Polycyclic aromatic hydrocarbons in a polyherbal drug: human health exposure-associated risk assessment study.

PAHs are pervasive pollutants known to bioaccumulate in environmental matrices, plants, and humans. Dr. Iguedo Goko Cleanser® is a polyherbal drug with unsubstantiated claims to treat various diseases in sub-Saharan Africa. PAHs were measured following EPA-16 PAHs guidelines using Gas Chromatography (Agilent-6890N, USA). The drug's exposure-associated public health concerns was determined using suitable mathematical paradigms. PAHs present were acenaphthene (2.74 × 10-2), pyrene (2.7598 × 10-2), and chrysene (5.1277 × 10-2) ppm. Dietary intake of chrysene, acenaphthene and pyrene for adults, and children ranged from 2.466-4.615 × 10-3 and 1.215-2.308 × 10-3 ppm/mg/kg, respectively. B[α]Peq, EDB[α]Peq, and incremental lifetime cancer risk were determined to be 5.6777 × 10-4, 5.109912 × 10-5 and 5.3289 × 10-12, respectively. Our results suggest a high risk of non-carcinogenic adverse health effects, especially on chronic exposure among adolescents and adults, necessitating caution and/or avoidance of its chronic use. Therefore, policy formulation and implementation as regards the safety of plant-based remedies and allied products before their distribution among end-users must be ensured.

Gender differences in tuberculosis treatment outcomes: a post hoc analysis of the REMoxTB study.

BACKGROUND: In the REMoxTB study of 4-month treatment-shortening regimens containing moxifloxacin compared to the standard 6-month regimen for tuberculosis, the proportion of unfavourable outcomes for women was similar in all study arms, but men had more frequent unfavourable outcomes (bacteriologically or clinically defined failure or relapse within 18 months after randomisation) on the shortened moxifloxacin-containing regimens. The reason for this gender disparity in treatment outcome is poorly understood. METHODS: The gender differences in baseline variables were calculated, as was time to smear and culture conversion and Kaplan-Meier plots were constructed. In post hoc exploratory analyses, multivariable logistic regression modelling and an observed case analysis were used to explore factors associated with both gender and unfavourable treatment outcome. RESULTS: The per-protocol population included 472/1548 (30%) women. Women were younger and had lower rates of cavitation, smoking and weight (all p < 0.05) and higher prevalence of HIV (10% vs 6%, p = 0.001). They received higher doses (mg/kg) than men of rifampicin, isoniazid, pyrazinamide and moxifloxacin (p ≤ 0.005). There was no difference in baseline smear grading or mycobacterial growth indicator tube (MGIT) time to positivity. Women converted to negative cultures more quickly than men on Lowenstein-Jensen (HR 1.14, p = 0.008) and MGIT media (HR 1.19, p < 0.001). In men, the presence of cavitation, positive HIV status, higher age, lower BMI and 'ever smoked' were independently associated with unfavourable treatment outcome. In women, only 'ever smoked' was independently associated with unfavourable treatment outcome. Only for cavitation was there a gender difference in treatment outcomes by regimen; their outcome in the 4-month arms was significantly poorer compared to the 6-month treatment arm (p < 0.001). Women, with or without cavities, and men without cavities had a similar outcome on all treatment arms (p = 0.218, 0.224 and 0.689 respectively). For all other covariate subgroups, there were no differences in treatment effects for men or women. CONCLUSIONS: Gender differences in TB treatment responses for the shorter regimens in the REMoxTB study may be explained by poor outcomes in men with cavitation on the moxifloxacin-containing regimens. We observed that women with cavities, or without, on the 4-month moxifloxacin regimens had similar outcomes to all patients on the standard 6-month treatment. The biological reasons for this difference are poorly understood and require further exploration.

Proportion of Tubal Factor Infertility due to Chlamydia: Finite Mixture Modeling of Serum Antibody Titers.

In this study, we examined whether the proportion of tubal factor infertility (TFI) that is attributable to Chlamydia trachomatis, the population excess fraction (PEF), can be estimated from serological data using finite mixture modeling. Whole-cell inclusion immunofluorescence serum antibody titers were recorded among infertile women seen at St. Michael's Hospital in Bristol, United Kingdom, during the period 1985-1995. Women were classified as TFI cases or controls based on laparoscopic examination. Finite mixture models were used to identify the number of component titer distributions and the proportion of serum samples in each, from which estimates of PEF were derived. Four titer distributions were identified. The component at the highest titer was found only in samples from women with TFI, but there was also an excess of the second-highest titer component in TFI cases. Minimum and maximum estimates of the PEF were 28.0% (95% credible interval: 6.9, 50.0) and 46.8% (95% credible interval: 23.2, 64.1). Equivalent estimates based on the standard PEF formula from case-control studies were 0% and over 65%. Finite mixture modeling can be applied to serological data to obtain estimates of the proportion of reproductive damage attributable to C. trachomatis Further studies using modern assays in contemporary, representative populations should be undertaken.

