paklive.gms : Pakistan Punjab Livestock Model
This model examines the role of livestock in the agricultural
sector in the Punjab and how it is effected by variations in
farm size, water availability, credit, crop prices and labor.
Reference:
- World Bank, Pakistan Punjab Livestock Project. Tech. rep., The World Bank, 1977.
Small Model of Type: LP
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$Title PAKLIVE: Pakistan Punjab Livestock Model (PAKLIVE,SEQ=55)
$Stitle Set Definitions
$Ontext
This model examines the role of livestock in the agricultural
sector in the Punjab and how it is effected by variations in
farm size, water availability, credit, crop prices and labor.
World Bank, Pakistan Punjab Livestock Project. Tech. rep., The World Bank,
1977.
$Offtext
Set c crops / wheat
basrice
irrrice irradiated rice
maize
oilseed
gram
cotton
sugar
berseem
kharfodder /
h livestock types / bullocks , bufflocows , cattlecows /
f seasonal inputs / landuse
irrwat irrigation water
labor
tdn total digestible nutrients
protein
draftpower
credit /
n(f) nutrients / tdn , protein /
dp(f) draftpower / draftpower /
ta seasons and annual / annual , kharif , rabi /
t(ta) seasons / kharif , rabi /
Scalar fsize farm size (acres) / 12.5 /
watercost cost of purchased water (rs per inch) / 20 /
laborcost cost of hired labor (rs per man-day) / 10 /
maxcredit maximum annual credit (rs) / 20000 /
lrr livestock reproduction ratio / 1.25 /
wpup maximum water purchaseable (inches) / 17.5 /
draftcost cost of hired draftpower (rs per workday)/ 30 /
Parameter bullockr(c) bullock requirements in the third season (work-days) / wheat 8, oilseed 2, sugar 1, berseem 2/
bullocka(h) livestock availability in third season (work-days) / bullocks 40 /
waf(t) maximum water available at no cost (inches per acre) / kharif 56 , rabi 32 /
rationcost(n) cost of purchased rations (rs per kg) / tdn 1.3 , protein 5 /
cprice(c) crop prices (rs per maund) / wheat 41.15, basrice 89.38, irrrice 39.92, maize 37.04
oilseed 59.26, gram 37.04, cotton 127.27, sugar 5.96 /
gmargin(h) gross margin from livestock (rs) / bufflocows 900 , cattlecows 600 /
eff(n) storage efficiency of nutrients / tdn .5 /
maxflab(t) maximum seasonal family labor (man-days) / kharif 390 , rabi 530 /
watavail(t) max water available on farm at no cost (inches)
crev(c) crop revenue (rs per acre)
Table cinput(*,ta,c) input-output matrix for crops
* landuse : acres
* irrwat : inches
* labor : man-days
* draftpower: work-days
* tdn : kgs
* protein : kgs
* credit : rs per year
* yield : maund/acre per year
wheat basrice irrrice maize oilseed gram cotton sugar berseem kharfodder
landuse.kharif .1 1. 1. 1. .3 .3 1. 1. .3 1.
landuse.rabi 1. .1 .6 1. .4 1. .8 .1
irrwat.kharif 65. 60. 25. 30. 25. 15.
irrwat.rabi 20. 20. 15. 10. 45. 35.
labor.kharif 7. 21. 21. 22. 4. 2. 11. 15. 3. 18.
labor.rabi 16. 9. 9. 5. 10. 8. 10. 62. 15. 6.
tdn.kharif -530. -510. -450. -60. -350. -2400.
tdn.rabi -450. -650 -85. -215. -130. -1775. -1940.
protein.kharif -6. -8. -31. -1. -6. -242.
protein.rabi
draftpower.kharif 12. 8. 8. 3. 3. 3.
draftpower.rabi 6. 1. 1. 7. 1. 3. 7. 30. 6.
