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PubMed2002

Comparisons of Angus-, Braunvieh-, Chianina-, Hereford-, Gelbvieh-, Maine Anjou-, and Red Poll-sired cows for weight, weight adjusted for body condition score, height, and body condition score.

Data from Angus, Hereford, and top-cross cows (n = 641) from 2- to 8-yr-old daughters of seven breeds of sires included in Cycle II of the Germplasm Evaluation Program at the U.S. Meat Animal Research Center, comprising cow weight (CW, n = 15,698), height (CH, n = 15,676), and condition score (CS, n = 15,667), were used to estimate breed-group differences. Data were recorded in four seasons of each year (1975 to 1982). The mixed model included cow age, season of measurement, and their interactions, year of birth, pregnancy-lactation code (PL), and breed-group as fixed effects for CW and CS. Analyses of weight adjusted for condition score included CS as covariate. The model for CH excluded PL. Random effects were additive genetic and permanent environmental effects. Differences among breed-groups were significant for all traits at different ages and were maintained across ages, with few interchanges in ranking through maturity. Cows were ranked (by breed of sire) in the following order for weight: Red Poll (lightest), Hereford-Angus (reciprocal), Braunvieh, Gelbvieh, Maine Anjou, and Chianina (heaviest). In general, cows sired by breeds of British origin were lighter and shorter than those of continental origin. Differences in weight due to differences in condition seemed to be of small magnitude because making an adjustment for condition score did not affect rankings of breed groups across ages. Differences among breed groups for height were consistent with differences for weight. Cows from Chianina sires were taller than Hereford-Angus cows by 14 to 15 cm across ages. In this study, breed of sire effects were significantly different for the mature size of their daughters.

Age Factors↗
PubMed2002

Breed comparisons of Angus, Brahman, Hereford, Pinzgauer, Sahiwal, and Tarentaise for weight, weight adjusted for condition score, height, and body condition score.

Data from topcross cows (n = 468) from six breeds of sire (Angus, Brahman, Hereford, Pinzgauer, Sahiwal, Tarentaise) and two breeds of dam (Angus and Hereford) of Cycle III of the Germplasm Evaluation (GPE) program at the U.S. Meat Animal Research Center (MARC) comprising cow weight (CW, n = 9,012), height (CH, n = 9,010), and condition score (CS, n = 8,991) recorded in four seasons per year from 2 to 6 yr of age were used to estimate breed-group differences. The mixed models included cow age, season of measurement and their interactions, year of birth, pregnancy-lactation code (PL), and breed group as fixed effects for CW and CS. Analyses of weight adjusted for condition score included CS as a linear covariate. Model for CH excluded PL. Random effects were additive genetic and permanent environmental effects. Differences among breed-groups were significant for all traits for different ages and were maintained across ages, with few interchanges in ranking through maturity. Cows with Sahiwal sires were lightest (392 to 479 kg), whereas Hereford-Angus (HA) reciprocal-cross cows were shortest (119 to 123 cm) at each age. Cows with Brahman sires were heaviest and tallest among breed groups at all ages, exceeding HA cows by 19 to 24 kg and 9 to 10 cm, respectively. Cows with Pinzgauer and Tarentaise sires were intermediate for weight and height and interchanged ranking across ages. Differences in weight due to differences in condition seemed to be of small magnitude because adjustment for condition score did not affect rankings of breed groups across ages. Important changes for mature size of cows can be achieved by breed substitution with the breeds of sires used in this study.

Age Factors↗
PubMed2002

Heritability and correlations among body condition score loss, body condition score, production and reproductive performance.

