MHB Calc Male & Female Cattle Pop Growth Rates: 30 Heifers, 100% Fert/Surv

AI Thread Summary
The discussion focuses on estimating male and female cattle population growth rates from an initial stock of 30 heifers, considering factors like age at first mating and calf birth intervals. It assumes 100% fertility and survival, with calves being evenly split between genders. The user seeks assistance in formulating the growth rates for both male and female populations over five and ten years. Despite expressing initial interest in collaboration, the user indicates they have resolved their calculations manually and no longer require help. The user appreciates the forum's potential value and plans to return in the future.
audax1
Messages
2
Reaction score
0
I want to estimate the number of male and female cattle produced over a period of time (say, five years and ten years) from an initial stock of 30 heifers, all 18 months of age at which age they are first joined (mated). Assume that the first calf is born when the mother is 27 months old. Thereafter, a new calf is born every two years. Assume also 100% fertility and survival, new-born calves are 50% male, 50% female and all females are joined at 18 months.

If all calves were female, a birth every two years would be a population growth rate of 50% pa and the calculation would be simple but I don't know how to devise the formulae for female population growth rate and male population growth rate. Can you help?
 
Mathematics news on Phys.org
It appears that nobody is interested in this topic so I'll close it down. I actually have a much more complicated scenario than I've described and I worked it all out manually so I now don't need any help.

But this looks to be a really useful and interesting site. I'm sure I'll be back.
 

Thread 'Non-orthogonal bases'

Suppose ,instead of the usual x,y coordinate system with an I basis vector along the x -axis and a corresponding j basis vector along the y-axis we instead have a different pair of basis vectors ,call them e and f along their respective axes. I have seen that this is an important subject in maths My question is what physical applications does such a model apply to? I am asking here because I have devoted quite a lot of time in the past to understanding convectors and the dual...
View full post »

Thread 'Fermat's Last Theorem'

Fermat's Last Theorem has long been one of the most famous mathematical problems, and is now one of the most famous theorems. It simply states that the equation $$ a^n+b^n=c^n $$ has no solutions with positive integers if ##n>2.## It was named after Pierre de Fermat (1607-1665). The problem itself stems from the book Arithmetica by Diophantus of Alexandria. It gained popularity because Fermat noted in his copy "Cubum autem in duos cubos, aut quadratoquadratum in duos quadratoquadratos, et...
View full post »

Thread 'What Exactly is Dirac’s Delta Function? - Insight'

Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. In Dirac’s Principles of Quantum Mechanics published in 1930 he introduced a “convenient notation” he referred to as a “delta function” which he treated as a continuum analog to the discrete Kronecker delta. The Kronecker delta is simply the indexed components of the identity operator in matrix algebra Source: https://www.physicsforums.com/insights/what-exactly-is-diracs-delta-function/ by...
View full post »

Similar threads

MHB Population formula part 1: Birth
Replies
2
Views
2K
News ROFLMAO happy new year from bill blum
Replies
10
Views
3K

Hot Threads

Recent Insights

Back
Top