Halophytic and Salt-Tolerant Feedstuffs: Impacts on Nutrition, Physiology and Reproduction of Livestock PDF

Preface

Use of halophytes as animal feedstuffs attracted attention of scientists toward the latter half of the twentieth century with the appearance of scientifi c papers1 on effect of brackish drinking water and salty feed on animal health and meat quality/quantity and the problems encountered in such studies were identifi ed. Subsequently, scattered reports appeared in the literature where scientists from Australia, India, Pakistan, Middle East, Africa and North/South America working in the relevant fi elds have attempted replacing the regular fodder with one or another halophyte or salt tolerant feedstuff.

Later, a series of monographs and edited multi-author books* on aspects of the physiology of salt tolerant plants animals were published. Attention was also focused on the use of salt tolerant plants that included obligate halophytes, as candidate species for rehabilitation of saline lands, including abandoned irrigation areas. The role of biomass produced on such rehabilitated lands and new ways to use such biomass, especially in mixed rations involving more conventional fodders, was also investigated. As the loss of arable land to secondary salinity became more widespread and as the agronomy of salt tolerant food crops was advanced attention turned to utilizing the crop by-products, including oil seed cakes and meals. Sea water irrigation of halophytes gained traction as the search for commercially viable biosaline systems were advanced. This development generated a larger quantity of potentially usable feedstuffs both as biomass and as by-product such as seed cake.

Finding suitable forage/fodder (and even grain crops) which does not encroach upon the land under conventional crops may be useful for cattle raising and meeting the requirement of meat, poultry and dairy products is a challenge and specialized research centers were established, principally in the Gulf region, the WANA region, Pakistan, Central Asia and USA (Arizona) and Australia. Concurrently there was interest in using halophytes for remediation of damaged lands, including mine sites. The potential of salt tolerant plants, including extreme halophytes, for carbon sequestration also received attention. Some of the biomass derived from C sequestration plantations began to enter the supply chain for feedlots where guaranteed supplies of high quantities of suitable feedstuffs are required. In addition to salt tolerant and halophytic plants grown under intensive cultivation there are extensive areas of naturally-occurring shrublands, woodlands and grasslands that are used as fodder reserves or protein supplements, either grazed/bowsed by livestock or in cut-and-carry systems.

The volume of data generated and the interest in fi lling the ‘feed gap’ in many animal production systems, especially in arid and semi arid regions, has provided impetus to convene International and, regional and national symposia and spawned special issues of journals (e.g., Small Ruminant Nutrition) and various conference proceedings. The plethora of information generated by nutritionists, animal physiologists, veterinarians, agronomists and livestock specialists is scattered throughout reports, journal articles and some specialist monographs but lacks integration and synthesis into a coordinated body of knowledge. In this book we attempt a synthesis that considers the role and potential of salt tolerant and halophytic feedstuffs and their impacts on nutrition, physiology and reproduction of livestock, including ruminants and non ruminants such and poultry and rabbits.

¹ See a list of these in the various reference lists at the end of each chapter.

* See footnote 1.