Solar photo-Fenton and persulphate-based processes for landfill leachate treatment: A critical review.

Landfilling is the most usual solid waste management strategy for solid residues disposal. However, it entails several drawbacks such as the generation of landfill leachate that seriously threaten human life and the environment due to their toxicity and carcinogenic character. Among various technologies, solar photo-Fenton and sulphate-based processes have proven to be suitable for the treatment of these polluted streams. This review critically summarises the last three decades of studies in this field. It is found that the solar homogeneous photo-Fenton process should be preferably used as a pre- and post-treatment of biological technologies and as a standalone treatment for young, medium, and mature leachates, respectively. Studies on heterogeneous solar photo-Fenton process are lacking so that this technology may be scaled-up for industrial applications. Sulphate radicals are attractive for removing both COD and ammonia. However, no study has been reported on solar sulphate activation for landfill leachate treatment. This review discusses the main advances and challenges on treating landfill leachate through solar AOPs, it compares solar photo-Fenton and solar persulphate-based treatments, indicates the future research directions and contributes for a better understanding of these technologies towards sustainable treatment of landfill leachate in sunny and not-so-sunny regions.

Influence of Mechanical Cycling on Torque Values of Tapped-In and Screw-In Implant-Supported Crowns.

This study investigated the influence of mechanical cycling on screwed-in and tappedin implants restored with screw-retained metallic crowns. Three implant-abutmentcrown systems were evaluated: T1 (multi abutment) and T2 (standard abutment) received tapped-in abutments and S received a screwed-in abutment. The specimens were subjected to two million cycles of 0-150 N load, at 2 Hz, 30° inclination in a dry medium, and torque evaluation. Survival and removal torque were analyzed using chisquare, ANOVA, followed by Tukey's test. Differences between installation and removal torque were determined using a T-test for dependent samples. Analyses were performed in SPSS, considering α = 0.05. All specimens survived mechanical cycling in S, 40% in T1, 80% in T2 (p=0.008). Failures occurred due to loosening of the crown screw. A significant decrease in torque (p=0.000) was found. Group T1 had the lowest removal torque (1.6 ± 0.84 N.Cm²), followed by T2 (3 ± 1.49 N.Cm²) and S (6.3 ± 1.16 N. Cm²), and a statistical difference was found between Groups T1 and S. Both types of implantabutment connections were stable and can be considered for rehabilitative treatment, but failure and removal torque were influenced by the design of prosthetic abutment. Crowns were more susceptible to becoming loose in tapped-in systems.

Effect of organic compost and inorganic nitrogen fertigation on spinach growth, phytochemical accumulation and antioxidant activity.

The aim of this study was to evaluate the effect of the addition of organic compost in combination with the inorganic nitrogen fertigation on growth, phytochemical accumulation, and antioxidant activity of spinach (Spinacia oleracea L. cv. Manatee). Soil blocked spinach seedlings (six seedlings per block), three blocks per pot (316 plants m-2) were transplanted after 18 days after emergence into to 12 L pots. The treatments were: unfertilized soil, organic compost, organic compost +75 kg of N ha-1, applied as ammonium sulfate; and organic compost +75 kg N ha-1, applied as ammonium nitrate. The addition of organic compost to unfertilized soil increased the fresh yield. The application of inorganic N from the two sources in relation to organic compost treatment increased spinach fresh yield from 2.3 to 4.81 kg m-2 and shoot dry weight from 0.60 to 1,31 g plant-1. Levels of carotenoids also increased with inorganic N addition, producing higher values in plants grown with organic compost + ammonium nitrate (31.14 mg/100 g fresh weight). However, the addition of N led to a decrease in leaf-blade total phenols from 75 to 56 mg gallic acid equivalents/100mg fresh weight. The addition of inorganic N led to a dramatic decrease in leaf-blade ferric reducing antioxidant activity. This effect was higher with ammonium sulfate application. The application of organic compost and inorganic nitrogen had no influence on the petiole's phytochemical accumulation and antioxidant activity.