The objectives of this study were to estimate the heritability of body condition score loss (BCSL) in early lactation and estimate genetic and phenotypic correlations among BCSL, body condition score (BCS), production, and reproductive performance. Body condition scores at calving and postpartum, mature equivalents for milk, fat and protein yield, days to first service, and services per conception were obtained from Dairy Records Management Systems in Raleigh, NC. Body condition score loss was defined as BCS at calving minus postpartum BCS. Heritabilities and correlations were estimated with a series of bivariate animal models with average-information REML. Herd-year-season effects and age at calving were included in all models. The length of the prior calving interval was included for all second lactation traits, and all nonproduction traits were analyzed with and without mature equivalent milk as a covariable. Initial correlations between BCS and BCSL were obtained using BCSL and BCS observations from the same cows. Additional genetic correlation estimates were generated through relationships between a group of cows with BCSL observations and a separate group of cows with BCS observations. Heritability estimates for BCSL ranged from 0.01 to 0.07. Genetic correlation estimates between BCSL and BCS at calving ranged from -0.15 to -0.26 in first lactation and from -0.11 to -0.48 in second lactation. Genetic correlation estimates between BCSL and postpartum BCS ranged from -0.70 to -0.99 in first lactation and from -0.56 to -0.91 in second lactation. Phenotypic correlation estimates between BCSL and BCS at calving were near 0.54, whereas phenotypic correlation estimates between BCSL and postpartum BCS were near -0.65. Genetic correlations between BCSL and yield traits ranged from 0.17 to 0.50. Genetic correlations between BCSL and days to first service ranged from 0.29 to 0.68. Selection for yield appears to increase BCSL by lowering postpartum BCS. More loss in BCS was associated with an increase in days to first service.

Animals↗
PubMed1976

[Individual conditions of pharmacogenic confusion conditions. Comparison of amitriptyline and clozapine].

The literature was surveyed concerning the frequency and conditions for confusional states and deliria following Amitriptyline and Clozapine treatment, and certain discrepancies were noted. As a result a retrospective comparative investigation was carried out as to the frequency and the conditions for such events in a group of patients treated along the same lines. While our experience with Amitriptyline is not different from that reported by others, this does not seem to be the case with Clozapine. Confusional states and deliria are four times as frequent as the average reported in the literature; it is clear that they depend on conditions different from those of confusional states and deliria due to Amitriptyline; there is a slightly significant (p less than 0.05) correlation between the appearance of confusion and a temperature of over 37.5 degrees C. The anticholinergic properties of Amitriptyline and of Clozapine cannot explain the difference in frequency, nor the differing conditions for the appearance, of pharmacogenic confusional states and deliria with those two substances.

Adult↗
PubMed1989

[Life conditions of families with children in the Municipality of Copenhagen. 2. Life conditions distributed in social districts].

As the basic knowledge for possible health planning in smaller districts, a description was made of the basic living conditions of families with children in Copenhagen and the utilization of public assistance and the employment of hospitalization of the children. These parameters are distributed among the 20 social districts in the municipality. The material concerning the more than 36,000 families was obtained by means of combination of data from registers concerning the population of Copenhagen. Four indicators were chosen for the living conditions of the families with children and by means of an additive index the social districts were ranged as good/poor as regards stressed families with children. Considerable variation was shown between the districts. A markedly positive connection was found between the living condition index of a district and cash public assistance. The living condition index was less clearly associated with the frequencies of hospitalization of the children. Utilization of existing registers in district planning is discussed.

Adolescent↗
PubMed1978

[The treatment of benign pathological conditions of the breasts with progesterone and progestogens. The results according to the type of breast condition (260 case records) (author's transl)].

This work reports the clinical results which were obtained after treating 260 women who had pathological conditions of the breasts using a combination of a progestogen which was given by a generalised route (orally or by injection) and progesterone which was applied locally so that its effect would be percutaneous on the breasts. These results were evaluated according to the effectiveness of the treatment according to the different symptoms or groups of clinical symptoms and radiological findings which had been noted at the time of the first examination. A better therapeutic effect was found in cases of early lesions where oedema was the dominant factor (mastodynia) and glandular hyperplasia (diffuse polyadenomatosis). On the other hand, longstanding lesions (sclerocystic mastopathia) where sclerosis was marked showed a much more variable result of treatment with progestogens. Therefore its seems that benign conditions of the breasts should be treated early and particularly in the stage of mastodynia if development into irreversible sclerotic conditions is to be avoided. It also has to be carried on for a long time, especially if there are other risk factors for cancer which are associated with conditions in the breast. The prophylactic role of this treatment in regard to cancer of the breast is discussed.

