Zinc deficiency is not only the cause of low productivity of crops, but it also results in low zinc content in seeds, which leads to poor dietary zinc intake. To study the effect of zinc foliar application on improving plant yield and seed zinc content for human consumption, chickpea plants were raised in refined sand culture with deficient (0.2 μM) and sufficient (1μM) supply of zinc under gla...

The intraspecific interference of a top-predator is incorporated into a classical mathematical model for three-trophic food chains. All chaos types known to the classical model are shown to exist for this comprehensive model. It is further demonstrated that if the top-predator reproduces at high efficiency, then all chaotic dynamics will change to a stable coexisting equilibrium, a novel proper...

For most beef cow herds, the single most important means of increasing income is increasing the number of calves weaned and sold, relative to the number of cows in the operation, or by definition, increasing reproductive efficiency. While certain production and carcass traits can be most directly influenced by genetic selection, reproductive performance is overwhelmingly influenced by managemen...

Infertility has been linked to numerous factors in high producing dairy cattle in the last decades. The detection of estrus continues to present difficulties and, although progress has been made in regards to estrus synchronization and artificial insemination, the reproductive performance of dairy cows has not improved substantially. Moreover, in warm countries, summer heat stress is a major fa...

The red color pattern in some strains of tilapia has added commercial value in some markets. Although red tilapia may be more marketable, questions have arisen regarding its value as a culture fish. El Gamal (1987) reported that during growout from 130 to 262 g, a red strain of tilapia had significantly lower survival than Oreochromis aureus x Oreochromis aureus and Oreochromis niloticus x Oreo...

Buffaloes play a prominent role in rural livestock production, particularly in Asia. Reproductive efficiency is the primary factor affecting productivity and is hampered in female buffalo by (i) inherent late maturity, (ii) poor estrus expression in summer, (iii) distinct seasonal reproductive patterns, and (iv) prolonged intercalving intervals. Ovarian function is central to these issues; henc...

Nine measures related to breeding efficiency were used for comparisons among purebred Ayrshires, Brown Swiss, Holsteins, and Jerseys and between purebreds and 32 crossbred groups representing 2-breed, 3-breed, 5/8, and backcrosses by purebred sires and progeny of crossbred sires. There were four herds wi th Holsteins common to all, Brown Swiss and Jerseys in three herds and Ayrshires in one her...

Primordial follicles comprise an oocyte surrounded by a single layer of squamous epithelial cells, called pregranulosa cells (Peters, 1978; Greenwald and Terranova, 1988). Enlargement of the oocyte and initiation of granulosa cell division mark the beginning of follicular growth (Peters, 1978). Soon after initiation of growth, the pregranulosa cells, which form the simple squamous epithelium of...

Lipotoxicity is characterized by excessive saturated fatty acids in the blood, increasing storage in non-adipose cells, which leads to changes in the expression pattern of genes related to endoplasmic reticulum stress (e.g., ATF4, ATF6, CHOP, and GRP78), proand anti-apoptotic pathways (e.g., Bax and Bcl-2, and protein stability, including heat shock proteins, e.g., HSP70). A negative sub-cellul...

In this study, we investigated the age-dependent changes in reproductive efficiency of Kutum, Rutilus frisii  caught  from Shirood River,  the Southern Caspian Sea (Mazandaran Province, Iran). Age-dependent reproductive performance of brooders was assayed on two age and sex groups. Results revealed thatthere were no significant differences in sperm characteristics between age groups. All female...