[Non-surgical treatment of Dupuytren's disease by using percutaneous needle aponeurotomy: A 10-year experience]. / Tratamiento no quirúrgico de la enfermedad de Dupuytren con aponeurotomía percutánea con aguja: 10 años de experiencia.

INTRODUCTION: Dupuytren's disease is a fibroproliferative disorder of the palmar aponeurosis that leads to digital flexion contractures. This disabling condition can be treated with a minimally invasive procedure, called percutaneous needle aponeurotomy (PNA). OBJECTIVE: To report the results of 10 years of experience treating Dupuytren's contracture by PNA in the rheumatology hand unit of our department. METHODS: We conducted a retrospective study with a description of method to perform PNA and analysis of post-procedure results. RESULTS: There were 197 patients with Dupuytren's disease. Ninety-eight patients (49.7%) underwent PNA, corresponding to 117 treated fingers. Good immediate results were achieved in 84% of the patients, with results being better in those with less advanced stages. Recurrences occurred in 12% of the patients. The complication rate was 1.7%. CONCLUSION: Our results confirm the value of this technique especially in the early stages of Dupuytren's disease, with immediate satisfactory results and a low rate of complications.

Plant growth, phytochemical accumulation and antioxidant activity of substrate-grown spinach.

Spinach production in soilless cultivation systems, mainly in substrate, transplanted with soil blocks and drip-irrigation is increasing worldwide. However, spinach establishment with soil blocks, with several seedlings per block compared with traditional planting methods, may affect light interception by plant canopy, wetting and salt patterns in root medium and therefore the plant growth and functional value of spinach. The effects of soil block number (plant density) and emitters spacing on plant growth, nitrate, proline and total phenols content and antioxidant activity were evaluated in spinach (Spinacia oleracea L). Five seedlings per soil block were transplanted to Styrofoam boxes filled with the substrate and grown during winter in an unheated greenhouse. Four treatments were carried out with two soil block numbers [8 (160 plants/m2) and 14 (280 plants/m2) soil blocks per Styrofoam box] and two emitter spacing [emitters spaced every 25 and 12.5 cm, respectively, with 4 and 8 emitters per Styrofoam box]. Neither plant density nor emitter spacing had any effect on shoot dry weight. Fresh yield increased as planting density and the number of emitters per Styrofoam box increased. The yield in Styrofoam boxes with 160 plants/m2 and 8 emitters (3.85 kg m-2) was ≈31 % lower than that obtained in treatment with 280 plants/m2 and 8 emitters (5.09 kg m-2). However, the leaf blade of the latter treatment presented a higher content of phenols and proline and greater antioxidant activity (FRAP and DPPH) as well as lower content of nitrate and lesser PDH activity. Decrease of space between emitters reduced the leaf blade nitrate concentration of spinach grown in a greenhouse during the winter. Leaf blade antioxidant activity (FRAP) decreased as planting density increased.

Synchronization treatments previous to natural breeding anticipate and improve the pregnancy rate of postpartum primiparous beef cows.

