271 Assessment of Efficacy of Deworming Options in Recently Weaned Beef Cattle Utilizing Different Anthelmintic Programs in the Southeast

This experiment measured the effect of three different deworming strategies on animal performance and Egg per gram (EPG) reduction during a pre-conditioning phase of beef calves using a completely random block designed with n = 797 calves (Year 1 = 263 ± 39 kg; Year 2 = 257 ± 37 kg) randomly assigned to one of four treatments: orally suspended oxfendazole (1ml/55 kgs; ORAL), transdermal eprinomectin (1ml/10 kgs; POUR), both anthelmintic (BOTH), and no treatment (CONT). Weaned calves at four University of Georgia research stations (Calhoun, Alapaha, Eatonton, JPC) were blocked by weight, age, and sex. Calves were weighed at weaning prior to treatment d 0 and on d 42. Fecal samples were collected on d 0 and d 14 from 40 calves per treatment. Anthelmintic resistance was determined if percent EPG reduction and Upper 95% confidence limit were below 95% and the lower 95% confidence limit were below 90%. The ADG was lowest (P < 0.001) for CONT (0.262 kg/d) compared to POUR, ORAL, and BOTH (0.370, 0.412, and 0.387 kg/d, respectively) Anthelmintic resistance to POUR was detected at Eatonton and Alapaha (47.4% and 15.4% reduction respectively), and deemed inconclusive at JPC and Calhoun (51.1% and 50.3% reduction respectively). Only ORAL and BOTH effectively reduced EPG counts across all four research units (> 97.9% reduction). While the POUR option improved animal performance, it was not effective at reducing EPG within the herd. This study demonstrated that the ORAL and BOTH treatments increased ADG compared to CONT and were effective at reducing EPG counts; however, BOTH costs, on average, $3.00 more than ORAL. Producers must consider the cost of each option when choosing a deworming strategy. Based on these results, using orally suspended oxfendazole is a more economical, and effective options to treat parasites during a pre-conditioning phase.

Differential effects of intra-modal and cross-modal reward value on visual perception: ERP evidence

Stimuli associated with high reward modulate perception and such value-driven effects have been shown to originate from the modulation of the earliest stages of sensory processing in the brain. In natural environments objects comprise multiple features (imagine a rolling soccer ball, with its black and white patches and the swishing sound made during its motion), where each feature may signal different associations with previously encountered rewards. How perception of such an object is affected by the value associations of its constituent parts is unknown. The present study compares intra- and cross-modal value-driven effects on behavioral and electrophysiological correlates of visual perception. Human participants first learned the reward associations of visual and auditory cues. Subsequently, they performed a visual orientation discrimination task in the presence of previously rewarded visual or auditory cues (intra- and cross-modal cues, respectively) that were concurrently presented with the target stimulus. During the conditioning phase, when reward associations were learned and reward cues were the target of the task, reward value of both modalities enhanced the electrophysiological correlates of sensory processing in visual cortex. During the post-conditioning phase, when reward delivery was halted and previously rewarded stimuli were task-irrelevant, cross-modal value-enhanced behavioral measures of visual sensitivity whereas intra-modal value led to a trend for suppression. A similar pattern of modulations was found in the simultaneously recorded event-related potentials (ERPs) of posterior electrodes. We found an early (90-120 ms) suppression of ERPs evoked by high-value, intra-modal stimuli. Cross-modal cues led to a later value-driven modulation, with an enhancement of response positivity for high- compared to low-value stimuli starting at the N1 window (180-250 ms) and extending to the P3 (300-600 ms) responses of the posterior electrodes. These results indicate that visual cortex is modulated by the reward value of visual as well as auditory cues. Previously rewarded, task-irrelevant cues from the same or different sensory modality have a different effect on visual perception, as intra-modal high-value cues may interfere with the target processing, whereas cross-modal high-value cues boost the perception of the target.

Contrasting Effects of Plant-Soil Feedbacks on Growth and Morphology of Two Clonal Plants

