A note on the use of the Catalasemetre in assessing the quality of milk

The Catalasemetre, for assessing the quality of raw and pasteurized milk, has been studied. No correlation was found between catalase activity and bacterial counts for farm bulk tank milks within the range 5.2 ± 10²-5.4 ± 10⁵ cfu/ml. Similarly, no relation was observed between catalase activity and somatic cell counts of milk (range of counts from 0.08 to 3.5). However, the catalase activity and bacterial count of pasteurized milks which had been pre-incubated at 21.C for 25 h in the presence of crystal violet-penicillin-nisin to inhibit Gram-positive bacterial growth were significantly related. Thus, the use of this pre-incubation procedure coupled with the Catalasemetre to estimate bacterial growth, has potential in assessing the keeping quality of pasteurized milk samples within 25.5 h of production. Results on the thermostability of native milk catalase are also presented.     

Characterization of ovarian follicular dynamics in dromedary camels (Camelus dromedarius)

Ovarian follicular dynamics was monitored by transrectal ultrasonography, for a period of 60 to 90 days, and its correlation with plasma estradiol-17β (E2) and progesterone (P4) were studied in seventeen, multiparous, non-lactating, 12 to 20-year-old dromedary camels. The average number of follicles recruited (12.77 ± 0.93) in each wave between animals varied (P < 0.001). The number of follicles recruited during different follicular waves was highly repeatable (0.95) within individual animals. The growth and mature phase periods of the dominant follicle (DF) were 6.10 ± 0.15 and 10.20 ± 0.47 days, respectively with a linear growth rate of 1.17 ± 0.02 mm/day between Day 0 and 10 of the follicular wave. There was an inverse relationship between the diameter of the largest DF and number of follicles (r = −0.95, P < 0.001). The DF development did not regularly alternate between the ovaries and the incidence of codominance was 45%. The mean maximum diameter of DF during its mature phase was 27.30 ± 0.78 mm and oversized follicle was 38.43 ± 1.41 mm. In 73.3% waves, the DF continued its growth for a period of 10.64 ± 1.53 days even after losing its dominance and developed into oversized follicle. The duration of the regression phase of DF and oversized follicle were 24.71 ± 3.79 and 18.50 ± 2.23 days. The mean duration of a complete follicular wave was 47.11 ± 2.94 days with an interwave interval (IWI) of 16.36 ± 0.37 days. The IWI within an individual was repeatable (0.88) and between the animals was variable (P < 0.001). Plasma E2 concentration profiles showed a wave like pattern. The peak plasma E2 concentrations were attained approximately 12 days after beginning of the growth phase, when the largest DF grew to a diameter of 18.7 mm. Plasma concentration of P4 was below 1.0 ng/mL in 85% of waves and above 1.0 ng/mL in 15% of the waves for a period of 3 to 6 days in the absence of spontaneous ovulation. It is concluded that ovarian follicular development and plasma E2 concentrations occurs in a wave like pattern in dromedary camels and the IWI and follicle numbers recruited per wave are variable between the animals and repeatable within an individual animal.     

A preliminary note on the Genetics of Fragaria

Ohne Zusammenfassung

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A preliminary note on the Genetics of Fragaria

     

A preliminary note on Incurvarioidea in New Zealand

Abstract

The Monotrysian superfamily Incurvarioidea (Lepidoptera) is now known to be present inNew Zealand. A mummified partly decayed male, parasitised pupae, larval head capsules, and characteristic cocoons are associated with long (1500–2000 mm) meandering cortical scribble-like mines in sapling Weinmannia, Nothofagus and Myrsine. The fragments and larval biology display features of Prodoxidae, but cannot be assigned to a genus.

Wing pattern, some forewing venation, pupal structure, male genitalia and some female ovipositor structures, larval head capsule and pronotum, and details of the pupal cell and larval mine are described and illustrated.     

A preliminary note on the rainbow in Africa South of the Sahara

This article is the product of a focussed reading of Louis Dumont with a view to two particular interests: modernity and the place of gender not only within modern discourse, but also in modern practice. Though polemical in form, the intention is to shed new light on the ongoing debates of gender by addressing them within Dumont's theoretical framework. Starting with some reflections on vantage point and gendered positioning, the author proceeds to discuss the modern notion of the individual, suggesting that the autonomous agent in modern society is the couple. Drawing on both Bateson and Rappaport, she considers the notions of hierarchy, logical scandal and the place of ultimate values in relation to change.     

Incidence of spontaneous ovulation and development of the corpus luteum in non-mated dromedary camels (Camelus dromedarius)

The occurrence of spontaneous ovulation in dromedaries was examined in two separate studies including 20 non-lactating, barren and 12 lactating dromedaries, respectively. Lactating camels were milked twice a day with an automatic bucket milking machine. Ovarian activity was monitored by repeated ultrasonography. Blood samples for progesterone were collected daily or two to three times a week. To compare CL development after spontaneous and induced ovulations, ovulation was induced by a GnRH analogue in eight lactating dromedaries. Spontaneous ovulation was observed in one non-lactating camel (1 of 20 camels, 5%; 1 of 70 follicular waves, 1.4%), whereas, spontaneous ovulation was detected more frequently in lactating dromedaries (5 of 12 camels, 41.7%; 13 of 91 follicular waves, 14.3%). In one lactating camel, spontaneous ovulation occurred repeatedly for nine times. There was a significant effect of type of ovulation (spontaneous versus induced, P < 0.05) and day (P < 0.001) on serum progesterone concentration. Mean serum progesterone levels and total progesterone production (AUC) were higher after induced ovulation. Luteal diameter and serum progesterone concentration were positively correlated (r = 0.71, P < 0.001), but there was a significant difference between morphological and functional development of the CL. In dromedaries, morphological development starts earlier, morphological regression starts later and last longer than functional development and regression of the CL. Compared to induced ovulation, functional development of the CL after spontaneous ovulation might be altered but the morphological development is not affected.     

