Goat as a livestock enterprise
As ruminants, goats are able to graze, and to benefit from natural pastures, or by- products. They are easy to handle and suitable to very small farms or rural households; however, more sensitive to predators than cattle. As milk producers, they are less competitive than improved dairy cattle, and as meat producers they are less competitive than pork and poultry. Therefore, goat production can survive only if they can be fed mostly with low cost forage on natural pasture in large flocks, where free range is available and safe, or on by-products in small flocks belonging to small farmers. And finally if there is a demand for their product at higher prices than similar products, and this demand can be met by appropriate marketing channels.
Demand for goats is on the rise
According to recent USDA statistics, there has been an influx of immigrants into the southern region of US. Hispanic people (14 million in the US) and Muslims (at 6 million, they represent the largest minority religion in the US) make up significant communities in large urban areas of AL, FL, GA, MS and TN. The growth in this population sector is expected to continue through the year 2050, and the growth in the five above-mentioned states is expected to far exceed the national average. This can be partially attributed to the jobs available in poultry, forestry, and horticultural operations, as well as the vegetable and fruit industries in this region. This population shift has impacted local and national demand for goat meat, and a dramatic increase in goat production. Despite this increase in production, processors of goat meat cannot get an adequate supply of quality goats. Consequently, current assessments and future projections suggest a considerable opportunity for goat production by limited resource farmers.
Research support is limited
The Alabama Department of Agriculture and Industries has, for the first time, hired personnel to monitor, record and distribute a weekly market report for goats in Alabama. Despite this interest in goat production, local and national research support is lacking for this rapidly growing sector of agriculture. Feed costs are the largest single variable cost in any livestock operation. Therefore, minimizing feed cost can improve profitability of the farm. Use of quality germplasm to improve herd performance is another key to profitability. Animal health greatly influences reproductive success and weight gains, two key aspects of successful livestock production Goat research at Tuskegee University among other projects has focused on alternative feed sources such as broiler litter, whole cottonseed, and other by-products and specific trace mineral (Cu) to reduce the feed cost and improve efficiency of gain in goats.
Summary of latest goat research at Tuskegee University
Research at Tuskegee University is carried out by graduate students and their professors as part of the required work to fulfill the requirement for the Master of Science Degree in Animal & Poultry Sciences. Following research was directed by Dr. Sandra Solaiman as a part of the required work for M.S. Degree for Ms. Carla Hopkins
Effect of high dietary Cu on performance and
carcass characteristics in goat kids
Dr. Sandra G. Solaiman, Major Professor and
Ms. Carla Hopkins, Graduate Student
Fifteen Boer x Spanish mixed goat kids were used in a study to determine the effect of high dietary Cu on growth performance and carcass characteristics. The copper sulfate (CuSO4, 5H2O) supplementation consist of 0 mg Cu/day as a control group, 100 mg Cu/day and 200 mg Cu/day. Animals were fed twice a day a 70:30 grain:hay ration free choice, to meet daily requirements of growing kids. Feed intake and refusals were monitored daily and intake was adjusted weekly. Body weight, respiration rate, heart rate and rectal temperature were recorded every two weeks throughout the study. Blood and fecal samples were collected every two weeks and analyzed for Cu concentration. Blood samples were collected at the end of the study and analyzed for sorbitol dehydrogenase activity (an enzyme that can indicate liver damage or Cu toxicity). Individual goat average daily gain, average daily feed intake, percent dry matter of grain consumed, gain efficiency ratio and cost efficiency were calculated for performance periods ( 70 days period). Animals were harvested and hot carcass weight, cold carcass weight, 12th rib backfat, body wall fat, adjusted fat thickness, kidney-pelvic fat, longissimus muscle area and carcass shrinkage were measured. Percentage of boneless closely trimmed retail cut was calculated using a regression formula for lambs. Carcass composition was measured for moisture protein, fat, and ash in the 9-10-11 rib section and in one half the whole carcass. Liver, bile, longissimus muscle and kidney samples were obtained postmortem and analyzed for Cu concentration. Regression equations were computed for predicting whole body composition using carcass measurements and 9-10-11 rib section composition percentages.
Respiration, heart rate and rectal temperature were not affected by feeding supplemental Cu. Serum Cu was maintained within the normal range for all goats receiving supplemental Cu when compared to the control group.
Initial BW for the performance period were not different between groups. Average daily gain was higher (147 g/day) when animals receive 100 mg Cu, compared to 131 and 116 g/day for control and 200 mg Cu group. Average daily feed intake decreased as Cu supplementation increased, with the control group consuming a higher grain: hay ratio (80:20) in the diet over the 100 mg or 200 mg Cu group. Gain efficiency was higher in the 100 mg Cu group with the control and 200 mg Cu group having similar ratios. The cost efficiency improved and the cost of production was lowest in the 100 mg Cu group when compared to the control and 200 mg Cu groups.
The live/harvest selection criteria placed the control and 100 mg Cu group in the selection criteria No. 1 and the 200 mg Cu group in the selection criteria No. 2. No differences were observed in hot carcass weight, chilled carcass weight or carcass shrinkage in this study, however, dressing percent was lower in the 200 mg Cu group. Backfat over the 12th rib and adjusted fat thickness decreased as Cu supplementation increased. Body wall fat measured lowest in the 100 mg Cu group. The reduction in backfat is consistent among studies conducted in cattle fed supplemental Cu. There was no difference in kidney-pelvic fat or longissimus muscle area. The percent boneless closely trimmed retail cuts improved as Cu supplementation increased.
The moisture, protein and ash percent of the 9-10-11 rib section increased linearly as Cu supplementation increased. The fat percent of the 9-10-11 rib section decreased as Cu supplementation increased. Chemical analyses of the one half of the whole body resulted in similar trends as reported for the 9-10-11 rib section analyses.
Liver Cu concentrations increased as Cu supplementation increased, however kidney and bile Cu concentrations did not differ among treatment groups. The level of Cu increased in the feces as the supplementation of Cu increased.
In general, the present study indicated that Boer x Spanish mix goat kids could benefit from receiving copper supplementation over the presently established required amount of 8 - 10 ppm. However, when copper is supplemented above the animal's threshold reductions in performance and carcass measurements occur. Further research is needed to determine copper concentrations that can optimize animal performance and lipid and cholesterol metabolism.. Further research is also needed to establish the proper requirements of supplemental copper to administer at different phases of the growth period and different production stages in the goat. Copper effects as influenced by age, breed, genotype and diet need to be investigated in relation to performance and carcass characteristics in goat. Studies need to be conducted with larger goat numbers to establish a simple method in determining the carcass composition of goats.
Thanks to Dr. Sandra Solamain for her work in this field and for submitting this paper.
Dr. Solaiman may be contacted at firstname.lastname@example.org or at her Tuskegee e-mail email@example.com