; LED wavelength of 660-665 nm; NTE30041; NTE Electronics Inc.) or absence (Control) of light. After maturation (22h), oocytes were split into two wells (25 oocytes/well) and subjected to IVF with semen from two different bulls for 18 to 20h. Cumulus cells were separated by vortexing, zygotes were placed in invitro culture medium, and incubated at 38.5°C in 5% CO2 in air with high humidity. Culture medium was renewed every 48h. Cleavage, morula, and blastocyst rates were recorded as a percentage of the number of oocytes subjected to IVF per treatment. The experiment was replicated 4 times. Statistical analysis was conducted using the Mixed procedure (SAS 9.4, SAS Institute Inc.) with repeated-measures and autoregressive covariance. The model's random effect was well within treatment. Fixed effects were bull, stage of development, and treatment. There was no difference (P=0.8) between treatments for any stage of development measured (cleavage: 76.4±2.7 vs. 74.8±4.1; morula: 36.1±4.8 vs. 35.9±5.8; blastocyst: 20.8±3.2 vs. 20.6±4.4 for control and treatment respectively; mean±s.e.). Sire affected development: bull 1 had a greater percentage (P<0.05) cleavage (82.9±0.02 vs. 68.3±0.02), morula (42.6±0.05 vs. 29.4±0.04), and blastocyst (27.8±0.04 vs. 13.6±0.01) development than bull 2. There was no treatment×bull interaction (P=0.9). In conclusion, there were no stimulatory or toxic effects of this preliminary photostimulation protocol. Further research is needed to develop an optimal protocol that shows a metabolic effect and, potentially, an enhancement of invitro cytoplasmic maturation rates and subsequent embryonic development.

scholarly journals PSVIII-17 Assessment of conformational changes across three parities in sows

2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 221-222
Author(s):  
Melanie D Trenhaile-Grannemann ◽  
Ronald M Lewis ◽  
Stephen D Kachman ◽  
Kenneth J Stalder ◽  
Benny E Mote
Keyword(s):  
Body Size ◽  
Body Length ◽  
Conformational Changes ◽  
Repeated Measures ◽  
Fixed Effects ◽  
Random Effect ◽  
Joint Angles ◽  
Body Depth ◽  
Conformation Changes ◽  
Over Time

Abstract Conformation-based sow selection is performed prior to reaching mature size, yet little is known about how conformation changes as growth continues. To assess conformation changes, 9 conformational traits were objectively measured at 12 discrete time points between 112 d of age and parity 3 weaning on 622 sows in 5 cohorts. The 9 traits included 5 body size traits (body length, body depth at the shoulder and flank, and height at the shoulder and flank) and 4 joint angles (knee, hock, and front and rear pastern). Data were analyzed with a repeated measures model (SAS V 9.4) including cohort and time point as fixed effects, sire as a random effect, and heterogeneous compound symmetry as the covariance structure. Sire variance ranged from 0.16 (body depth shoulder) to 2.00 (body length) cm2 for body size traits and 2.28 (rear pastern) to 4.22 (front pastern) degrees2 for joint angles. Cohort had an effect on all traits (P < 0.05). All traits displayed changes over time (P < 0.001). Size traits increased between 112 d of age and parity 3 weaning (64.16 vs. 107.57 cm, 26.62 vs. 44.14 cm, 23.32 vs. 36.92 cm, 46.10 vs. 73.55 cm, 49.36 vs. 77.47 cm for body length, body depth shoulder and flank, and height shoulder and flank, respectively); however, they fluctuated within parity by increasing during gestation and decreasing at weaning. Knee angle decreased (164.12 vs. 150.72 degrees) while fluctuating within parity by decreasing in the second half of gestation and increasing after weaning. Front and rear pastern angles decreased over time (60.89 vs. 53.74 degrees and 64.64 vs. 55.50 degrees for front and rear pastern, respectively), while biologically negligible change was observed in hock angle (148.63 vs. 147.48 degrees). Sow conformation changes throughout life, and these changes may require consideration when making selection decisions.

