The low proportion of forested land and continuing degradation of existing forest cover are serious threats to the sustainability of forestry in Pakistan. Farm forestry has been identified as a feasible solution, particularly in the plain areas. Applying the Theory of Planned Behaviour in a survey of 124 farmers in Dera Ismail Khan district of Pakistan's North West Frontier Province showed that farmers' willingness to grow trees on their farms is a function of their attitudes towards the advantages and disadvantages of growing trees, their perception of the opinions of salient referents and factors that encourage and discourage farm level tree planting. Farmers viewed farm forestry as economically beneficial and environmentally friendly. Tree planting was perceived as increasing income, providing wood for fuel and furniture, controlling erosion and pollution and providing shade for humans and animals. Farmers saw hindrance in agricultural operations and the harbouring of insects, pests and diseases as negative impacts of tree planting; however, these were outweighed by their perceptions of positive impacts. Tree growing decisions of farmers were influenced by the opinions of family members, owners/tenants, fellow farmers and village elders. The factors that significantly predicted farm level tree planting were availability of barren land, lack of markets, lack of nurseries and damage caused by animals and humans. Farm forestry programmes are more likely to be successful if they acknowledge and address the factors which underlie farmers' reasons for planting or not planting trees.

Arsenic is an environmental toxicant which causes mutagenic, teratogenic and carcinogenic defects. It is used as herbicide, fungicide and rodenticide and results in contamination of air, soil and water. Arsenic is also produced through burning of coal industries. The sludge of factories contaminates the fodder and drinking source of water of human and livestock. Arsenic binds thiol groups in tissue proteins and impairs the function of the proteins. This metal affects the mitochondrial enzymes and interrupts the production of energy. Oxidative stress and the generation of reactive oxygen species could also be a consequence of arsenic exposure. High arsenic level may suppress the sensitivity of gonadotroph cells to GnRH as well as gonadotropin secretion by elevating plasma levels of glucocorticoids. These ultimately lead to the development of gonad toxicity in animals and cause the reduction in sperm number, sperm viability and motility. Massive degeneration of germ cells and alterations in the level of LH, FSH and testosterone are also reported. The objective of this review was to find out the effects of arsenic-induced toxicity on male reproductive system in animals and its amelioration.

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The hypo-osmotic swelling test (HOST) is widely used as a valuable test for determining sperm quality by evaluating the membrane integrity of spermatozoa of various domestic animals including cattle, horses and swine. The HOST has also been used as an indicator of the fertilising capacity of spermatozoa. This test is based on the swelling ability when functional spermatozoa submitted to hypo-osmotic solutions. This test is commonly used as an important parameter for the evaluation of semen due to its strong correlation with semen evaluation parameters. The objective of this review was to analyse its significance in semen evaluation, swelling of spermatozoa under various osmolarities and variations in swelling percentage under different seasons.