A comparative study of elemental composition of human breast milk and infant milk substitutes

Instrumental neutron activation analysis (INAA) and protoninduced X-ray emission (PIXE) analysis have been employed to determine the concentration of 13 elements in human breast milk, various infant formulas, and locally produced cereals from Nigeria, as well as from various infant formulas and natural cow and goat milk available in the UK. The study shows that if the locally produced cereal is to be used on a regular basis for babies in Nigeria, then their diet must be supplemented with essential trace elements. Furthermore, parents should be discouraged from giving their infants cow and goat milk because of the high concentration of major elements compared to human breast milk.     

Effect of progesterone from induced corpus luteum on the characteristics of a dominant follicle in dromedary camels (Camelus dromedarius)

The present study was carried out to elucidate the effect of progesterone (P4) from the induced corpus luteum (CL) on the characteristics of the dominant follicle (DF) in dromedary camels (Camelus dromedarius). Ovarian follicular and induced CL dynamics were monitored by transrectal ultrasonography in eight camels during the peak breeding season. The characteristics of the DF were monitored daily from the day of emergence into a wave, until it appeared to lose its dominance and the DF of a subsequent wave grew to a diameter of 13-17 mm. At this stage ovulation was induced by hCG and the DF was monitored every 8 h for 48 h. After ovulation, CL dynamics and follicular development (emergence of a new wave, growth and mature phase of the selected DF) were monitored daily. Blood samples were collected during each ultrasound examination to study the P4 profile in these animals. The CL developed to a maximum size (22.55 ± 3.24 mm) with a peak concentration of P4 (4.60 ± 2.57 ng/ml) 7 days after ovulation. The size of the CL was positively correlated with the P4 concentration (r = 0.612) during the different stages of the CL dynamics. The presence of CL did not affect the linear growth rate, duration of growth and mature phases of the DF. The development of the DF to its maximum size during its mature phase and inter-wave interval were not affected by the P4 secreted by the induced CL. In conclusion, there is no evidence from this study to suggest that P4 from induced CL altered the characteristics of a DF in dromedary camels.     

Comparison of pregnancy rates in dromedary camels (Camelus dromedarius) after deep intra-uterine versus cervical insemination

The ovarian follicular wave patterns of sixty adult female camels were monitored by serial trans-rectal ultrasound examinations and when the dominant follicle reached 1.3-1.8 cm in diameter they received a single intravenous injection of 20 microg buserelin, to induce ovulation, and were inseminated with a known number of spermatozoa 24 h later. Ejaculates were collected from the male camels and diluted 1:1 in Green Buffer with 20% egg yolk (v:v) added. Sperm concentration and motility were assessed and a dose of 40, 80 or 150 x 10(6) motile spermatozoa were deposited either just through the cervix into the uterine body or at the tip of the horn ipsilateral with the ovary containing the dominant follicle. Insemination of 150, 80 and 40 x 10(6) spermatozoa into the uterine body resulted in conception rates of 53, 7 and 0%, respectively, whereas insemination at the tip of the uterine horn resulted in conception rates of 43, 40 and 7%, respectively.     

A preliminary note on the hormonal induction of NADP-linked dehydrogenases in phytohaemagglutinin-stimulated human lymphocytes

Synopsis Human leucocytes were culturedin vitro with either phytohaemagglutin or 17 -oestradiol or both, and the enzyme activities of nicotinamide adenine dinucleotide phosphate-linked glucose-6-phosphate dehydrogenase and isocitrate dehydrogenase were assayed. As a result, it was found that these enzymes were considerably induced by oestradiol in phytohaemagglutinin-stimulated lymphocytes, but not in non-stimulated cells. Electrophoretic studies on glucose-6-phosphate dehydrogenase showed that six molecular forms are demonstrable in normal and phytohaemagglutinin-stimulated leucocytes, and that one of the forms was specifically induced by oestradiol in the presence of phytohaemagglutinin.     

A cautionary note on the use of stable transformed cells

Gene transfection and ectopic expression is a widely used method in experimental biology. In the present report, we would like to point out that this approach may, in certain circumstances, lead to a modification of the transfected cell phenotype. Indeed, we observed that after transfection of bcl-2 gene in the neuronal PC12 cell line some of the selected clones have lost their neuronal and catecholaminergic characteristics, i.e. TH expression and ability to grow neurites in response to NGF. Thus, the resistance of some PC12-Bcl-2 clones against neurotoxic insults may not necessarily reflect the potential benefit afforded by Bcl-2 expression. We therefore encouraged authors to verify cell phenotype after stable transfection to avoid misinterpretation of their results.