305 Methane Emissions and Apparent Total Tract Nutrient Digestibility of Feedlot Beef Steers Under Intensive Management with or Without an Added Nutritional Packet

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 166-167
Author(s):  
Andrea M Osorio ◽  
Kaue T Tonelli Nardi ◽  
Igor Gomes Fávero ◽  
Kaliu G Scaranto Silva ◽  
Kymberly D Coello ◽  
...  
Keyword(s):  
Treatment Period ◽  
Repeated Measures ◽  
Fixed Effects ◽  
Block Design ◽  
Random Effect ◽  
Methane Emissions ◽  
Nutrient Digestibility ◽  
Experimental Unit ◽  
Beef Steers ◽  
Ch4 Production

Abstract The effects of a nutritional packet were evaluated on CH4 emissions and apparent total tract nutrient digestibility of feedlot beef steers. Thirty Angus-crossbred steers (BW = 542 ± 8.4 kg) were used in a randomized complete block design and allocated into pens equipped with SmartFeed (C-Lock; 15 steers/treatment). Steers were consuming a steam-flaked corn-based diet (88% concentrate DM basis) ad libitum for the last 65 d on feed, and received the following treatments: 1) control and 2) a nutritional packet [0.29% DM basis; live yeast (Saccharomyces cerevisiae; 8.7 Log CFU/g); Vitamin C (5.4 g/kg); Vitamin B1 (13.33 g/kg); NaCl (80 g/kg); KCl (80 g/kg)]. Methane emissions and apparent total tract nutrient digestibility were measured during 3 periods with 5-d of collections each. Gas emissions from steers were measured utilizing the SF6 tracer technique. Feed and fecal samples were collected once and twice (0700 h and 1600 h) daily, respectively, to determine digestibility of nutrients using iNDF as an internal marker. Steer was considered the experimental unit. Data were analyzed as repeated measures using the MIXED procedure of SAS with the fixed effects of treatment, period, and their interaction, and the random effect of block. No treatment × period interactions (P ≥ 0.125) were observed for DMI and any of the CH4 production variables (g/day, g/kg BW0.75, g/nutrient intake, and g/nutrient digested). Moreover, treatments did not affect digestibility of DM, OM, or ADF (P ≥ 0.300); however, digestibility of NDF was increased for treated cattle (P = 0.013), which resulted in a tendency (P = 0.098) to decrease CH4 production in g per kg NDF intake and decreased (P = 0.020) grams CH4 per kg NDF digested. The nutritional packet may be altering ruminal fermentation on intensively managed steers and improving fiber digestibility, which can have benefits on CH4 emission intensity.

scholarly journals Long-Term Testosterone Therapy Improves Cardiometabolic Function and Reduces Risk of Cardiovascular Disease in Men with Hypogonadism

2017 ◽  
Vol 22 (5) ◽  
pp. 414-433 ◽  
Author(s):  
Abdulmaged M. Traish ◽  
Ahmad Haider ◽  
Karim Sultan Haider ◽  
Gheorghe Doros ◽  
Farid Saad
Keyword(s):  
Repeated Measures ◽  
Fixed Effects ◽  
Random Effect ◽  
Treated Group ◽  
Myocardial Infarctions ◽  
Control Group ◽  
Cv Disease ◽  
High Level ◽  
Changes Over Time