Pretomanid with bedaquiline and linezolid for drug-resistant TB: a comparison of prospective cohorts.

BACKGROUND: There are no data comparing the 6-9 month oral three-drug Nix regimen (bedaquiline, pretomanid and linezolid [BPaL]) to conventional regimens containing bedaquiline (B, BDQ) and linezolid (L, LZD).METHODS: Six-month post end-of-treatment outcomes were compared between Nix-TB (n = 109) and 102 prospectively recruited extensively drug-resistant TB patients who received an ˜18-month BDQ-based regimen (median of 8 drugs). A subset of patients received BDQ and LZD (n = 86), and a subgroup of these (n = 75) served as individually matched controls in a pairwise comparison to determine differences in regimen efficacy.RESULTS: Favourable outcomes (%) were significantly better with BPaL than with the B-L-based combination regimen (98/109, 89.9% vs. 56/86, 65.1%; adjusted relative risk ratio [aRRR] 1.35; P < 0.001) and in the matched pairwise analysis (67/75, 89.3% vs. 48/75, 64.0%; aRRR 1.39; P = 0.001), despite significantly higher baseline bacterial load and prior second-line drug exposure in the BPaL cohort. Time to culture conversion (P < 0.001), time to unfavourable outcome (P < 0.01) and time to death (P < 0.03) were significantly better or lower with BPaL than the B-L-based combinations.CONCLUSION: The BPaL regimen (and hence substitution of multiple other drugs by pretomanid and/or higher starting-dose LZD) may improve outcomes in drug-resistant TB patients with poor prognostic features. However, prospective controlled studies are required to definitively answer this question.

A partially randomised trial of pretomanid, moxifloxacin and pyrazinamide for pulmonary TB.

BACKGROUND: Treatment for TB is lengthy and toxic, and new regimens are needed.METHODS: Participants with pulmonary drug-susceptible TB (DS-TB) were randomised to receive: 200 mg pretomanid (Pa, PMD) daily, 400 mg moxifloxacin (M) and 1500 mg pyrazinamide (Z) for 6 months (6Pa200MZ) or 4 months (4Pa200MZ); 100 mg pretomanid daily for 4 months in the same combination (4Pa100MZ); or standard DS-TB treatment for 6 months. The primary outcome was treatment failure or relapse at 12 months post-randomisation. The non-inferiority margin for between-group differences was 12.0%. Recruitment was paused following three deaths and not resumed.RESULTS: Respectively 4/47 (8.5%), 11/57 (19.3%), 14/52 (26.9%) and 1/53 (1.9%) DS-TB outcomes were unfavourable in patients on 6Pa200MZ, 4Pa200MZ, 4Pa100MZ and controls. There was a 6.6% (95% CI -2.2% to 15.4%) difference per protocol and 9.9% (95%CI -4.1% to 23.9%) modified intention-to-treat difference in unfavourable responses between the control and 6Pa200MZ arms. Grade 3+ adverse events affected 68/203 (33.5%) receiving experimental regimens, and 19/68 (27.9%) on control. Ten of 203 (4.9%) participants on experimental arms and 2/68 (2.9%) controls died.CONCLUSION: PaMZ regimens did not achieve non-inferiority in this under-powered trial. An ongoing evaluation of PMD remains a priority.

Social interactions among rodent conspecifics: a review of experimental paradigms.

The authors suggest that kin selection theory offers a different perspective from which to examine social interactions among rodent conspecifics. Paradigms designed to investigate various interactions among rodent conspecifics are presented, and include simple affiliative behaviors, social facilitation, and cooperation. It is established that many species of rodents are appropriately social to use as subjects under investigation in research which focuses on topics such as kin selection. Studies reporting positive results as well as some reporting negative or inconclusive results have been presented for the purpose of informing the reader under which conditions we might expect specific social behaviors to occur. It is concluded that a combined method of a sociobiological perspective using established experimental procedures will offer unique opportunities for the investigation of specific predictions suggested by kin selection theory.

