the effect of individual parameter

[Barkamih]

proc nlin data = new outest=ESTIMATES;
parms A = 15 B = 0.19 C = -0.0012 ;
bounds  A B C > 0; 
by cow_id;
model  TEST_DAY_MILK_KG = A * Time **b * exp(-C*Time);
output out = Fit predicted = Pred ;
run;
proc sql;
create table persistency as
select 
    cow_id,
    A, B, C, 
    -(B+1)*LOG(C) as P,
	A * (B/C)**(B) * exp(-B) as peakYield
from ESTIMATES
where _TYPE_ = "FINAL";
select * from persistency;
run;
quit;

Hi Guys 

could you please help me to find out the solution to this question  

I would like to know how to find the effect of environmental factors by using the individual parameter estimates from this code above. 

Note: the environmental factors are e.g  (parity, calving month ...... .) 

in this case what the next step I might do to get this answer. 

if you looking for more information about my study please let me know 

kind regards 

Ibrahim