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The structure of the zooplankton community in Itapeva Lake was formed by four groups and more than 127 zooplankton species, in which microplankton was the predominant size structure. The largest richness recorded was of the protists group and in autumn seasonal campaign. Protists were characteristic of the lake, regarding density, except during spring at the Center point (copepods) and autumn at the South point (rotifers). The seasonal distribution revealed that during summer, mean density increased in the zooplankton community, exactly the opposite of phytoplankton (that blooms during the cold season). However, the maximum density was recorded during autumn. High density was recorded for the ciliate Codonella sp. at all points and during all seasons. The abundance of the tecamoeba Difflugia tuberculata was strongly associated with the maximum effects of fetch in the lake. Rotifers were generally the second most representative groups in terms of density. Rotifers and Cladocera were more abundant in summer, whereas copepods were in spring and winter/98. The Shannon–Wiener index showed that the smallest zooplankton diversity average occurred during the winter/98 (H=1.44), while in autumn the largest zooplankton diversity average (H=2.36) was observed. Correlations (r-Pearson, p<0.05) with wind velocity were significant for zooplankton density (groups and/or abundant species), diversity, and richness. The analysis of variance (ANOVA) showed a seasonally significant spatial-temporal variation for the factors sampling point, day and shift (p<0.01). Temporal alterations in density, diversity and richness were closely dependent on the hydrodynamic action induced by the wind on the spatial distribution of the zooplankton community in the Itapeva Lake. [ABSTRACT FROM AUTHOR]

Buffaloes are one of the major contributors in refining the rural economy, particularly in South and South-East Asia countries. There are about 177.5 million buffaloes in the world and more than 96 % of which are found in Asia. Though genetic improvement of this animal resource is imperative for milk and meat, it is limited by inherent biological attributes such as, long generation interval, long inter-calving period, longer age at sexual maturity, delay in puberty, distinct seasonal reproductive pattern, silent estrous, repeat breeding and eventually low reproductive rates. However, advancement in reproductive bio-techniques offers greater prospects to achieve the desired genetic improvement in buffaloes. Artificial insemination (AI) using frozen semen is well established and manipulation of ovarian function for estrus synchronization is used in large farms commonly. Super ovulation to produce embryos in vivo yielded average transferable embryos, 1.8-2.1 per collection. With advancement, embryo production using ovum pick-up (OPU) in combination with in vitro maturation (IVM) and fertilization (IVF) has been tried to a limited extent, but it is impending to be an alternative to earlier one. Recently advanced "Hand guided Cloning Technique", a landmark technique developed at National Dairy Research Institute (NDRI), Karnal could go a long way for faster multiplication of superior milch buffaloes in India. [ABSTRACT FROM AUTHOR]