Attainment of Puberty in the European Mouflon (Ovis gmelini musimon) and the Domestic Manchega Ewe (Ovis aries)

The onset of puberty was assessed from plasma progesterone profiles for Mouflon (n = 8) and Manchega (n = 7) female lambs born in April. Four Mouflons exhibited their first ovulation at a mean date of 27 November ± 1.4 days, the mean age being 248.5 ± 3.9 days and the mean body weight 23.8 ± 0.6 kg. The remaining four Mouflons, which had a slower growth rate, attained puberty during the autumn of the following year. Five of seven Manchega lambs attained puberty in their first year at a mean date of 5 Oct ± 3.3, the mean age being 185.6 ± 2.6 days and the mean body weight 41.8 ± 2.0 kg. The mean live‐weight at the onset of puberty was 65.1 and 82% (p < 0.05) of adult body weights for Manchega and Mouflons, respectively. Overall, the results indicate that there is a threshold of body‐weight necessary for the attainment of puberty in the first breeding season for spring‐born lambs, which is very different between both Mouflon and Manchega. When body weight was below 23.8 ±0.6 and 41.8 ± 2.0 kg for Mouflon and Manchega lambs, respectively, first ovulation did not occur until the beginning of the next breeding season. The onset of puberty during the second year of life occurred within the specific reproductive seasons for Mouflon (October–April) and Manchega (July–March) ewes, despite minimal further growth.     

Development of TGMS lines for developing two-line rice hybrids for the tropics

A breeding program was initiated at the International Rice Research Institute (IRRI) in 1990 to develop thermosensitive genic male sterile (TGMS) rice lines for developing two-line rice hybrids for the tropics. The TGMS trait was transferred from a temperate japonica TGMS mutant, Norin PL 12, to indica and tropical japonica rice varieties using the pedigree selection procedure. Six new TGMS rice lines adapted to tropical conditions were developed which showed complete pollen and spikelet sterility when maximum temperature was higher than 30 ^°C 1–2 week after panicle initiation. However, up to 85.5% spikelet fertility was observed when these lines were exposed to 26–29 ^°C during the critical stage. Using two of these TGMS lines, some heterotic rice hybrids showing 1–1.6 t/ha higher grain yield than the inbred check varieties were identified in unreplicated observational yield trial conducted at IRRI. Two of the six two-line hybrids yielded significantly higher than the check variety in a replicated preliminary yield trial. This revised version was published online in July 2006 with corrections to the Cover Date.     

Effect of cutting and vacuum cleaning on the digestibility of oats by horses

Three mature Quarter Horse geldings were used in 2 Latin square experiments to measure the effect of cutting and vacuum cleaning of oats on digestibility. The horses were fed at the maintenance level of digestible energy (DE) as recommended by the NRC.¹²The data were analyzed by Latin square analysis of variance, and Tukey's t test was used to determine any differences between specific means.No significant differences among treatments were observed during either experiment, indicating that the digestibility of nutrients from oats was not affected by cutting and vacuum cleaning. Differences in the digestibility of the ether extract (EE) fraction between periods of experiment 1 were noted.     

Effect of sex, age, number of bronchoalveolar lavages and quantitation methods on the bronchoalveolar cell counts in rats.

This study was conducted to investigate the effect of sex, age, number of bronchoalveolar lavages and method of quantitation on the number of bronchoalveolar cells in rats. Forty Long Evans rats were divided into four age-sex subgroups of ten animals each. Nine consecutive bronchoalveolar lavages were done in every rat and the number of bronchoalveolar cells/mL in lavages 1-3 (L1), 4-6 (L2) and 7-9 (L3) were determined by hemocytometer and electronic cell counts (Coulter Counter). The sex or age of the rats did not show a significant effect (p less than 0.05) in the number of bronchoalveolar cells recovered from the lungs; however, there was a significant difference (p less than 0.05) in the number of cells/mL among lavages 1-3, 4-6 and 7-9 (L1 approximately equal to L2 greater than L3). A discrepancy of approximately 8% in the counts of bronchoalveolar cells was found between the hemocytometer and the Coulter Counter; however, these two methods of cell quantitation showed a significant (p less than 0.01) positive correlation (r = 0.89). No significant (p greater than 0.05) differences were found in the percentage of fluid recovery (overall mean = 94.5%) among lavages L1, L2 and L3. It was concluded that the electronic cell counting of bronchoalveolar cells is as reliable as manual counting. Although sex or age did not significantly affect the number of cells recovered from the lung, caution should be used in the number of lavages done per rat since this variable may significantly affect the results.     

Estimation du stock semencier dans le cadre d'un essai étudiant l'influence de systémes culturaux sur l'évolution de la flore adventice

Estimation of seed stock during a trial study of the influence of cultural systems on the development of the weed flora Twelve plots (12 × 20 m) were sampled at the En Crambade inter-institute station in 1984 before a 9-year trial (3×3 year rotations) was begun to study the influence of weed control methods, soil cultivation and crop rotation on the development of the weed flora. Three hundred cores, 25 per plot, were analysed separately. The weed species were identified and classified in accordance with their size and distribution. Sampling error as a function of the number of cores sampled, the variation and the average number of seeds per core were calculated.     

Nasal lesions in rats exposed to hydrogen sulfide for four hours

Fischer-344 rats were exposed for 4 hours to 0, 14, 280, or 560 mg of hydrogen sulfide.m-3 and killed 1, 18, or 44 hours later. We evaluated the nasal epithelial cells and determined the anatomic distribution of lesions. Inhalation of 560 mg of hydrogen sulfide.m-3 induced necrosis and exfoliation of respiratory and olfactory mucosal cells, but not squamous epithelial cells. The anatomic distribution of lesions was midway along the nasal passages involving nasal and maxillary conchae, but not ethmoidal conchae. Injured respiratory mucosa repaired rapidly, whereas olfactory mucosa continued to exfoliate at 44 hours after exposure.     

Cronología de Osificación Postnatal del Autópodo Torócico en el Gato Siamés (Felis catus L.)*

Chronology of the postnatal ossification of the Thoracic autopodo in the Siam cat (Felis catus L.) A study was done by radiological techniques to show the chronology of ossification of the thoracic autopodo of the Siam cat from birth up to the 25th week of postnatal development. For this experiment we used 40 little cats (19 males and 21 females) belonging to 11 litters subjected to different controls: pattern race, healthy, feeding, grow up and radioactivity. The time of the appearance and evolution of the centres that form the basipodo, metapodo and acropodo of the thoracic limb is determined. Likewise it is analized the phenomenon of fusion during that time to define the main ossification sequence in the carpo. The aspects of the postnatal ossification of the thoracic autopodo in the Siam cat are compared with the literature of differents authors about the common cat.