Timed AI has become a potential tool to bypass postpartum acyclicity, yet only a small percentage of the world bovine herd is inseminated. Most females are still subjected to bull mating; therefore, the frequent occurrence of postpartum anestrus may compromise their reproductive efficiency. Thus, the aim of this study was to develop an approach that allows the early conception of postpartum primiparous beef cows that are exposed to natural breeding (NB). For this purpose, 350 primiparous Nelore cows 35-65 d postpartum were allocated into three groups: Control (no hormonal treatment), TNB (hormonal protocol for timed-NB without equine chorionic gonadotropin; eCG) and TNB + eCG (hormonal protocol for TNB with eCG) groups. The protocol for TNB consisted of the insertion of a 1-g progesterone device and the intramuscular (IM) administration of 2 mg estradiol benzoate on D-9 (nine days before bull exposure), followed by device removal and the administration of 1 mg estradiol cypionate IM on D0. An additional 300 IU of eCG was given only to TNB + eCG cows. All cows were exposed to bull mating from D0 to D105. Pregnancy was checked by ultrasonography every 50 d, gestational age was estimated, and the number of new gestations every 21-d cycle (P21, P42, P63, P84 and P105) was predicted. Control cows had lower pregnancy at P21 (5.7%c, 7/123) than TNB (30.4%b, 35/115) and TNB + eCG (51.8%a, 58/112; P = 0.001) cows. Pregnancy rate increased across P42, P63 and P84 (P = 0.001) but remained higher for TNB + eCG cows. Regarding time to conception, the TNB + eCG cows achieved a greater than 50% pregnancy rate within the first days after bull exposure, while the TNB and Control cows took more than 40 d and 90 d to achieve 50% pregnancy rates, respectively. At the end of the breeding season (BS), TNB + eCG cows had a 21% higher pregnancy rate than the Control cows and a 16% higher rate than the TNB cows. The probability of conceiving increased 1.5-fold for cows treated with TNB (P = 0.0079) and 2.2-fold for cows additionally treated with eCG (P < 0.0001). The average interval between the onset of the BS and conception was reduced (P < 0.0001) for the TNB + eCG cows (26.5 ± 3.8c) compared to the TNB (35.7 ±â€¯4.1b) and Control (64.7 ±â€¯3.9a days) cows. Thus, the use of TNB, especially when associated with eCG, efficiently improved the early conception of postpartum primiparous beef cows after exposure to NB. The increased number of cows conceiving early in the BS is crucial to improve reproductive efficiency by reducing the interval between parturitions and improving the number of pregnant cows at the end of BS, thus resulting in greater farm income.

Review: Using artificial insemination v. natural service in beef herds.

The aim of this review is to compare the performance of different reproductive programs using natural service, estrus synchronization treatment before natural service (timed natural breeding (TNB)), artificial insemination (AI) following estrus detection and timed artificial insemination (TAI) in beef herds. It is well known that after parturition the beef cow undergoes a period of anestrous, when they do not exhibit estrus, eliminating the opportunity to become pregnant in the early postpartum by natural mating or by AI after detection of estrus. Hormonal stimulation is already a consistent and well-proven strategy used to overcome postpartum anestrus in beef herds. Basically, hormones that normally are produced during the estrous cycle of the cow can be administered in physiological doses to induce cyclicity and to precisely synchronize follicular growth, estrus and ovulation. Furthermore, two options of mating may be used after hormonal stimulation: natural service (i.e. utilization of bull service after synchronization, referred to as TNB) and TAI. These strategies improve the reproductive efficiency of the herds compared with natural service without estrus induction or synchronization. After the first synchronized service, the most common strategy adopted to get non-pregnant cows pregnant soon is the introduction of clean-up bulls until the end of the breeding season. However, methods to resynchronize non-pregnant cows after the first service are already well established and offer a potential tool to reduce the time for subsequent inseminations. Thus, the use of these technologies enable to eliminate the use of bulls by using resynchronization programs (i.e. two, three or four sequential TAI procedures). The dissemination of efficient reproductive procedures, such as TNB, TAI and Resynch programs, either isolated or in combination, enables the production of a greater quantity (obtaining increased pregnancy rates early in the breeding season) and quality (maximization of the use of AI with superior genetic sires) of beef calves. These technologies can contribute to improve the production efficiency, and consequently, improve livestock profitability.

Essential oils as antibacterial agents against food-borne pathogens: Are they really as useful as they are claimed to be?

Most studies evaluating the use of essential oils (EO) as antibacterial agents focus mainly on minimal inhibitory concentrations (MIC) rather than minimal bactericidal concentrations (MBC). In this work, we compared MICs and MBCs of EO from condiment plants commonly used in Mediterranean Europe, namely Origanum vulgare, Salvia lavandulaefolia, Salvia officinalis, Salvia sclarea and Rosmarinus officinalis, aiming to evaluate their application as disinfecting agents in minimally processed produce. Outbreaks-related pathogens such as Listeria monocytogenes, Pseudomonas aeruginosa and Yarrowia lipolytica were used. Results showed that all EO were able to reduce bacterial growth in all bacterial strains tested, particularly O. vulgare. However, fewer EO exhibited bactericidal activities, and were only effective against one or two bacterial strains, hence eliminating the possibility to use them as broad range disinfectants. Furthermore, the necessary concentrations were too high for food application. Hence, our work suggests the need to evaluate MBC rather than MIC and questions EO usefulness in controlling undesired microorganisms. Overall, and despite the large volume of data published on EO, results obtained were not very encouraging for a realistic application on produce and question the viability of EOs as disinfecting agents in food.

