corn as the energy source since the limiting factor is dry matter in-
take. Dry matter intake may have been the limiting factor in
these cows since they were on a full feed of guinea grass pasture
prior to pellet feeding.
 Phosphorus was also determined to be a deficiency in the dry
cow ration since these animals were not given any mineral or
pelleted feed. The guinea grass pasture was shown to be deficient
in phosphorus as well as calcium, protein, energy and total
digestible nutrients (Table 2).
 Recommendation was given to feed 8 lbs of the complete pellet
to the dry cows on pasture to correct the energy and phosphorus
deficiency.


 TABLE 1. Lactation ration.

 1000 lbs TDN(lb) Net Energy Protein Ca(lbs) Phos(lbs)
 Maintenance 7.5 8.3 1.3 .04 .03
 50 lbs 4% Milk 16.5 16.5 3.9 .14 .1
 24.0 24.8 5.2 .18 .13

 50 Ibs grass
 35% dry matter 8.5 5.74 1.2 .013 .012
 -15.95 -20.06 -4.1 -.165 -.111
 25 lbs pellet 20.5 19.75 5.5 .5 .2
 +4.55 -.31 +1.4 +3.35 +.089
 requirement/10 Ibs
 milk over 50 ibs 3.05 3.1 .74 .026 .019




 TABLE 2. Dry cow requirement (last 2 months of pregnancy).

 Net Energy Protein
 1320 lbs TDN(lb) Kcal (Ibs) Ca(lbs) Phos(lbs)
 Maintenance
 & pregnancy 12.3 13.5 1.6 .07 .06
 50 lbs 35% DM
 guinea grass 10.8 7 1 .06 .03
 Deficit -1.5 -6.5 -.6 -.01 -.03
 8 lbs pellet/day 6.6 6.34 1.8 .16 .06



 Reproduction problems were apparent in all five herds exam-
 ined. Fertility examination of the holstein bulls used in the
 breeding programs revealed a serious deficiency in sperm quality
 of most of the bulls (Cates et al., 1976). The etiology was com-
 plex in nature. The scrotal size was adequate and the libido was
 good, but the sperm cell concentration, motility and morphology
 were seriously deficient in most of the holstein bulls. In contrast,
 most of the senepol bulls examined had excellent semen quality.
 It was very obvious that a breed difference exists in terms of adap-
 tation and nutritional efficiency between the holstein and the
 senepol breeds since the two breeds were used in an identical
 manner in regard to nutrition and breeding environment. The
 holstein bulls were being used in pasture mating situations
 without grain or supplement feeding. They obviously could not
 successfully breed cows continually without rotation and rest.
 They also required additional nutrients and energy.
 The infertility in the cows was caused in part by nutritional
 deficiency, especially phosphorus deficiency. Deficiency in
 phosphorus has been shown to cause infertility as exhibited by re-
 tained placenta, metritis, repeat breeders, and anestrus. The in-
 fertility in these herds, as exhibited by repeat breeding and
 metritis, caused the bulls to work excessively hard due to the large
 numbers of females returning to estrus instead of becoming preg-


nant. The breeding failures compounded the fertility problems
of the holstein bulls who were marginally fertile due to inade-
quate nutrients (Morrow, 1980, 1969).
 Leptospira harjo was incriminated in infertility in one of the
herds. Serological tests revealed high titers to this organism
(1:800) in several cows who were showing clinical signs of early
embryonic death and repeat breeding. These animals were not
vaccinated with Leptospira vaccine. Therefore, although the
single high titer is not conclusive, it is good evidence of an ongo-
ing infection with this organism. Vaccination programs were ad-
vised to correct the problem (Hanson, 1980).
 Herd health program changes were recommended by the
visiting consultant to comprehensively deal with the multifaceted
dairy production problem in the dairies of St. Croix. They are as
follows:
Reproduction:
 1. Veterinary examination at two to four week intervals.
 2. Cows to be examined:
 a. All open cows once/month.
 b. Examine for pregnancy at 35 days post-breeding and re-
 examine at 70-90 days of pregnancy.
 c. All problem cows; e.g. metritis, pyometra, cystic ovaries.
 d. All post-partum cows 15-30 days post-calving.
 3. One fertile bull/25 open cows.
 4. Individual cow records-written or computer.
 5. Fertility check bulls prior to first use and annual recheck.
 6. Culture all bulls for Vibrio fetus and Trichomonas.
 7. Initiate artificial insemination using positive P.D. holstein
 bulls on all cows the first 90 days of lactation or first 3
 breeding.

Immunizations:
 1. Leptospirosis- 5-way vaccine to all breeding animals 12
 months and older. Vaccinate all breeding animals in-
 cluding bulls annually.
 2. Infectious Bovine Rhinotracheitis annual to all animals
 beginning at five months of age.
 3. Vibriosis-twice to heifers prior to breeding age and to all
 breeding animals annually.
 4. Optional- Bovine Virus Diarrhea and Clostridium vaccine.


Nutrition:
 1. Feed and forage analysis four times/year.
 2. Eighty grams phosphorus intake/lactating cow/day.
 Forty grams phosphorus intake/dry cow/day.
 3. Challenge feed the high producing cows for the first 90
 days of lactation -2.5 lbs corn or corn equivalent for 5 lbs
 milk.
 4. Good quality mineral mix with Se added fed free choice to
 all animals on pasture including bulls.
 5. Supplement all growing and breeding bulls with 5-8 lbs/
 day of complete pelleted feed or grain with mineral.


Parasite Control
 1. Dip or spray for external parasites every 2-4 weeks depend-
 ing on season or chemical.
 2. Deworm all young animals every three months.


Mastitis Control:
 1. Dry cow treatment at dry off time.
 2. Teat dip after milking.
 3. Use individual towels.
 4. Use strip cup prior to milking.
 5. Equipment evaluation every six months-vacuum test,
 liners and pump.
 6. Somatic cell count of bulk tank monthly.


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