Adenofibroma↗
PubMed1989

Classical discrimination conditioning of the rabbit's eyelid response using pontine stimulation as a conditioned stimulus.

Classical discrimination conditioning of the nictitating membrane/eyelid response was performed on seven rabbits using stimulation of the pontine nuclei or middle cerebellar peduncle as the conditioned stimulus (CS) and an air puff as the unconditioned stimulus (US). The rabbits learned to discriminate between a CS paired with a US and delivered to one pontine nucleus (the CS+) and a CS presented alone and delivered to the contralateral pontine nucleus (the CS-). Subsequent reversal of the discrimination was also achieved when the CS+ and CS- stimulation sites were interchanged. The results are interpreted as support for the idea that essential plasticity for classical eyelid conditioning occurs efferent to the pontine nuclei, possibly in regions of the cerebellum.

Animals↗
PubMed2000

Spatial learning, contextual fear conditioning and conditioned emotional response in Fmr1 knockout mice.

Fmr1 knockout mice are an animal model for fragile X syndrome, the most common form of heritable mental retardation in humans. Fmr1 knockout mice exhibit macro-orchidism and cognitive and behavioural deficits reminiscent of the human phenotype. In the present study additional behavioural and cognitive testing was performed. Knockouts and control littermates were subjected to a spatial learning test using a plus-shaped water maze. Animals had to learn the position of a hidden escape platform during training trials. The position of this platform was changed during subsequent reversal trials. Previously reported deficits in reversal learning were replicated, but we also observed significant differences during the acquisition trials. A plus-shaped water maze experiment with daily changing platform positions failed to provide clear evidence for a working memory impairment, putatively underlying the spatial learning deficits. Two different test settings were used to examine the reported deficit of Fmr1 knockout mice in fear conditioning. Conditioned fear responses were observed in a contextual fear test, and the ability to acquire an emotional response was tested by means of response suppression in a conditioned emotional response procedure. Neither protocol revealed significant differences between controls and knockouts.

Acoustic Stimulation↗
PubMed1975

Effects of similarity of location and temporal intensity pattern of conditioned and unconditioned stimuli on the acquisition of conditioned suppresion in rats.

This article two studies that examined the effect of similarity of location and temporal intensity patterns of the conditioned stimulus (CS) and the unconditioned stimulus (UCS) on the acquision of conditioned suppression. Experiment 1 showed that greater suppression occurs during a stimulus generalization test when the tested stimulus has a location and temporal intensity pattern that is similar to the previously presented UCS. Experiment 2 showed that conditioned suppression is acquired more rapidly if the CS and UCS have similar locations and temporal intensity patterns. These similarity factors were interpreted as forms of event covariation, which aided in associative formation. Several applications of these data are discussed.

Animals↗
PubMed1991

Classical conditioning after temporal lobe lesions in man: impairment in conditional discrimination.

Left and right temporal lobectomy patients, patients with frontal lobe lesions, and healthy control subjects participated in an eyelid conditioning study based on conditional discrimination learning. All groups acquired the first conditioned response at a similar time during learning, but both temporal lobectomy groups showed poorer discrimination than control subjects. The results support models that relate hippocampal function to operation of if-then rules.

Adult↗
PubMed1992

Effects of amygdala lesions on reflex facilitation and conditioned response acquisition during nictitating membrane response conditioning in rabbit.