Low levels of exosomal-miRNAs in maternal blood are associated with early pregnancy loss in cloned cattle.

Nuclear reprogramming mediated by somatic cell nuclear transfer (SCNT) has many applications in medicine. However, animal clones show increased rates of abortion and reduced neonatal viability. Herein, we used exosomal-miRNA profiles as a non-invasive biomarker to identify pathological pregnancies. MiRNAs play important roles in cellular proliferation and differentiation during early mammalian development. Thus, the aim of this study was to identify exosomal-miRNAs in maternal blood at 21 days of gestation that could be used for diagnosis and prognosis during early clone pregnancies in cattle. Out of 40 bovine-specific miRNAs, 27 (67.5%) were with low abundance in the C-EPL (Clone - Early pregnancy loss) group compared with the C-LTP (Clone - Late pregnancy) and AI-LTP (Artificial Insemination - Late pregnancy) groups, which had similar miRNAs levels. Bioinformatics analysis of the predicted target genes demonstrated signaling pathways and functional annotation clusters associated with critical biological processes including cell proliferation, differentiation, apoptosis, angiogenesis and embryonic development. In conclusion, our results demonstrate decreased exosomal-miRNAs in maternal blood at 21 days of gestation in cloned cattle pregnancies that failed to reach term. Furthermore, the predicted target genes regulated by these 27 miRNAs are strongly associated with pregnancy establishment and in utero embryonic development.

A Xanthomonas citri subsp citri hypothetical protein related to virulence contains a non-functional HD domain and is implicated in flagellar motility.

Citrus canker, caused by the Gram-negative bacterium Xanthomonas citri subsp citri (Xac), severely affects most economically important citrus varieties worldwide. A previous study showed that disruption of the ORF XAC1201 from the Xac 306 strain by transposon Tn5 decreased bacterium virulence in the Rangpur lime host (Citrus limonia L. Osbeck). However, little is known regarding the possible function of the hypothetical protein XAC1201 and how it affects the virulence of Xac 306. Here, we confirmed that disruption of ORF XAC1201 reduces Xac 306 virulence in two different hosts, delaying the onset of typical symptoms. In silico analysis suggested that XAC1201 interacts with the flagellar proteins FliM and FliL, known to be an important factor for virulence. In fact, motility assays revealed that the XAC1201 mutant has a significant difference in motility compared to the wild-type Xac 306. Also, a 3-D structure model revealed modified cofactor binding sites and suggested that XAC1201 has a non-functional HD domain. This hypothesis was confirmed by enzymatic assays performed in purified, XAC1201 recombinant protein expressed in Escherichia coli, which revealed no significant activities previously associated with HD domains for the tested substrates. Thus, the role of the XAC1201 protein in Xac 306 virulence seems to be related to flagellar motility, although a non-classic role for the HD domain cannot be dismissed.

Inducing ovulation with oestradiol cypionate allows flexibility in the timing of insemination and removes the need for gonadotrophin-releasing hormone in timed AI protocols for dairy cows.