credit.annual 150. 180. 220. 100. 120. 70. 145. 500. 65. 120
yield.annual -16 -11.4 -21 -10 -6 -6 -10 -375
Table linput(*,ta,h) livestock inputs-outputs
* labor : man-days
* draftpower : work-days
* tdn : kgs
* protein : kgs
* credit : rs per year
bullocks bufflocows cattlecows
labor.kharif 17.5 19 14
labor.rabi 26.5 29 21.5
draftpower.kharif -100
draftpower.rabi -175
tdn.(kharif,rabi) 1550 1050 750
protein.(kharif,rabi) 155 105 75
credit.annual 300 250 180
;
crev(c) = - cprice(c)*cinput("yield","annual",c);
watavail(t) = fsize*waf(t);
Display crev,watavail ;
$Stitle model definition
Positive variables xcrop(c) cropping activities (acres)
wpurchase(t) water purchased (inches)
xrations(n,t) purchased rations (kg)
xlabor(t) hired labor (man-days)
xtransf(n,t) fodder transfer (kgs)
dhire hire of draftpower (workday)
xlivestk(h) livestock production (animals)
Variable rev revenue from livestock and crops (rs)
lcost cost of hired labor (rs)
dcost cost of hired draftpower (rs)
wcost cost of purchased water (rs)
rcost cost of purchased rations (rs)
return net return
Equations draft(dp,t) draftpower constraint (work-day)
land(t) land use by season (acre)
water(t) irrigation water use by season (inches)
labor(t) total labor required by season (man-day)
nutbal(n,t) seasonal purchase of nutrients (kgs)
bullock bullock use during third season (work-days)
credit credit requirements (rs)
totalrev total revenue from crops and livestock (rs)
costlabor cost of hired labor (rs)
costdraft cost of hired draftpower (rs)
costwater cost of purchased water (rs)
costrat cost of purchased rations (rs)
obj net return (rs);
totalrev.. rev =e= sum(c, crev(c)*xcrop(c)) +sum(h, gmargin(h)*xlivestk(h));
costdraft.. dcost =e= draftcost*dhire;
costlabor.. lcost =e= laborcost*sum(t, xlabor(t));
costwater.. wcost =e= watercost*sum(t, wpurchase(t));
costrat.. rcost =e= sum(n, rationcost(n)*sum(t, xrations(n,t)));
obj.. return =e= rev - lcost - wcost - rcost - dcost;
land(t).. sum(c, cinput("landuse",t,c)*xcrop(c)) =l= fsize;
water(t).. sum(c, cinput("irrwat",t,c)*xcrop(c)) =l= watavail(t) + wpurchase(t);
labor(t).. sum(c, cinput("labor",t,c)*xcrop(c)) + sum(h, linput("labor",t,h)*xlivestk(h)) =l= maxflab(t) + xlabor(t);
draft(dp,t).. sum(c, cinput(dp,t,c)*xcrop(c)) =l= - sum(h, linput(dp,t,h)*xlivestk(h));
bullock.. sum(c, bullockr(c)*xcrop(c)) =l= sum(h, bullocka(h)*xlivestk(h)) + dhire;
credit.. sum(c, cinput("credit","annual",c)*xcrop(c)) + sum(h, linput("credit","annual",h)*xlivestk(h))
+ rcost + lcost + wcost + dcost =l= maxcredit;
nutbal(n,t).. - sum(c, cinput(n,t,c)*xcrop(c)) + eff(n)*xtransf(n,t--1) + xrations(n,t)
=g= sum(h, linput(n,t,h)* xlivestk(h));
xcrop.up("sugar") = 2 ;
wpurchase.up(t) = wpup ;
Model pakistan / all /;
Solve pakistan using lp maximizing return;
Parameter ivl imputed value of family labor (rs);
ivl= rev.l / sum (t, sum(c, cinput("labor",t,c)*xcrop.l(c))+sum (h,linput("labor",t,h)*xlivestk.l(h)) );
Display ivl;
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