Objectives: In the absence of large, prospective, placebo-controlled studies of longer duration, substantial evidence regarding the safety and risk of testosterone (T) therapy (TTh) with regard to cardiovascular (CV) outcomes can only be gleaned from observational studies. To date, there are limited studies comparing the effects of long-term TTh in men with hypogonadism who were treated or remained untreated with T, for obvious reasons. We have established a registry to assess the long-term effectiveness and safety of T in men in a urological setting. Here, we sought to compare the effects of T on a host of parameters considered to contribute to CV risk in treated and untreated men with hypogonadism (control group). Patients and Methods: Observational, prospective, cumulative registry study in 656 men (age: 60.7 ± 7.2 years) with total T levels ≤12.1 nmol/L and symptoms of hypogonadism. In the treatment group, men (n = 360) received parenteral T undecanoate (TU) 1000 mg/12 weeks following an initial 6-week interval for up to 10 years. Men (n = 296) who had opted against TTh served as controls. Median follow-up in both groups was 7 years. Measurements were taken at least twice a year, and 8-year data were analyzed. Mean changes over time between the 2 groups were compared by means of a mixed-effects model for repeated measures, with a random effect for intercept and fixed effects for time, group, and their interaction. To account for baseline differences between the 2 groups, changes were adjusted for age, weight, waist circumference, fasting glucose, blood pressure, and lipids. Results: There were 2 deaths in the T-treated group, none was related to CV events. There were 21 deaths in the untreated (control) group, 19 of which were related to CV events. The incidence of death in 10 patient-years was 0.1145 in the control group (95% confidence interval [CI]: 0.0746-0.1756; P < .000) and 0.0092 in the T-treated group (95% CI: 0.0023-0.0368; P < .000); the estimated difference between groups was 0.0804 (95% CI: 0.0189-0.3431; P < .001). The estimated reduction in mortality for the T-group was between 66% and 92%. There were also 30 nonfatal strokes and 26 nonfatal myocardial infarctions in the control group and none in the T-treated group. Conclusion: Long-term TU was well tolerated with excellent adherence suggesting a high level of patient satisfaction. Mortality related to CV disease was significantly reduced in the T-group.

scholarly journals Leptin has concentration and stage-dependent effects on embryonic development in vitro

Reproduction ◽  
2006 ◽  
Vol 132 (2) ◽  
pp. 247-256 ◽  
Author(s):  
Muren Herrid ◽  
Van Ly Nguyen ◽  
Geoff Hinch ◽  
James R McFarlane
Keyword(s):  
Embryonic Development ◽  
Embryo Development ◽  
Culture Medium ◽  
Leptin Receptor ◽  
Inhibitory Effect ◽  
Differential Sensitivity ◽  
Cell Stage ◽  
Paracrine Signalling ◽  
Stage Of Development

There is accumulating evidence that leptin may be directly involved in pre-implantation embryonic development, however, it is unclear whether there is a concentration and stage-dependent regulatory pattern. In this study, the addition of 10 ng/ml human recombinant leptin to the culture medium significantly increased the percentage of two-cell mouse embryos that developed into blastocysts and hatched blastocysts, whereas in the presence of 100 ng/ml leptin, the development rate was significantly inhibited. The total cell numbers in the hatched blastocysts were significantly higher in the presence of 10 ng/ml leptin compared with controls and higher concentrations. The differential sensitivity to leptin was found to vary among embryos at different stages of development. Supplementation of leptin (10 ng/ml) to culture medium at two- to eight-cell stages resulted in a consistent stimulatory effect on embryo development. Most interestingly, the inhibitory effect of high leptin concentration (100 ng/ml) on embryo development was diminished when it was added to the culture medium at the eight-cell stage of development. The concentration-dependent regulation pattern was confirmed using sheep embryos, under similar conditions although sheep embryos appeared to be more sensitive in responding to leptin. Having established the effect of exogenous leptin on embryo development, the expression pattern of leptin and its receptors were also investigated. Leptin mRNA was not detected in mouse two-, four-, eight-cell and blastocyst stage embryos, whereas three isoforms of leptin receptor (Ob-Ra, Ob-Rb and Ob-Re) were identified in these cells, indicating that leptin is likely to modulate embryo development via a paracrine signalling system.

scholarly journals Efficacy of parent-mediated communication-focused treatment in toddlers with autism (PACT) delivered via videoconferencing: a randomised controlled trial study protocol