The effects of addition of gonadotrophin-releasing hormone (GnRH) to a progesterone plus oestradiol-based protocol and timing of insemination in Holstein cows treated for timed AI (TAI) were evaluated. Cows (n=481) received a progesterone device and 2mg oestradiol benzoate. After 8 days, the device was removed and 25mg dinoprost was administered. Cows were allocated to one of three (Study 1; n=57) or four (Study 2; n=424) groups, accordingly to ovulation inducer alone (Study 1; oestradiol cypionate (EC), GnRH or both) or ovulation inducer (EC alone or combined with GnRH) and timing of insemination (48 or 54h after device removal; Study 2). In Study 1, the diameter of the ovulatory follicle was greater for GnRH than EC. Oestrus and ovulation rates were similar regardless of ovulatory stimuli. However, time to ovulation was delayed when GnRH only was used. In Study 2, cows treated with GnRH or not had similar pregnancy per AI (P/AI) 30 days (41.5% vs 37.3%; P=0.28) and 60 days (35.9% vs 33.0%; P=0.61) after TAI. TAI 48 and 54h after device removal resulted similar P/AI at 30 days (40.3% vs 38.5%; P=0.63) and 60 days (33.8% vs 35.1%; P=0.72). Thus, adding GnRH at TAI does not improve pregnancy rates in dairy cows receiving EC. The flexibility of time to insemination enables TAI of a large number of cows using the same protocol and splitting the time of AI.

Modelling zinc changes at the hippocampal mossy fiber synaptic cleft.

Zinc, a transition metal existing in very high concentrations in the hippocampal mossy fibers from CA3 area, is assumed to be co-released with glutamate and to have a neuromodulatory role at the corresponding synapses. The synaptic action of zinc is determined both by the spatiotemporal characteristics of the zinc release process and by the kinetics of zinc binding to sites located in the cleft area, as well as by their concentrations. This work addresses total, free and complexed zinc concentration changes, in an individual synaptic cleft, following single, short and long periods of evoked zinc release. The results estimate the magnitude and time course of the concentrations of zinc complexes, assuming that the dynamics of the release processes are similar to those of glutamate. It is also considered that, for the cleft zinc concentrations used in the model (≤ 1 µM), there is no postsynaptic zinc entry. For this reason, all released zinc ends up being reuptaken in a process that is several orders of magnitude slower than that of release and has thus a much smaller amplitude. The time derivative of the total zinc concentration in the cleft is represented by the difference between two alpha functions, corresponding to the released and uptaken components. These include specific parameters that were chosen assuming zinc and glutamate co-release, with similar time courses. The peak amplitudes of free zinc in the cleft were selected based on previously reported experimental cleft zinc concentration changes evoked by single and multiple stimulation protocols. The results suggest that following a low amount of zinc release, similar to that associated with one or a few stimuli, zinc clearance is mainly mediated by zinc binding to the high-affinity sites on the NMDA receptors and to the low-affinity sites on the highly abundant GLAST glutamate transporters. In the case of higher zinc release brought about by a larger group of stimuli, most zinc binding occurs essentially to the GLAST transporters, having the corresponding zinc complex a maximum concentration that is more than one order of magnitude larger than that for the high and low affinity NMDA sites. The other zinc complexes considered in the model, namely those formed with sites on the AMPA receptors, calcium and KATP channels and with ATP molecules, have much smaller contributions to the synaptic zinc clearance.

Mapping and validation of Xanthomonas citri subsp citri genes regulated by putative plant-inducible promoter box (PIP-box).

Citrus canker, caused by the Gram-negative bacterium Xanthomonas citri subsp citri (Xac), is a major disease affecting citriculture worldwide, because of the susceptibility of the host and the lack of efficient control methods. Previous studies have reported that some genes of phytopathogenic bacteria possess a consensus nucleotide sequence (TTCGC...N15...TTCGC) designated the "plant-inducible-promoter box" (PIP box) located in the promoter region, which is responsible for activating the expression of pathogenicity and virulence factors when the pathogen is in contact with the host plant. In this study, we mapped and investigated the expression of 104 Xac genes associated with the PIP box sequences using a macroarray analysis. Xac gene expression was observed during in vitro (Xac grown for 12 or 20 h in XAM1 induction medium) or in vivo (bacteria grown in orange leaves for 3 to 5 days) infection conditions. Xac grown in non-induction NB liquid medium was used as the control. cDNA was isolated from bacteria grown under the different conditions and hybridized to the macroarray, and 32 genes differentially expressed during the infection period (in vitro or in vivo induction) were identified. The macroarray results were validated for some of the genes through semi-quantitative RT-PCR, and the functionality of the PIP box-containing promoter was demonstrated by activating b-glucuronidase reporter gene activity by the PIP box-containing promoter region during Xac-citrus host interaction.