The present study demonstrated that large lesions of the amygdala disrupt the maintenance of reflex facilitation of the unconditioned nictitating membrane (NM) response and slow the acquisition of conditioned NM responses in rabbit. Before behavioral training, the central nucleus of the amygdala and adjacent areas were lesioned electrolytically. In the 1st experiment, the lesioned animals exhibited no reflex facilitation of the unconditioned NM response at conditioned stimulus (CS)-unconditioned stimulus (US) intervals of 125-8,000 ms. In the 2nd and 3rd experiments in which one CS-US interval (500 ms) was used, the lesions disrupted the maintenance of reflex facilitation but did not alter the facilitation exhibited in the 1st block of training. The lesions retarded the acquisition of conditioned NM responses when the 1000-Hz tone CS intensity was 65 dB but not when the intensity was 85 dB.

Acoustic Stimulation↗
PubMed1995

Conditioned diminution of the unconditioned response in rabbit eyeblink conditioning: identifying neural substrates in the cerebellum and brainstem.

Several models of Pavlovian conditioning assume that processing of an unconditioned stimulus (US) is diminished by a conditioned stimulus (CS) with which it had been paired. Two experiments evaluated the hypothesis that US processing may be diminished by CS-dependent activation of the cerebellum. Experiment 1 showed that electrical brain stimulation (EBS) of the cerebellar interpositus nucleus diminished the peak amplitude of the rabbit's unconditioned eyeblink response. This effect was bilateral, was systematically related to the intensity of EBS, maximal 50 ms after the offset of EBS, and substantially reversed by naloxone. Experiment 2 showed that inactivating the contralateral red nucleus with gamma-D-glutamylglycine blocked the decremental effect of interpositus stimulation. Implications for neural systems mediating the inhibitory effects of cerebellar activation and the antinociceptive role of noradrenergic and opioid systems in Pavlovian conditioning phenomena are discussed.

Animals↗
PubMed1997

Lesions of the mediodorsal nucleus of the thalamus and classical eyeblink conditioning under less-than-optimal stimulus conditions: role of partial reinforcement and interstimulus interval.

Rabbits received lesions of the mediodorsal nucleus of the thalamus (MD) or sham lesions and were subjected to classical eyeblink (EB) and heart rate (HR) conditioning. Separate groups of sham and lesioned animals received either 50% or 25% reinforcement with a periorbital shock unconditioned stimulus. Other groups received an interstimulus interval of either 1.0 or 1.5 s. Animals with MD lesions acquired the EB conditioned response (CR) more slowly than sham-lesioned animals with either the 1.5-s ISI or with the 25% reinforcement schedule. The lesions had no significant effect on the HR CR, however. Results suggest that information processed by MD is relayed to the prefrontal cortex and is required for somatomotor response selection under nonoptimal learning conditions.

Animals↗
PubMed2001

Eyeblink conditioning in the rabbit (Oryctolagus cuniculus) with stimulation of the mystacial vibrissae as a conditioned stimulus.

Eyeblink conditioning is a well-understood paradigm for the study of learning and memory and has been successfully employed with the use of auditory and visual conditioned stimuli (CSs). In this study, vibrotactile stimulation of the mystacial vibrissae was examined as an alternative CS in the rabbit (Oryctolagus cuniculus). The technique is described and acquisition of eyeblink conditioning (EBC) with stimulation of a single row of vibrissae in a delay paradigm is reported. Extinction of EBC with presentation of the CS alone is demonstrated, as well as reacquisition with stimulation of a single whisker. Finally, control experiments ensure that the CS has no auditory components. Ipsilateral presentation of the CS and airpuff is a more effective combination for training than contralateral presentations. Vibrotactile stimulation of the vibrissae as a CS will enable further examination of the neural correlates of learning in a well-characterized sensory system.

Animals↗
PubMed2001

Conditioned reinstatement of drug-seeking behavior with a discrete compound stimulus classically conditioned with intravenous cocaine.