AimSoil abiotic and biotic conditions are often spatially variable, challenging plants with a heterogeneous environment consisting of favorable and unfavorable patches of soil. Many stoloniferous clonal plants can escape from unfavorable patches by elongating stolon internodes, but aggregate in favorable ones through shortening stolon internodes. However, whether these plants can use their stolons to respond to plant-soil feedbacks (PSFs) is largely unknown. MethodsIn the conditioning phase, we grew either Hydrocotyle vulgaris or Glechoma longituba clonal plants separately in mesocosms to condition bulk soil. In the feedback phase, we grew connected mother and daughter ramets of each species in soil inoculated with the unsterilized or sterilized soil conditioned by conspecifics. We grew the plants for 12 weeks and measured the growth of the mother and daughter ramets separately. ResultsThe daughter ramets of H. vulgaris produced more biomass but shorter stolon internodes when grown in soil with sterilized inocula than with unsterilized inocula. However, no difference was found between the daughter ramets of G. longituba grown in soil with unsterilized and sterilized inocula. For both species, no significant difference was found between the mother ramet or between the daughter ramets when the mother ramet was grown in soil with sterilized and unsterilized inocula. ConclusionsThe daughter ramets rather than the mother ramet of H. vulgaris experienced negative biotic PSFs. However, PSF had no effects on the daughter or mother ramet of G. longituba. Moreover, physiological integration or plasticity in stolon internode lengths cannot help H. vulgaris alleviate the negative PSFs.

Volume Reduction: Which Dose is Sufficient to Retain Resistance Training Adaptations in Older Women?

We compared the effects of different resistance training (RT) volume reduction strategies on muscular strength and lean soft-tissue (LST) in older women. Fifty-seven physically independent women (>60 years) performed a 20-week pre-conditioning phase of a standardized whole-body RT program (eight exercises, three sets, 8–12 repetitions, three sessions a week), and were then randomly assigned to one of the following conditions: reduced volume for a single set (RV1, n=20) or two sets (RV2, n=19), or maintained volume of three sets (MV, n=18) for 8 weeks (specific training phase). Muscular strength in the chest press, leg extension, and preacher curl exercises was determined by one-repetition maximum tests. A dual-energy X-ray absorptiometry device was used to estimate LST. An increase in muscular strength (16.3–32.1%) and LST (3.2–7.9%) was observed after the pre-conditioning phase. There was an increase in chest press for all groups (9.4–16.7%) after the specific training phase. In contrast, only MV increased significantly in the leg extension (4.4%). No between-group differences were revealed for LST in the specific training phase. Our results suggest that reduced RT volume from three to one set per exercise for 8 weeks seems sufficient to retain neuromuscular adaptations in older women.

Involvement of the dopaminergic system in the reward-related behavior of pregabalin

There has been an increase in cases of drug addiction and prescription drug abuse worldwide. Recently, pregabalin abuse has been a focus for many healthcare agencies, as highlighted by epidemiological studies. We previously evaluated the possibility of pregabalin abuse using the conditioned place preference (CPP) paradigm. We observed that a 60 mg/kg dose could induce CPP in mice and that pregabalin-rewarding properties were mediated through glutamate neurotransmission. Notably, the dopaminergic reward circuitry is also known to play a crucial role in medication-seeking behavior. Therefore, this study aimed to explore the possible involvement of dopaminergic receptor-1 in pregabalin-induced CPP. Mice were randomly allocated to receive saline or the dopamine-1 receptor antagonist SKF-83566 (0.03 mg/kg, intraperitoneal). After 30 min, the mice received either saline or pregabalin (60 mg/kg) during the conditioning phase. Among the control groups that received saline or SKF-83566, the time spent in the two conditioning chambers was not significantly altered. However, among the pregabalin-treated group, there was a marked increase in the time spent in the drug-paired chamber compared to the time spent in the vehicle-paired chamber. Notably, blocking dopamine-1 receptors with SKF-83566 completely prevented pregabalin-induced place preference, thus demonstrating the engagement of the dopaminergic system in pregabalin-induced reward-related behavior.

Direct Biotic Plant–soil Feedback Promotes Dodonaea Viscosa Growth in a Dry-hot Valley, China

Biotic plant-soil feedback has been widely studied, and may be particularly important in resource-poor areas. However, the roles of soil nutrient cycling in affecting plant growth in this process still remained unclear. The aim of this study was to explore the roles of soil biota in regulating nutrient cycling by conducting a two-phase feedback experiment in a dry-hot valley, with a conditioning phase during which there were Dodonaea viscosa or no D. viscosa growing in the soil, and a feedback phase in which the effect of the conditioned soil biota on D. viscosa performance was measured. The growth of D. viscosa significantly reduced soil N after the conditioning phase. However, D. viscosa showed a positive plant-soil feedback. In the feedback phase, the D. viscosa conditioned soil promoted the stem diameter, leaf area, and leaf dry mass content of D. viscosa. Total biomass was also significantly higher in D. viscosa conditioned soil than that in not conditioned soil. In contrast, soil sterilization had a negative effect on the growth of D. viscosa, with a significant reduction in plant biomass, especially in D. viscosa conditioned soil, and soil sterilization significantly increased the root: shoot biomass ratio and litter mass. Furthermore, we showed that although the biota-driven changes in enzyme activities correlated with the leaf N and P amount especially P amount, the enzyme activity was not the main reason to promote D. viscosa growth in the conditioned soil.