BMJ Open ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. e044669
Author(s):  
Lucie Jurek ◽  
Pauline Occelli ◽  
Angelique Denis ◽  
Anouck Amestoy ◽  
Thierry Maffre ◽  
...  
Keyword(s):  
Randomised Controlled Trial ◽  
Repeated Measures ◽  
Urban Areas ◽  
Fixed Effects ◽  
Controlled Trial ◽  
Random Effect ◽  
Autism Spectrum ◽  
Health Priorities ◽  
Preschool Period ◽  
Randomised Controlled

IntroductionIntervention in the preschool period is currently recommended for autism spectrum disorder. Therapies delivered by parents are particularly suitable for young children. Preschool Autism Communication Trial (PACT) is a parent-mediated therapy that has shown a significant and sustained impact on autism symptom reduction. However, access to such evidence-based therapies for families is limited due to autism centres located in large urban areas. Using videoconferencing to deliver PACT training to parents may improve accessibility for families living in underserved areas.Methods and analysisThis single-blind randomised controlled trial, involving six sites in France, will investigate the efficacy of a telehealth, videoconferencing-based, parent-mediated PACT therapy on autism symptoms, over a 12-month period. It will compare PACT plus treatment as usual (TAU) against TAU only in a cohort of 238 toddlers (119 per group) aged 18–36 months at inclusion and living with their families more than 40 min away from the specialist centres for autism. Primary outcome will include change of overall autism score on the Autism Diagnostic Observation Scale (ADOS) at 12 months. Secondary outcomes will measure change in child skills, child functioning, impact on parents (stress, health, priorities) and implementation characteristics. Repeated measures analyses will be used to test the effect of PACT intervention on the overall ADOS module 1 score over the 12-month study period. Linear mixed models will be used with time, treatment allocation and the interaction between treatment and time as fixed effects and individual variation as random effect.Ethics and disseminationThis protocol (V.5, date: 25 October 2019) is approved by the French National Review Board (reference no 2018-A02516-49). The results will be disseminated via peer-reviewed journalsTrial registration numberNCT04244721.

scholarly journals Effect of bupivacaine liposome suspension administered as a local anesthetic block on indicators of pain and distress during and after surgical castration in dairy calves

2021 ◽  
Author(s):  
Miriam S Martin ◽  
Michael D Kleinhenz ◽  
Abbie V Viscardi ◽  
Andrew K Curtis ◽  
Blaine T Johnson ◽  
...  
Keyword(s):  
Gait Analysis ◽  
Local Anesthetic ◽  
Repeated Measures ◽  
Fixed Effects ◽  
Treatment Time ◽  
Random Effect ◽  
Serum Cortisol ◽  
Nerve Blocks ◽  
Liposome Suspension ◽  
Long Acting

Abstract Castration is a routine procedure performed on beef and dairy operations in the U.S. All methods of castration cause behavioral, physiologic, and neuroendocrine changes associated with pain. The American Veterinary Medical Association and the American Association of Bovine Practitioners recommend that anesthesia and analgesia be administered at castration. The objective of this study was to evaluate the effectiveness of bupivacaine liposome suspension a novel, long-acting, local anesthetic administered as a nerve block at castration. The authors chose to investigate this novel formulation as an alternative to current industry standards using lidocaine nerve blocks alone, or in combination with meloxicam. Thirty male Holstein calves, 16-20 weeks of age, were enrolled and randomly assigned to 1 of 4 treatment groups prior to surgical castration: 1) bupivacaine liposome suspension block + oral placebo (BUP); 2) lidocaine block + oral placebo (LID); 3) lidocaine block + oral meloxicam (1 mg/kg) (LID + MEL); and 4) saline block + oral placebo (CON). Biomarkers were collected at -24 h and from 0 to 120 hours post-castration and included infrared thermography, pressure mat gait analysis, chute defense and behavior scoring (pain and activity), and blood sampling for serum cortisol and prostaglandin E2 metabolites (PGEM). Responses were analyzed using repeated measures, with calf nested in treatment as a random effect, and treatment, time, and their interaction designated as fixed effects. Results from pressure mat gait analysis show the CON had a shorter front limb stance time from baseline (-8.73%; 95% CI: -24.84 to 7.37%) compared to BUP and LID + MEL (&gt; 5.70%; 95% CI: -22.91 to 23.79%) (P &lt; 0.03). The CON tended to have an increase in front limb force from baseline (6.31%; 95% CI: -1.79 to 14.41%) compared to BUP, LID, and LID + MEL (&lt; -5.06%; 95% CI: -14.22 to 0.95%) (P &lt; 0.04). The CON displayed higher counts of hunched standing (2.00; 95% CI: 1.68 to 2.32) compared to LID + MEL (1.43; 95% CI: 1.13 to 1.72) (P = 0.05). The CON had higher cortisol concentrations at 24 h (7.70 ng/mL; 95% CI: 1.52 to 13.87 ng/mL) relative to BUP (3.11 ng/mL; 95% CI: -2.56 to 8.79 ng/mL) (P = 0.002). At 4 and 24 h, LID + MEL had lower PGEM concentrations from baseline (-32.42% and -47.84%; 95% CI: -78.45 to -1.80%) compared with CON (27.86% and 47.63%; 95% CI: 7.49 to 82.98%) (P &lt; 0.02). Administration of bupivacaine liposome suspension as a local anesthetic block at the time of castration was as effective at controlling pain as a multi-modal approach of lidocaine and meloxicam.