Serum C reactive protein in infective endocarditis.

C reactive protein (CRP) was measured serially in 29 patients with infective endocarditis. Twenty one patients were initially treated with antimicrobial drugs. In 13, serial measurement of CRP concentrations showed a progressive return to normal (less than 10 mg/l), which correlated with a satisfactory recovery. Of the remainder (eight patients), five had persistently high concentrations of CRP, indicating a failure to respond to antimicrobial treatment alone. Two of these five patients died and three underwent valve replacement. Of 11 patients treated with antibiotics and valve replacement, CRP concentrations returned to normal in nine. Two patients had infective complications and the CRP concentration did not return to normal. A transient rise in CRP concentration during an otherwise uneventful fall to normal was a sign of allergic reaction in two and of intercurrent infection in three more patients. Serial measurements of CRP concentrations in patients with infective endocarditis may be useful to monitor treatment and also to detect other infections and complications.

Patient reactions to met and unmet psychological need: a critical incident analysis.

Patients with cancer must deal with a variety of psychological and social difficulties, but the extent to which staff assist patients with these difficulties is not clear. Using the Critical Incident Technique (CIT), patients attending a Cancer Centre were asked to describe situations in which their emotional needs were, and were not, met by staff. Although most patients were able to describe a situation in which their needs were met by staff, 23% also described a situation in which this was not the case. These latter incidents were often related to anxiety, confusion and a wish to sever links with the hospital. Patients who reported that their needs were not met requested more staff time and further information about their diagnosis and treatment.

Biological responses to the reversal of acidification in surface waters of the English Lake District.

Declining sulphur deposition since the late 1970s has led to increases in pH in lakes and streams of the English Lake District (Cumbria, UK). To determine whether there have been biological responses to the chemical changes, we carried out surveys of stream macroinvertebrates and lake surface sediment diatoms, and compared the results with those from earlier surveys. Macroinvertebrate taxa in five streams (current average pH range 5.1-7.0) sampled in 1999 showed clear changes from those found during 1965/1966 and 1972. For three of the streams, more taxa were present in 1999 than recorded using comparable sampling methods in the 1960s and 1970s, despite lower numbers of individuals being recovered in 1999. Values of the Margalef diversity index could be calculated for both 1965-1972 and 1999 for four of the streams; the index was significantly greater in 1999 (P < 0.001) in three streams, and unchanged in one stream (the most acid). The 1999 survey revealed the presence of acid-sensitive taxa that had been absent in the earlier surveys, notably the three stoneflies Leuctra fusca, L. moselyi and Chloroperla tripunctata. Some taxa that had been present during 1965-1972 were absent in 1999, but few of these were acid-sensitive. Diatoms from the surface sediments of six lakes were classified according to their acid sensitivities. In three of the lakes sampled in 1999 there were more diatoms characteristic of circumneutral waters, and less acidophilic species than had been found in 1983-1985. In the remaining three lakes, no noticeable changes had occurred. Overall, the observed biological changes are qualitatively as expected for the observed increases in pH, and there have been no instances of biological change in the opposite direction. The results support the expectation that changes in freshwater ecological status can be reversed by decreasing the remote emissions of acidifying pollutants.

The gap between patient reading comprehension and the readability of patient education materials.

Patient education materials and hospital forms are given to patients with little regard for their ability to read them. Nationwide sampling and data from the 1980 census suggest that a high proportion of patients cared for in public hospitals are functionally illiterate. In this study, 151 adult primary care patients in five different ambulatory care settings were tested for reading comprehension. Patient education materials and forms from each clinic were analyzed for readability using a standard computer program. A large discrepancy was found between the average patient reading comprehension and the ability levels needed to read patient education materials. The average reading comprehension of public clinic patients was 6th grade 5th month. Most tested patient education materials required a reading level of 11th to 14th grade, and standard institutional consent forms required a college-level reading comprehension. In the public clinics there was a gap of more than 5 years between patient reading levels and the comprehension levels required by written patient materials.

The effects of prenatal stress on rat offsprings' learning ability.

The present study (N = 30 female rats, 11 male rats) was conducted to determine the effects of prenatal stress on rat offsprings' learning ability. Pregnant mothers were stressed by exposure to an SD (light) which had been paired with shock. A second group of pregnant rats was handled an equivalent amount of time, and a third group received no treatment. The offspring of the three groups were tested on several learning tasks and the handled and stressed groups were found to be inferior to the control group on four of six learning measures.

