Impacts of Institutional Reforms on Irrigated Agriculture in Pakistan

Poor functioning of theirrigation system in Pakistan has been asource of concern for the last few decades,during which time it has been the subject ofconsiderable external assistance andinternal policy reforms. Consequently, thegovernment of Pakistan introducedinstitutional restructuring in irrigationand drainage subsectors to impartnecessary improvements. Under thesereforms, management at secondary canallevel has recently been handed over to theFarmers Organizations (FOs) of selecteddistributaries in pilot areas. This studywas designed to evaluate a farmer-manageddistributary in southern Punjab. Fieldmeasurements revealed that hydraulicaspects of the irrigation service deliveredby the FO management has been significantlyimproved and as a result highlyproportionate and equitable waterdistribution was observed, particularly atthe tail reaches of the distributary. Dueto effective FO management farmers'interventions to increase the outletdischarge by illegal means has been almosteradicated. As a result of theseimprovements imparted by the FO in systemmanagement, the extent of irrigated area hasincreased on average by 6 to 7%, evenunder severe drought-like conditionsprevailing in the country during recentyears. Further cost recoveries haveincreased by an amount of 14% for summerand 23% for winter growing seasons,respectively, from the irrigated area of thedistributary. Thus experience from Hakra4-R distributary has shown that even underundesirable natural circumstancesIrrigation Management Transfer (IMT) wasquite effective in achieving the keytargets of the institutional reformslaunched at pilot scale in the country.     

A study of water distribution from a branch to distributary canals: A case study of Gugera Branch,Punjab, Pakistan

This study was conducted on Gugera Branch of Lower Chenab Canal, Punjab, Pakistan. Sample distributaries off taking from Gugera Branch were selected for the study. The existing conditions of water distribution among the distributaries were studied. Field data were collected during the whole of 1988. Field observations suggested that the variability at the head of distributaries is much greater than the variability in the Gugera Branch under existing operational practices. The distribution of water among the distributaries is rarely in accordance with design criteria. Some channels get priority over other channels. The annual closure period varied from 17 to 41 days for different channels. The discharge at the head of distributaries remained lower than the standard operational range for 69 to 183 days in a year. The data suggested that a regulating gate at the head of the distributary can reduce discharge variation up to 2.4 times compared with a Karrees System (wooden stop logs used for water regulation). The data indicated that the adjustments in the head gate of a distributary on daily basis can substantially improve discharge conditions at the head of distributary. Rotational schedules are not being followed as per design and need to be improved. Most of the existing head discharge relationships of discharge measuring structures are not reliable. A frequent calibration of these structures is recommended.     

Meat and Bone Meal as Partial Substitute for Fish Meal in Nursery Diet for Giant Freshwater Prawn, Macrobrachium rosenbergii (de Man)

An experiment was conducted for 60 d in a recirculatory system consisting of 20 glass aquariums (each of size 41 × 41 × 46 cm) to evaluate meat and bone meal (MBM) as partial replacement for fish meal (FM) in Macrobrachium rosenbergii postlarvae (PLs) with a view to develop an inexpensive nursery diet. Three nursery diets were formulated to contain 32% protein and to be as isoenergetic as possible. FM in these diets was progressively replaced with MBM (Diet 1 contained 25% FM and 14% MBM, Diet 2 contained 20% FM and 20% MBM, and Diet 3 contained 15% FM and 26% MBM). Inclusion levels of mustard oilcake and sesame meal in diets were kept fixed at 10%. A commercial shrimp nursery diet (30% protein) from Saudi Bangla Fish Feed Ltd., Mymensingh, was used as the reference diet (Diet 4). Each treatment had three replicates. PLs of M. rosenbergii (26 ± 0.02 mg) were stocked at the rate of 60 PLs (1 PL/L) in each aquarium. At the beginning, PLs were fed three times daily at a rate of 20% of the body weight and it was gradually reduced to 10% at Day 30. The ranges of water quality parameters in the system were as follows: temperature, 27–29 C; dissolved oxygen, 6.5–8.4 mg/L; pH, 6.8–8.3; and total ammonia, 0.01–0.15 mg/L. The result of the study showed that there was no significant difference (P > 0.05) between the weight gains of PLs fed Diet 1 (containing 14% MBM) and Diet 4 (reference diet) but was significantly higher than other dietary groups containing higher levels of MBM. Diets 1 and 4 showed significantly lower (P < 0.05) apparent food conversion ratios (1.74 and 1.73, respectively). The survival (%) of PLs ranged between 62 and 76% with PLs fed Diets 1 and 4 showing significantly higher (P < 0.05) survival. The result of the study demonstrated that the MBM could be included at 14% level in a nursery diet, and a diet containing 25% FM, 14% MBM, 10% sesame meal, and 10% mustard oilcake may be recommended for profitable production of PLs of M. rosenbergii.     

Post mortem studies on infertile buffalo bulls: anatomical and microbiological findings

Twenty-two buffalo bulls suffering from three different types of infertility were slaughtered and used for this study. Except for the reproductive system, no signs of localised or generalised disease were observed. Microbiological investigations were negative for brucellosis, vibriosis, mycoplasma and other non-specific microorganisms. Nine bulls with type 1 infertility had low bodyweights and underdevelopment of testes, accessory sex glands and endocrine glands. This picture suggests a total dysfunction of the pituitary-growth-gonadal axis. One bull of this type also showed bilateral epididymitis. Four out of 11 bulls with type 2 infertility had low bodyweights and most suffered from underdevelopment of testes, accessory sex glands and endocrine glands. Six bulls of this type had lesions of either epididymitis or orchitis or both. Two of these animals showed adhesions of periorchitis. One also showed seminal vesiculitis. In two bulls with type 3 infertility, bodyweights, reproductive organs and endocrine glands were normal. In later life, they yielded poor quality semen. Semen samples collected a few months before slaughter from nine bulls with type 2 and type 3 infertility were of poor quality and had higher percentages of abnormal spermatozoa in most cases.     