145 OVIDUCTAL EXPRESSION OF GENES INVOLVED IN GROWTH FACTOR, CYTOKINE, HORMONE, AND WNT SIGNALING DURING THE EARLY ESTROUS CYCLE OF THE COW

2016 ◽  
Vol 28 (2) ◽  
pp. 202
Author(s):  
P. Tribulo ◽  
L. G. Siqueira ◽  
P. J. Hansen
Keyword(s):  
Gene Expression ◽  
Embryonic Development ◽  
Corpus Luteum ◽  
Fixed Effects ◽  
Reproductive Tract ◽  
Expression Patterns ◽  
Random Effect ◽  
Housekeeping Genes ◽  
Cell Types ◽  
Endocrine Control

Knowledge of the molecules used by the maternal reproductive tract to regulate development of the pre-implantation embryo, called embryokines, is largely incomplete. To identify possible candidates for this function, an experiment was conducted to assess expression patterns during the first 7 days after ovulation for 92 genes that could be involved in control of development. Included were genes for 27 growth factors, 11 cytokines, 22 interleukins, 3 hormones, 19 WNT ligands, and 9 WNT regulatory molecules. Cows were slaughtered at Days 0, 3, 5, and 7 relative to predicted ovulation. Reproductive tracts were obtained and transversal sections from the isthmus of oviducts ipsi- and contralateral to the corpus luteum were harvested for gene expression analysis. Abundance of specific mRNA molecules was determined using the NanoString nCounter analysis system (NanoString Technologies, Seattle, WA, USA). Data were normalized against 6 housekeeping genes (ACTB, ERK1, GAPDH, RPL19, SLC30A6, SUZ12) and internal positive controls. Genes were considered expressed if the number of reads was greater than 2 standard deviations above the mean of negative controls. Data were analysed by ANOVA using the GLM procedure of SAS (SAS Institute Inc., Cary, NC, USA) with day, side, and day × side as fixed effects, and cow as random effect. Side did not have any significant effect so data were analysed without side and day × side in the model. In contrast to what was observed earlier for endometrium (P. Tribulo and P. J. Hansen, unpublished data), we found no difference in gene expression between oviducts ipsi- and contralateral to the corpus luteum. Overall, there was wide variation in the magnitude of gene expression. Among the 20 most expressed genes, average reads varied from 164 to over 10 726. All genes were detected at Days 0, 3, and 7 but only 67 of the 92 genes were expressed at Day 5. The 10 highest-expressed genes were CTGF, CXCL3, CXCL10, CXCL12, GRO1, IGF2, IK, SFRP1, WNT5A, and WNT6. Of these, CTGF, CXCL12, IGF2, IK, HDGF, WNT5A, and CXCL3 were within the 10 highest expressed at all days (P. Tribulo and P. J. Hansen, unpublished data). There were only 6 genes whose expression was significantly affected by day. Expression was highest at oestrus (VEGFA), Day 5 (GRO1, SFRP1) or Day 7 (BMP4, IK, WNT16). This experiment identifies some potential maternal regulators of embryonic development. Expression of most of these putative embryokine genes did not vary with stage of the oestrous cycle, suggesting that expression is either not under endocrine control or varies between cell types within the oviduct. Further studies are needed to determine the effect of these maternally secreted molecules on embryonic development. Study was supported by the National Institutes of Health (HD080855).