Attitudes toward homosexuality in Shreveport-Bossier City, Louisiana.

Two anonymous questionnaires assessing attitudes toward gay issues were administered to adults living in the Shreveport/Bossier City, Louisiana area. In both, demographic data were obtained regarding gender, education, religion, age and marital status. In the second questionnaire, family groups were given the questionnaire. In the first survey, the results generally supported previous findings that religiosity, gender, and education at or below the high school level appeared to be associated with negative attitudes toward gay and lesbian issues. The variable most frequently associated with positive attitudes toward gay and lesbian issues was whether or not the individual had at least one gay friend, relative, or acquaintance. In the second study, the questionnaire was analyzed in terms of the entire group of subjects, family groups, and family positions. This second questionnaire indicated that similarities are most likely to exist among mothers and daughters, and same sex siblings. In regard to family members, wives/mothers and daughters had more positive attitudes toward homosexuality than sons, fathers, grandparents, other relatives, and in-laws.

DESEMPEÑO PRODUCTIVO, COMPOSICIÓN Y BIODISPONIBILIDAD RELATIVA DE SELENIO EN TILAPIA NILÓTICA -Oreochromis niloticus- SUPLEMENTADA CON SELENIO ORGÁNICO E INORGÁNICO / PRODUCTIVE PERFORMANCE, COMPOSITION AND RELATIVE SELENIUM BIOAVAILABILITY IN NILE TILAPIA -Oreochromis niloticus- SUPPLEMENTED WITH ORGANIC AND INORGANIC SELENIUM

Se evaluó el desempeño productivo, la composición corporal y la biodisponibilidad relativa de selenio en tilapia nilótica (Oreochromis niloticus) suplementada con selenio dietario. Una dieta basal fue suplementada con selenio en forma de selenito de sodio o seleno-levadura en niveles crecientes de suplementación (0.00, 0.10, 0.20, 0.40, 0.80 y 1.60 mg/kg de dieta). Un total de 336 individuos de tilapia nilótica, con un peso inicial de 13.41±0.12 g, fueron distribuidos de forma aleatoria en 48 acuarios de vidrio (80 l, 4 réplicas, 7 peces por acuario). No se detectó selenio en el agua de abastecimiento. Los peces fueron alimentados hasta saciedad aparente 3 veces al día por un período de 9 semanas. El desempeño productivo de la tilapia nilótica no se vio afectado (P>0.05) por la suplementación con selenio dietario. El selenio corporal se incrementó de forma lineal (P<0.05) con la suplementación de selenio orgánico e inorgánico. La composición corporal de selenio fue menor (P<0.05) en los peces suplementados con selenito de sodio (1.67±0.14 mg/kg) en comparación con la seleno-levadura (1.95±0.21 mg/kg). A partir de la relación entre pendientes se estimó que la biodisponibilidad relativa de la seleno-levadura para la composición de selenio corporal fue de 155.72±0,10%, con relación al selenito de sodio (fijada en 100%). De acuerdo con los resultados, la concentración basal de selenio dietario (0.21 mg/kg) no limitó el desempeño productivo de tilapia nilótica. La suplementación con selenio orgánico (seleno-levadura) e inorgánico (selenito de sodio) entre 0.10 y 1.60 mg/kg no afectó el desempeño productivo de la tilapia nilótica.

The aim of this study was to evaluate the productive performance, whole body selenium retention and relative selenium bioavailability in Nile tilapia (Oreochromis niloticus). A practical basal diet was supplemented with either sodium selenite or seleno-yeast at tilapia fish (n=336) with an initial weight of 13.41±0.12 g were randomly distributed into forty-eight glass aquaria (80 l, 4 replicates, 7 fish per aquarium). There was no detectable selenium in supply water. Fish were fed the experimental diets to apparent satiation three times daily for nine weeks. Selenium supplementation did not affect the productive performance of Nile tilapia (P>0.05). Total whole body selenium increase linearly in response to dietary selenium supplementation (P<0.05). Fish fed sodium selenite had lower (P<0.05) whole body selenium (1.67±0.14 mg/kg) compared to fish fed seleno-yeast (1.95±0.21 mg/kg). Based on the slope-ratio assay for whole body selenium, the relative bioavailability of seleno-yeast was 155.72%±0.10 compared to sodium selenite (set at 100%). According to results the basal selenium content in expegraded selenium levels (0.0, 0.10, 0.20, 0.40, 0.80 and 1.60 mg/kg). Reversed Nile rimental diets (0.21 mg/kg) did not limit the productive performance of Nile tilapia. Supplementation of inorganic and organic selenium (0.10-1.60 mg/kg) did not affect the productive performance of Nile tilapia.

