Holstein Stud Book December 2015

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Proof information explained
Milk, Fat and Protein
The Predicted Transmitting Abilities (PTA’s) are the most
commonly used indices around the globe for comparing the
production traits of sires.
For Example; +300kg Milk, +24.1kg Fat, +20kg Protein,
Rel. 79%
The daughters of this sire would be expected to give on
average, in their first lactation, an extra 300kg of milk,
24.1kg fat and 20kg protein, compared to daughters of
a sire who had a PTA of 0kg Milk, 0kg Fat and 0kg
Protein. The reliability figure is a reflection of the number
of daughters that have contributed to the bull’s proof and
their distribution across herds. When published for bulls,
reliability ranges from 50% to 99%. The higher the
reliability, the more likely the proof is to be an accurate
reflection of the sire’s true transmitting ability.
Note: PTA’s from different breeds and countries should not
be directly compared as the genetic bases will be different.
Linear Pattern
It is not a measure of the sire’s own type, but is calculated
from the linear scores of daughters and how far from the
breed average the daughters score in comparison to their
dams and contemporaries for each trait. The figures are
expressed on a scale of -3 to +3, with both extremes
denoting a likelihood of movement. A few exceptional
animals will fall outside this range. These figures are
known as standard deviations and indicate how far the
animal is from breed average.
Fertility Index
The fertility index is a guide to the fertility of daughters in
a UK herd. As a rough guideline, the scale ranges from
-20 to +20, with the higher values being better. Every +1
increase is predicted to reduce calving interval by half a day. The
proof will read either Non-Improver for scores below -0.5, Average
for scores between -0.4 to -0.01 or Improver
for scores above 0.
Lifespan
The lifespan value is measured by actual daughter
survival and from certain type traits including feet and legs
composite, mammary composite and somatic cell count. The
scale ranges from -1 to +1 with higher values being better.
The proof will read either Non-Improver for negative values, or
Improver for those above breed average. A value of +0.5 means
the daughters of that bull are expected to last 0.5
lactations longer than those from a bull with a value of +0.
Calving Ease
Calving ease is a prediction of how easy a calf by this sire will
be born. The scale runs from -3 to +3. The proof will read, +0.3
or higher as Easy, -0.3 up to +0.2 as Average and any below -0.4
are classed as Harder. For ExcelGen bulls, symbol will
only appear for bulls with UK calvings.
Temperament
Temperament is assessed on all of a sire’s daughters that
are included in a proof. The scale runs between -3 and +3
with below -0.5 reading Below Average, -0.5 to +0.5
Average and over +0.5 Excellent.
Somatic Cell Count
SCC is a measure of a sire’s daughters predicted average
somatic cell score across her lactation. In general the scale
goes from -25 through to +30, with the lower numbers
indicating the lower cell scores. The proof will read
Improver for scores below -5, Average for scores between
-5 and 0, and Non Improver for bulls with values above 0.
Complex Vertebral Malformation (CVM) and Bovine
Leukcyte Adhesion Deficiency (BLAD)
All bulls published in this brochure are free of the genetic
recessives CVM and BLAD.
Brachyspina (BY)
This is often referred to as BY. It can cause abortion and
stillbirths, shortened spinal cord, long legs and abnormal
organs which potentially has a large negative impact on
fertility. It is found in about 6% of the Holstein population and
it is when two copies of this allele are inherited we see serious
or fatal consequences in the resulting embryo. Bulls which have
tested positive for this have ‘BYC’ after the name.
Haplotypes
Recently USDA announced the discovery of three Holstein
haplotypes and three Jersey Haplotypes that appear to cause
embryo loss when they exist in the homozygous state. The three
Haplotypes discovered have not been directly observed and the
exact genetic or biological cause is unknown.
Because of this, they have been given simple names of Holstein
Haplotype 1 (HH1), Holstein Haplotype 2 (HH2) and Holstein
Haplotype 3 (HH3), or JH1, JH2 or JH3 to represent
Jersey Haplotypes. These Haplotypes appear to have a
recessive mode of inheritance where animals with zero or one
copy of the Hapoltype are completely normal. Those that inherit
two copies of the Haplotype are lost as embryos, most likely
early in gestation.
POC - Heterozygous Polled, Polled Carrier or Pp
50 percent of progeny from a heterozygous polled sire will be
polled when mated with a non polled cow.
POS - Homozygous polled or PP
100 percent of progeny from a homozygous polled sire will be
polled when mated with a non polled cow.
* All known bulls which carry recessive genes have been
identified within the brochure.
Milking Speed
The scale runs between -3 and +3, with negative numbers
being slower to milk and positive numbers faster.
The proof will read, below -0.5 as Below Average,
-0.5 to +0.5 as Average and over +0.5 as Fast.
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