Associations of insulin resistance later in lactation on fertility of dairy cows.

The challenge of getting dairy cows pregnant during early lactation is a well-described, worldwide problem. However, specifically in farms with poor reproductive, nutritional, and environmental conditions/management, a low pregnancy rate during early lactation is followed inevitably by an increased number of nonpregnant cows after 150 days in milk, with even more difficulties to achieve pregnancy. Therefore, several studies were designed to understand and develop strategies to mitigate reduced fertility of cows during late lactation. Experiments were performed under tropical regions to determine metabolic status during lactation and association of stage of lactation on oocyte quality and fertility. Lactating cows with extended days not pregnant (e.g.,>150 days in milk) often had systemic metabolic alterations, including development of peripheral insulin resistance and various oocyte alterations, including reduced expression of genes encoding glucose transport proteins, reduced amounts of mtDNA, increased expression of mitochondria-related genes, and increased expression of apoptosis-related genes. Additionally, in vitro embryo production and pregnancy per AI were lower in late- versus early-lactation cows in some but not all studies. Notwithstanding, when a normal embryo was transferred to a cow in late lactation, the pregnancy per transfer was reasonable, reinforcing the assertion that fertility problems in late-lactation cows may be associated with oocyte quality, fertilization, and/or failure of early embryo development. In conclusion, insulin resistance may reduce oocyte competence and consequently fertility in late-lactation dairy cows.

Legume seeds and colorectal cancer revisited: Protease inhibitors reduce MMP-9 activity and colon cancer cell migration.

MMP-9 activity is strongly related to cancer growth and metastization. This study aimed at assessing the inhibitory potential of the major seed protein fractions from eight selected legume species towards MMP-9 activity in colon carcinoma cells. Albumin and globulin fractions were screened for MMP-9 inhibitors, using a fluorometric assay and gelatin zymography. Their effect on HT29 cell proliferation and cell migration was tested, as well as on the corresponding intrinsic cellular MMP-9 activities. Seed proteins include potent inhibitors of MMP-9, particularly low molecular mass proteins. Their effectiveness differs greatly among species, with a positive correlation detected between their inhibitory activity and the reduction in cell migration. Lupin seeds contain the most efficient MMP-9 inhibitors of all legume seeds analyzed, inhibiting both gelatinases and HT29 migration and growth, while pea seeds showed no effect. Results reveal legume protein MMPIs as novel metalloproteinase inhibitors with possible pharmacological interest. This may be important for selecting leguminous species with potential use in anti-cancer diets.

Plasma anti-Müllerian hormone as a predictive endocrine marker to select Bos taurus (Holstein) and Bos indicus (Nelore) calves for in vitro embryo production.