scholarly journals Evaluation of Brassica carinata meal as a protein supplement for growing beef heifers1,2

2019 ◽  
Vol 97 (10) ◽  
pp. 4334-4340
Author(s):  
Tessa M Schulmeister ◽  
Martin Ruiz-Moreno ◽  
Gleise M Silva ◽  
M Garcia-Ascolani ◽  
Francine M Ciriaco ◽  
...  
Keyword(s):  
Repeated Measures ◽  
Fixed Effects ◽  
Day Treatment ◽  
Block Design ◽  
Random Effect ◽  
Brassica Carinata ◽  
Protein Supplement ◽  
Oilseed Crop ◽  
Beef Heifers ◽  
Effect Of Treatment

Abstract Brassica carinata is a new oilseed crop in Florida with the potential of producing high-quality jet biofuel. A high-protein meal (~40% crude protein; CP) is obtained as a byproduct of oil extraction; however, limited research is available on the utilization of this meal as a protein supplement for beef cattle. A generalized randomized block design was used to evaluate the effects of supplementation with B. carinata meal pellets on performance and attainment of puberty in growing beef heifers consuming bermudagrass hay (Cynodon dactylon) ad libitum. Sixty-four Angus crossbred heifers (240 ± 39 kg initial body weight; BW) were stratified and blocked (2 blocks: light and heavy) by initial BW and randomly allocated into 18 pens over 2 consecutive years (10 in year 1 and 8 in year 2). Within block, pens were randomly assigned to 1 of 2 treatments: 0 (CTL) or 0.3% of BW/d (as fed) of B. carinata meal pellets (BCM). Blood samples and BW were collected weekly for 70 d, before daily supplementation. Data were analyzed using PROC MIXED of SAS with repeated measures. Model included the fixed effects of treatment, day, treatment × day interactions, block, and block × treatment interactions, with the random effect of year. Plasma was analyzed for concentrations of progesterone, triiodothyronine (T3), thyroxine (T4), ceruloplasmin (Cp), and haptoglobin (Hp). An effect of treatment was observed (P ˂ 0.01) for ADG between CTL (0.14 kg) and BCM (0.42 kg). There was no treatment or block (P > 0.05) effect for concentrations of T3, T4, or Hp; however, there was an effect of day (P < 0.01) for T3, T4, and Cp. An effect of treatment (P ˂ 0.01) was observed for Cp, with CTL having greater concentrations compared with BCM. Time to attainment of puberty did not differ (P = 0.93) between treatments. Feeding B. carinata meal as a protein supplement at 0.3% of BW/d is a viable option for increasing ADG of growing beef heifers, without affecting attainment of puberty, thyroid hormone status, or eliciting an acute phase response.

scholarly journals 107 Influence of chronic melatonin supplementation on bovine testis physiology

2020 ◽  
Vol 98 (Supplement_2) ◽  
pp. 42-42
Author(s):  
Brittni P Littlejohn ◽  
Kayla B Mercer ◽  
Karrigan J Bowers ◽  
Riley D Messman ◽  
Zully Contreras-Correa ◽  
...  
Keyword(s):  
Blood Flow ◽  
Body Weight ◽  
Ambient Temperature ◽  
Repeated Measures ◽  
Fixed Effects ◽  
Treatment Time ◽  
Random Effect ◽  
Age Groups ◽  
Total Blood ◽  
Left And Right