EFECTO DE LA INCLUSIÓN DE DIFERENTES FUENTES DE LÍPIDOS SOBRE PARÁMETROS PRODUCTIVOS Y COMPOSICIÓN PROXIMAL DEL FILETE DE TILAPIA NILÓTICA -Oreochromis niloticus- CULTIVADA EN JAULAS FLOTANTES / EFFECT OF THE INCLUSION OF DIFFERENT LIPID SOURCES ON GROWTH PERFORMANCE AND PROXIMATE COMPOSITION OF NILE TILAPIA FILLET -Oreochromis niloticus- REARED IN FLOATING CAGES

Para evaluar el efecto de la inclusión de diferentes fuentes de lípidos sobre el comportamiento productivo y la composición proximal del filete de tilapia nilótica Oreo-chromis niloticus, se formularon cuatro dietas con aceite de pescado (AP), aceite de palma (APL), semilla de chía (SC) o semilla de lino (SL). El experimento fue realizado durante 45 días en la represa de Betania (Huila, Colombia), en 20 jaulas flotantes, cada una con 504 peces con peso promedio de 557±16,87 g, distribuidos bajo un diseño experimental completamente al azar. Adicionalmente se llevó a cabo un estudio de presupuestos parciales, con el fin de verificar el margen bruto de ingreso parcial (MBIP) obtenido con las diferentes dietas. Se observaron diferencias significativas (P < 0,05) en el factor de conversión alimenticia (FCA) entre AP (1,19) y SL (1,54) y en la tasa de eficiencia proteica (TEP) para AP (3,64) al comparar con las demás dietas. Por su parte, la dieta que contenía SC generó el menor MBIP, seguido de SL, APL y AP. En la composición proximal de los filetes, únicamente se observaron diferencias significativas (P < 0,05) en el contenido de proteína cruda entre AP (18,23%) al compararlo con SL (19,17%). En conclusión, es posible utilizar AP, APL, SC o SL como fuentes de lípidos en las dietas, sin afectar la sobrevivencia, biomasa final, ganancia diaria de peso, consumo aparente de alimento, tasa específica de crecimiento e índice viscerosomático.

In order to evaluate the effect of inclusion of different lipid sources on growth performance and proximate composition of Nile tilapia Oreochromis niloticus fillet, four diets were manufactured with: fish oil (FO), palm oil (PO), chia seeds (CS) or flaxseeds (FS). The experiment was conducted for 45 days at Betania reservoir (Huila), in 20 floating completely randomized experimental design. In Addition, an economical partial budget analysis was run to establish the partial gross marginal income (PGMI) obtained with the different diets. Significant differences (P < 0,05) were observed in feed conversion ratio (FCR) between FO (1,19) and FS (1,54) and protein efficiency ratio (PER) among FO (3,64) and the other diets. The CS diet generated the lower IGMP followed by FS, PO and FO. In fillet proximal composition there were significant differences (P < 0,05) only in crude protein content, between FO (18,23%) compared with FS (19,17%). In conclusion it is possible to use FO, PO, CS or FS as lipids sources in the diet without affecting survival, final biomass, daily live weight gain, apparent food intake, specific growth rate and viscerosomatic index. cages, each one with 504 fish with mean live weight of 557 ± 16,87 g, distributed in a completely randomized experimental design. In Addition, an economical partial budget analysis was run to establish the partial gross marginal income (PGMI) obtained with the different diets. Significant differences (P < 0,05) were observed in feed conversion ratio (FCR) between FO (1,19) and FS (1,54) and protein efficiency ratio (PER) among FO (3,64) and the other diets. The CS diet generated the lower IGMP followed by FS, PO and FO. In fillet proximal composition there were significant differences (P < 0,05) only in crude protein content, between FO (18,23%) compared with FS (19,17%). In conclusion it is possible to use FO, PO, CS or FS as lipids sources in the diet without affecting survival, final biomass, daily live weight gain, apparent food intake, specific growth rate and viscerosomatic index.