Quetiapine-Induced Place Preference in Mice: Possible Dopaminergic Pathway

Quetiapine, an atypical antipsychotic, is effective in the management of schizophrenia, depression, and anxiety. Although quetiapine overdosage and misuse have been reported, its abuse potential has not been investigated in animals. In this study, the abuse potential of quetiapine was assessed based on the conditioned place preference (CPP) paradigm of drug addiction in a mouse model. First, mice received intraperitoneal injections of quetiapine (40, 80, or 120 mg/kg) every other day during the conditioning phase. In the second experiment, mice were pretreated with 0.03 mg/kg SKF-35866, a D1 receptor antagonist, before receiving saline or quetiapine (120 mg/kg) during the conditioning phase. No significant changes in time spent in the quetiapine-paired chamber were observed compared with time spent in the saline-paired chamber in mice treated with 40 or 80 mg/kg. In contrast, the preference to the quetiapine-paired chamber was significantly increased in mice treated with 120 mg/kg quetiapine, and this effect was blocked by SKF-35866 pretreatment. These results demonstrated, for the first time, the abuse potential of quetiapine in an animal model of drug addiction. Interestingly, this CPP-inducing effect was likely mediated by activating D1 receptors.

Concurrent Electrodermal and Eyeblink Conditioning With Masked and Unmasked Stimuli

The aim of this study was to determine if contingency awareness between the conditioned (CS) and unconditioned stimulus (US) is necessary for concurrent electrodermal and eyeblink conditioning to masked stimuli. An angry woman’s face (CS+) and a fearful face (CS−) were presented for 23 milliseconds (ms) and followed by a neutral face as a mask. A 98 dB noise burst (US) was administered 477 ms after CS+ offset to elicit both electrodermal and eyeblink responses. For the unmasking conditioning a 176 ms blank screen was inserted between the CS and the mask. Contingency awareness was assessed using trial-by-trial ratings of US-expectancy in a post-conditioning phase. The results showed acquisition of differential electrodermal and eyeblink conditioning in aware, but not in unaware participants. Acquisition of differential eyeblink conditioning required more trials than electrodermal conditioning. These results provided strong evidence of the causal role of contingency awareness on differential eyeblink and electrodermal conditioning.

Changes in c-fos and p-CREB signaling following exposure to forced swim stress or exogenous corticosterone during morphine-induced place preference are dependent on glucocorticoid receptor in the basolateral amygdala

Neural circuitry comprising the nucleus accumbens (NAc), prefrontal cortex (PFC), amygdala (AMY), and hippocampus (HIP) are the main components of the reward circuit. Our previous behavioral data showed that forced swim stress (FSS) and corticosterone administration could inhibit the acquisition of morphine-induced conditioned place preference (CPP), and this effect was blocked by intra-basolateral amygdala (BLA) administration of RU38486, glucocorticoid receptor (GR) antagonist. Therefore, we tried to evaluate the effect of intra-BLA administration of the GR antagonist during the conditioning phase on the c-fos and p-CREB/CREB ratio expression in the AMY, NAc, PFC, and HIP of rats that underwent FSS or received exogenous corticosterone (10 mg/kg; i.p.) before morphine injection (5 mg/kg; s.c.) during 3 conditioning days. Our results showed that morphine-induced CPP could increase c-fos level and p-CREB/CREB ratio in all regions (except in the HIP). In addition, c-fos expression was elevated by FSS in all regions and blockade of GR decreased this effect. In the PFC, in addition to FSS, corticosterone could raise c-fos expression, which was blocked by RU38486. In conclusion, it seems that the intra-BLA administration of RU38486 differently modulates the effect of morphine-induced CPP on the expression of c-fos and p-CREB/CREB ratio in animals that underwent FSS or corticosterone administration.

Intolerance of uncertainty and threat reversal: A conceptual replication of Morriss et al. (2019)

The ability to update responding to threat cues is an important adaptive ability. Recently, Morriss and colleagues (2019) demonstrated that participants scoring high in Intolerance of Uncertainty (IU) were more capable of threat reversal. The current report aimed to conceptually replicate these results of Morriss et al. (2019) in an independent sample using a comparable paradigm (n = 102). Following a threat conditioning phase, participants were told that cues associated with threat and safety from electric shock would reverse. Responding was measured with skin conductance and fear potentiated startle. We failed to replicate the results of Morriss et al., (2019). Instead, we found that individuals with lower IU, relative to higher IU, who received contingency instructions prior to acquisition were more capable of threat reversal, indexed via skin conductance response. These results suggest that IU and contingency instructions differentially modulate the course of threat reversal.