Abstract The objective was to evaluate the influence of melatonin supplementation on bovine testis biometrics, thermoregulation, and blood flow in two age groups. Mature and peri-pubertal bulls received four subdermal 24 mg melatonin implants (MEL; n = 5 and n = 6, respectively) or no implants (CON; n = 5 and n = 6, respectively) every 30 ± 4 d for 120 ± 5 d. Body weight, scrotal circumference (SC), testes temperature (average temperature of left and right testes as quantified with thermal imaging), and total testicular artery blood flow (TBF; total blood flow to left and right testes as measured with Doppler ultrasonography) were evaluated on d 60, 90, and 120 ± 4. On d 120, peri-pubertal bulls were castrated and total testes weight (TTW) determined. Data were analyzed using MIXED procedures of SAS specific for repeated measures with treatment, time, and the interaction as fixed effects and sire (peri-pubertal only) as a random effect. On d 120, peri-pubertal bull data were analyzed using MIXED procedures of SAS with treatment as a fixed effect and sire as a random effect, and relationships of TBF, SC, TTW, testes temperature, and ambient temperature assessed using CORR procedures of SAS. Body weight, testes temperature, TBF, and TBF as a proportion of SC changed over time in peri-pubertal (P &lt; 0.05) but not mature (P &gt; 0.05) bulls. On d 120, TBF was increased (P = 0.05) and TBF as a proportion of TTW tended (P = 0.10) to be increased in MEL (95.48 ± 14.63 mL/min and 0.29 ± 0.03 mL/min*g, respectively) compared to CON (65.06 ± 15.10 mL/min and 0.21 ± 0.03 mL/min*g, respectively) peri-pubertal bulls. TBF was positively correlated with SC (r = 0.59; P = 0.04) and TTW (r = 0.66; P = 0.02). Ambient temperature was positively correlated with testes temperature (r = 0.78; P &lt; 0.01). No other differences were identified (P &gt; 0.05). Limited alterations in testis physiology were observed in melatonin-supplemented bulls.

scholarly journals Modeling Lactation Curve in Primiparous Beef Cattle

2016 ◽  
Vol 8 (4) ◽  
pp. 116 ◽  
Author(s):  
Ana C. Espasandin ◽  
Verónica Gutierrez ◽  
Alberto Casal ◽  
Ana Graña ◽  
Oscar Bentancur ◽  
...  
Keyword(s):  
Beef Cattle ◽  
Milk Yield ◽  
Repeated Measures ◽  
Fixed Effects ◽  
Post Partum ◽  
Random Effect ◽  
Live Weight ◽  
Coefficients Of Variation ◽  
Lactation Curve ◽  
Milking Machine

<p>The work describes lactation curves and compares two methods to estimate milk yield (MY) in a grazing beef cattle herd of the EEBR Station-Udelar, Uruguay. Twenty-four Hereford, Angus and F1-crossbreed primiparous cows were used to estimate MY once a month, from birth to weaning, by weigh-suckle-weigh (WSW) technique and milking-machine (MM). Milk yield (MY), milk yield retained energy (ReMY), and calf weight were analyzed as repeated measures in a model including: sex of calves, month of lactation, cow and calf breed, milking method, estimation day (1 or 2), and post-partum days as fixed effects, and cow nested within breed as the random effect. The correlation analysis and the Gage r&amp;R coefficient (repeatability and reproducibility) between the two methods were used to study their associations. Lactation curves were compared (AICC and BIC) using Wood (1964), and Jenkins and Ferrel (1984) models. The MY estimated differed with the methodology being WSW higher than MM (P &lt; 0.001). The r&amp;R coefficient (0.83) suggest lower associations between WSW and MM, being 18% and 6% the coefficients of variation, respectively. Cow breed was not significant for MY. Calf live weight and ReMY were negatively associated (-0.52, P &lt; 0.0001). Based on variability observed, MM is more accurate to estimate MY and Wood curve the most adjusted to describe lactation in grazing beef cattle.</p>

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