EVALUACIÓN DE UN SISTEMA DE ALIMENTACIÓN ORGÁNICO SOBRE EL DESEMPEÑO PRODUCTIVO DE LA TILAPIA NILÓTICA (Oreochromis niloticus) CULTIVADA EN ESTANQUES DE TIERRA / EVALUATION OF AN ORGANIC FEEDING SYSTEM ON THE PRODUCTIVE PERFORMANCE OF NILE TILAPIA (Oreochromis niloticus) IN EARTHEN PONDS

Se evaluó el efecto de un sistema de alimentación integrado por dietas formuladas con recursos alternativos orgánicos y diferentes niveles de fertilización orgánica sobre parámetros zootécnicos en peces de consumo cultivados en estanques de tierra. Se utilizaron 1.324 juveniles de Tilapia nilótica (Oreochromis niloticus) cuyo peso inicial promedio fue de 161,9 ± 7,0 g, solo machos sexados manualmente, sin reversión hormonal. Se empleó un diseño completamente al azar con tres tratamientos y tres repeticiones, distribuidos en 9 estanques de tierra (200 m² cada uno), cultivados bajo las normas de Naturland (2007, 2008, 2011) para la acuicultura orgánica. Durante 180 días se suministraron dietas (levante: 27% PB y 4.120 cal/g EB; finalización: 21% PB y 4.200 cal/g EB) formuladas con recursos provenientes de producción agrícola orgánica certificada. Se implementaron tres variables: un control sin fertilizante y dos diferentes niveles de fertilización con gallinaza orgánica (T1: Abonamiento intensivo con 5 g/m²/día; T2: Abonamiento periódico con 14 g/m²/semana y T3: Sin abonamiento). Se evaluó el efecto de los tratamientos sobre parámetros productivos: ganancia diaria de peso, conversión alimenticia aparente, tasa de crecimiento específico, rendimiento en filete, índices viscerosomático, hepatosomático y de grasa visceral, relación de eficiencia proteica, valor productivo de proteína y eficiencia de retención de energía. No se encontraron diferencias significativas en las variables evaluadas (p>0.05). Los resultados indican la posibilidad de implementar un sistema de alimentación orgánico como alternativa productiva que logra parámetros productivos que se aproximan a lo reportado para explotaciones convencionales de tilapia y con el potencial de posicionar un producto final en eco-mercados diferenciales siendo sustentable en su obtención.

It was evaluated the effect of a feeding system that included formulated diets with organic alternative resources and different levels of organic fertilization on animal production evaluation parameters in fish farmed in earthen ponds. 1,324 juvenile Nile tilapia (Oreochromis niloticus) with initial weight of 161.9 ± 7.0 g, male manually sexed without hormonal reversal were used. It was used a completely randomized design with three treatments and three replicates, randomly distributed in 9 earthen ponds of 200 m² each. The husbandry management was under the Naturland standards for organic aquaculture. During 180 days fish were fed diets (growth: 27% CP and 4,120 cal/g GE; finish: 21% CP and 4,200 cal/g GE) formulated using resources from certified organic agricultural production. Were handled without fertilizer control and two different levels of organic chicken manure fertilization (T1: intensive fertilization with 5g/m²/day; T2: periodically fertilization with 14g/m²/week and T3: no fertilization). The effect of treatments was evaluated on: daily weight gain, apparent feed conversion, specific growth rate, fillet yield, viscerosomatic, hepatosomatic and visceral fat index, protein efficiency ratio, protein production value and energy retention efficiency. There were not significant differences in the variables evaluated (p<0,05). Results obtained suggest that it is possible to implement an organic feeding system to be a productive alternative that able to maintain production parameters approximate to that reported to conventional production, with potential to position the final product markets to be sustainable differential extraction.

Discrimination by olfactory cues in albino rats reflecting familiarity and relatedness among conspecifics.

The present investigation sought to determine whether albino rat pups could discriminate among familiar siblings, nonfamiliar siblings, familiar nonsiblings (foster littermates), and nonfamiliar nonsiblings (unrelated agemates) using only olfactory cues. Pairing all possible combinations of familiarity and kinship variables (six), the odors were presented in paired combinations to each of twelve experimental subjects. Results from dependent t tests indicated that the albino rat pups could discriminate between the following pairs of odors using only the olfactory sensory modality: (a) familial siblings and nonfamiliar siblings, (t = 3.41, p = .006); (b) familiar siblings and nonfamiliar nonsiblings, (t = 9.62, p = .001); (c) nonfamiliar siblings and nonfamiliar nonsiblings, (t = 3.15, p = .009); and (d) familiar nonsiblings and nonfamiliar nonsiblings (t = 2.58, p = .026).