Causes of Decadal Climate Variability over the North Pacific and North America

The cause of decadal climate variability over the North Pacific Ocean and North America is investigated by the analysis of data from a multidecadal integration with a state-of-the-art coupled ocean-atmosphere model and observations. About one-third of the low-frequency climate variability in the region of interest can be attributed to a cycle involving unstable air-sea interactions between the subtropical gyre circulation in the North Pacific and the Aleutian low-pressure system. The existence of this cycle provides a basis for long-range climate forecasting over the western United States at decadal time scales.     

Prevalence and genetic diversity of Anaplasma marginale strains in cattle in South Africa

Bovine anaplasmosis, caused by the tick-borne rickettsia Anaplasma marginale, is endemic in South Africa and results in considerable economic loss to the cattle industry. This study was designed to characterize strains of A. marginale at the molecular level from cattle raised in communal and commercial farms in the north-eastern and south-western regions of the Free State Province, South Africa, that varied in rainfall and vegetation. Seroprevalence to A. marginale was determined in 755 cattle by an Anaplasma spp. competitive enzyme-linked immunosorbent assay and ranged from 44% to 98% and was similar in both regions. While Anaplasma centrale was not targeted in this study, A. marginale infections were identified by species-specific msp1alpha polymerase chain reaction in 129 of 215 of the samples studied. Similar genetic diversity of A. marginale strains was found in both the north-eastern and south-western regions. The sequences of 29 A. marginalemsp1alpha amplicons from South African strains revealed considerable genetic diversity providing 14 new repeat sequences. However, 42% of MSP1a repeat sequences were not unique to this region. These results indicated the presence of common genotypes between South African, American and European strains of A. marginale. Cattle movement between different parts of South Africa was suggested by the presence of identical A. marginale MSP1a genotypes in north-eastern and south-western regions of the Free State Province. Control strategies for anaplasmosis in South Africa should therefore be designed to be protective against genetically heterogeneous strains of A. marginale.     

Prevalence of Sarcocystis spp. in meat-producing animals in Iraq.

The prevalence of Sarcocystis spp. infection was investigated in 605 sheep, 826 goats, 1080 cattle, 580 water buffaloes and 36 camels slaughtered from 1992 to 1996 in the Baghdad area (Iraq) using naked eye examination for macroscopic sarcocysts, and peptic digestion, muscle squash, squeezing methods and indirect fluorescent antibody test (IFAT) for microscopic types. The intestinal stages of the parasite were also studied in dogs experimentally fed with tissues containing microscopic cysts. The percentage prevalence of macroscopic cysts were 4.1, 33.6, 0.2, 15.6 and 0, and of the microscopic type, 97.0, 97.4, 97.8, 82.9 and 91.6 for the above-mentioned hosts, respectively. Among the different organs examined, macroscopic cysts were found to be highest in the oesophagus and the lowest in the heart. Peptic digestion method gave the highest rate (93.3%) followed by indirect fluorescent antibody test (IFAT) (88.6%), squeezing (81.3%), and muscle squash (81.2%). Each infected dog shed a total of about 150-200 million sporocysts. Histologically, developmental stages of the parasite were detected in the small intestinal mucosa of the dogs on Days 7 and 13 post-infection.     

Effects of C/N ratio and periphyton substrates on pond ecology and production performance in giant freshwater prawn Macrobrachium rosenbergii (De Man, 1879) and tilapia Oreochromis niloticus (Linnaeus, 1758) polyculture system

The production performances of giant freshwater prawn Macrobrachium rosenbergii and Nile tilapia Oreochromis niloticus in C/N‐controlled periphyton‐based polyculture systems were evaluated in triplicate. Three different management practices were compared: the traditional practice without addition of periphyton substrates and carbohydrate (Control), addition of maize flour to maintain a carbon: nitrogen rate of 20:1 (treatment CN) and addition of both maize flour and periphyton substrates (treatment CN+P). This experiment used a pre‐optimized stocking density of tilapia and freshwater prawn by Asaduzzaman et al. Aquaculture [286 (2009) 72]. All ponds were stocked with prawn (3 m²) and monosex Nile tilapia (1 m^?2). Bamboo side shoots were posted vertically into the pond bottoms as periphyton substrate covering an additional area of 171 m² for periphyton development. A locally formulated and prepared feed containing 17% crude protein with C/N ratio close to 15:1 was applied twice daily in all ponds considering the body weight of freshwater prawn only. Water quality parameters, except total alkalinity did not vary significantly (P > 0.05) among treatments. Both, organic matter and total heterotrophic bacterial loads (THB) in the sediment were significantly (P < 0.05) higher in treatment CN+P followed by treatment CN and control. Periphyton biomass in terms of dry matter and chlorophyll a values constantly decreased during the culture period. Substrates contributed 66% and 102% higher net yield of freshwater prawn than CN and control treatment respectively.