The present study investigated the ability of a light and tone (LT) compound stimulus paired with cocaine infusions to reinstate cocaine-seeking behavior. Rats were trained to self-administer cocaine in the presence or absence of the LT during daily 3-hr sessions (maintenance). During Maintenance Days 5 and 10, rats underwent classical conditioning, whereby passive cocaine infusions were paired with either short-delayed, random, or no presentations of an LT. After extinction sessions, rats underwent test sessions in which the LT was presented in a noncontingent or response-contingent manner to measure conditioned cocaine-seeking behavior. The results demonstrated that response-contingent LT presentations significantly increased cocaine-seeking behavior and that the LT trained in a classical conditioning format transferred to an operant secondary reinforcer.

Animals↗
PubMed1982

Does conditioned nausea mediate drug-induced conditioned taste aversion?

Two antiemetic drugs were tested on the expression of taste aversions previously conditioned in rats with lithium, amphetamine or morphine. Neither prochlorperazine nor scopolamine administered prior to testing attenuated established aversions, although both drugs are known to have antiemetic effects in other species. Negative findings were obtained with a range of dose of prochlorperazine and scopolamine, with strong and weak aversions, with one- and two-stimulus tests, in a repeated one-stimulus extinction procedure, with between- and within-group designs and with hooded, albino, male and female rats. The results do not support the widely accepted hypothesis that conditioned nausea mediates conditioned taste aversion.

Amphetamine↗
PubMed1985

Influence of housing conditions and state of partner on conditioning and extinction of taste aversion to lithium and chlorpromazine.

Rats were used in two experiments to investigate the influence of social variables on the acquisition of Conditioned Taste Aversion (CTA) to either lithium chloride (10 ml/kg IP of a 0.3-M solution given twice) or chlorpromazine (8 mg/kg IP given four times) and on subsequent extinction. CTA acquisition was not affected by original housing assignment (isolation or paired housing for 15-23 days prior to conditioning), by the shifted social assignment during conditioning, or by the drugged state of the paired animals' partners on drug-scheduled days. However, for both drugs, permanently isolated animals extinguished CTA more slowly than rats housed permanently in pairs. Shifts from isolation to pairing or vice versa failed to alter CTA extinction in the case of lithium, but affected it significantly in chlorpromazine-treated rats. Shifts from isolation to paired housing with an undrugged partner produced faster extinction for lithium than the corresponding group with a drugged partner. For chlorpromazine, the effect of the same shift was exactly the opposite. Overall, the results show that changes in CTA extinction can be a function of social variables.

Animals↗
PubMed1992

Conditioned locomotor activity but not conditioned place preference following intra-accumbens infusions of cocaine.

In the first experiment, the conditioned place preference (CPP) paradigm was used to examine the rewarding properties of bilateral microinfusions of cocaine HCl into the nucleus accumbens (0, 12.5, 25, 50, or 100 micrograms). No dose of intra-accumbens cocaine induced a significant CPP. However, bilateral intra-accumbens infusions of d-amphetamine sulfate (10 micrograms) or intraperitoneal administration of cocaine HCl (5 or 10 mg/kg) both produced a significant preference for the drug-paired compartment. In the second experiment, the ability of bilateral intra-accumbens infusions of cocaine HCl (50 micrograms) to elicit conditioned locomotor activity (CLA) was examined. During the conditioning trials, intra-accumbens cocaine significantly increased locomotor activity. On the test day, when no drug was administered, the group that had previously received cocaine in the activity chamber showed significantly greater locomotor activity than the vehicle control group. This demonstration of CLA indicates that rats are able to associate the effects of intra-accumbens infusions of cocaine with environmental stimuli; however, these infusions are not rewarding as measured by the CPP paradigm. In addition, these results may indicate important differences between the neural substrates for cocaine and amphetamine reward and reveal a dissociation between CPP and CLA.

Amphetamine↗