This study evaluated the association between plasma anti-Müllerian hormone (AMH) concentrations and in vitro embryo production in Bos indicus (Nelore; experiment 1) and Bos taurus (Holstein; experiment 2) calves superstimulated or not with 140 mg of porcine follicle-stimulating hormone (pFSH; 4 decreasing doses twice daily). Oocytes were recovered from calves aged 2 to 4 mo after receiving gonadotropin stimulation (Nelore, n = 15; Holstein, n = 12) or not (Nelore, n = 15; Holstein, n = 12). Cycling heifers formed a positive control group (n = 15 for Nelore [aged 18-24 mo], n = 10 for Holstein [aged 14-16 mo]). All the calves underwent laparoscopic ovum pickup, and cycling heifers underwent a regular transvaginal ultrasound-guided ovum pickup for oocyte recovery. Immediately before oocyte retrieval, blood samples were taken for subsequent AMH determination (ng/mL). Regardless of the genetic group, calves that received pFSH (3.6 ± 1.1 in Nelore and 4.6 ± 1.2 in Holstein) or did not receive pFSH (3.2 ± 1.0 in Nelore and 2.5 ± 0.8 in Holstein) had greater plasma AMH concentrations (P = 0.01 in Nelore and P = 0.003 in Holstein) than cycling heifers (1.1 ± 0.2 in Nelore and 0.6 ± 0.07 in Holstein). AMH concentrations in calves with or without pFSH were similar in both genetic groups (3.6 ± 1.1 vs 3.2 ± 1.0 in Nelore; 4.6 ± 1.2 vs 2.5 ± 0.8 in Holstein). In calves, positive correlations were observed between plasma AMH concentrations and the numbers of follicles >2 mm (r = 0.86, P < 0.0001 in Nelore; r = 0.78, P < 0.0001 in Holstein), cumulus-oocyte complexes (COCs) retrieved (r = 0.91, P < 0.0001 in Nelore; r = 0.82, P < 0.0001 in Holstein), COCs cultured (r = 0.71, P < 0.0001 in Nelore; r = 0.79, P < 0.0001 in Holstein), and blastocysts produced (r = 0.62, P = 0.0003 in Nelore; r = 0.58, P = 0.009 in Holstein), and these results were independent of pFSH treatment. In conclusion, calves had greater plasma AMH concentrations than cycling heifers. In addition, treatment with pFSH did not influence AMH concentrations in calves, regardless of the genetic group. More importantly, plasma AMH concentrations were positively correlated with the antral follicle population and the number of COCs retrieved, COCs cultured, and blastocysts produced in B indicus and B taurus calves. Therefore, AMH is a promising tool for selecting oocyte donor calves to maximize results during in vitro embryo production.

Impact of progesterone and estradiol treatment before the onset of the breeding period on reproductive performance of Bos indicus beef heifers.

The present aimed to develop a hormonal therapy based on the insertion of a progesterone (P4) insert (PI) during 10 d plus an estradiol injection (E2) at PI removal before the onset of breeding of beef heifers. In Exp. 1, the plasma P4 profile of prepubertal heifers showed that the insertion of a PI or 24 d previously used P4 insert (UPI) sustained plasma P4 above 1 ng/mL for at least the first 7 d of the treatment. In Exp. 2 there was no positive effect of additional estradiol benzoate (EB) administered at the insertion of UPI on the proportion of heifers with a corpus luteum (CL/Treated) 30 d after UPI removal [UPI + EB = 85.3%(a) (n = 134); EB + UPI + EB = 80.8%(a) (n = 125)]; however, both were greater (P < 0.0001) than the Control group [60.3%(b) (n = 129)]. In Exp. 3, a positive effect (P=0.01) of UPI treatment and both E2 supplementations [EB and estradiol cypionate (EC); P = 0.10] at the UPI removal was observed on CL/Treated [Control = 42.5%(b) (n = 94); UPI = 58.5%(a) (n= 130); UPI + EB = 64.0%(a) (n = 128); UPI + EC = 67.2%(a) (n = 128)]. However, greater pregnancy per treated heifer (P/Treated) following artificial insemination (AI) upon estrus detection was achieved when EC was applied [Control = 20.2%(b); UPI = 29.2%(ab); UPI + EB = 26.6%(b); UPI + EC = 36.7%(a)]. In Exp. 4, the treatment prior to the timed AI (TAI) tended to improve pregnancy per TAI [P/AI; Control 43.6% (n = 298) vs. UPI+EC 51.9% (n = 342); P = 0.08], but increased P/Treated [26.5% vs. 43.3%; P < 0.001]. Thus, UPI + EC treatment were efficient in increasing the CL/Treated, tended to improve the P/AI and consequently enhanced P/Treated of zebu beef heifers.

Inferences of body energy reserves on conception rate of suckled Zebu beef cows subjected to timed artificial insemination followed by natural mating.

The influence of body condition score (BCS), rump fat thickness (RFAT), and live weight (LW), and the changes in these parameters during the interval from 165 of prepartum (i.e., 125 days of prior gestation) to 112 postpartum on first service conception and pregnancy rates were investigated in suckled Zebu (Bos indicus) beef cows (n = 266) subjected to timed artificial insemination (TAI) followed by natural mating. The aforementioned parameters were recorded at 165 ± 14 days (mean ± standard error) prepartum (concurrent with the weaning of previous calf), at parturition, and at 42 ± 7 days (at the onset of the synchronization of ovulation protocol), 82 ± 7 days (30 days after TAI), and 112 ± 7 days (60 days after TAI) postpartum. At the start of the breeding season (BS), cows were subjected to a synchronization of ovulation program for TAI. Bulls were placed with cows 10 days after TAI and remained until the end of the study (112 days postpartum). Cows with the highest BCS at parturition had an increased probability of first service conception rate at 60 days after TAI (P = 0.02) and a reduced probability of occurrence of pregnancy loss (P = 0.05). Also, cows had a greater likelihood of conceiving postpartum if they had greater RFAT and BCS at 165 ± 14 days prepartum (P = 0.01 and P = 0.03, respectively) and at parturition (P = 0.0007 and P = 0.003, respectively). Cows that had an increase in RFAT and BCS during the dry period (i.e., interval from weaning of the previous calf to parturition) also had a greater likelihood of conceiving (P = 0.03 and P = 0.06, respectively) during the BS. Among the different time points, RFAT and BCS at parturition had the largest impact on risk of conception during the BS. The LW was a poor predictor of conception during the BS (P = 0.11-0.68) except for LW at 165 ± 14 days prepartum (P = 0.01). Collectively, the findings indicated that the likelihood of conception during the BS was highest in cows that had an improvement in RFAT and BCS during the dry period. Therefore, assuring a good nutritional status in the dry period (BCS ≥ 3.0 at 165 ± 14 days prepartum and ≥3.25 at parturition) is an important aim to optimize the postpartum conception rate of suckled Zebu beef cows subjected to TAI followed by natural mating.

Effect of different doses of equine chorionic gonadotropin on follicular and luteal dynamics and P/AI of high-producing Holstein cows.

The hypotheses of this study were (1) that the administration of 400IU eCG in a TAI protocol would increase ovarian follicular growth and diameter of the largest follicle (LF), volume of the CL, and produce an earlier rise on serum concentration of progesterone (P4) to ultimately improve P/AI compared to non-treated high-producing Holstein cows; and (2) that 600IU of eCG could enhance any potential effects of a greater gonadotropin treatment upon follicular and luteal size and function, improving P/AI. Cows were subjected to a protocol of synchronization of ovulation for timed artificial insemination (TAI): D0-P4 device insert and estradiol benzoate, D8-P4 device removal and PGF2α; Experiment 1, D10PM - GnRH plus TAI; and Experiment 2, D10AM - GnRH, D10PM - TAI. In Experiment 1, at P4 device removal, cows were assigned to one of the two treatments to receive none (n=232) or 400IU (n=232) of eCG. In Experiment 2, again at P4 device removal, cows were assigned to one of the three treatments to receive no eCG, (n=166) 400 (n=145) or 600IU (n=145) of eCG. Pregnancy was diagnosed 35 days after TAI. Ultrasonographic examination of both ovaries was done in a subset of cows in Experiments 1 [no eCG (n=27) and 400IU eCG (n=14)], and 2 [no eCG (n=15), 400IU eCG (n=14) and 600IU eCG (n=11)]. Exams were conducted at device removal (D8) and TAI (D10) to measure the diameter of the LF; then twice daily from D10 to 13, to determine time to ovulation and the maximum diameter of the LF; and then 3 (D14), 6 (D17), 9 (D20) and 12 (D23) days after presumed ovulation, concurrent with blood sampling, to measure the volume of the CL and serum concentration of P4. In both studies, eCG (400 or 600IU)-treated cows had similar diameter of the LF on D8 and D10, growth rate of the LF from Days 8 to 10, ovulation rate, time to ovulation, volume of the CL, serum concentration of P4 and P/AI as compared to control animals. Thus, adding either 400 or 600IU eCG to TAI protocols was inefficient to alter follicular and luteal dynamics and increase P/AI in high-producing dairy cows under the conditions of these experiments. The lack of positive effects of eCG in the present study might be explained by the small percentage of cows with poor body condition score and lesser incidence of anestrus.