Progress 10/01/00 to 09/30/05
Outputs
A trial was conducted in central Arkansas from July 1 to September 30 to evaluate the effects of feeding Tasco Ascophyllum nodosum to high-producing dairy cows during hot weather. The 525 cows were divided in 4 free-stall barns to achieve 2 similar groups of large cows and small cows. Milk yield of cows averaged 28.8 kg/d for control and treatment groups during June, the preliminary period. All cows received a total mixed ration containing either 0 or 0.25% Tasco. Respirations were counted on 60 cows weekly. Cows fed Tasco had fewer respirations per minute on August 3 (77.3 compared to 88.5 for control cows; P < 0.05), on August 10 (80.0 compared to 91.4 for control cows; P < 0.01), on August 31 (66.6 compared to 71.5 for control cows; P < 0.05), and on September 7 (60.6 compared to 68.1 for control cows; P < 0.01). Cows fed Tasco produced more (P < 0.01) milk during July, August, and September; however, there was a significant interaction with size of cows during
August (P < 0.01) and September (P < 0.05) caused by 2.3-kg/d more milk for the larger cows fed Tasco compared to similar yield for smaller cows. Cows were bred, but the number of pregnancies from the larger breeds was very low (3 of 50) for control cows. With Tasco in the diet, the pregnancy rate was enhanced (P < 0.01) dramatically (20 of 55). The number of inseminations per conception and the days open before first service did not vary (P > 0.05) among treatment groups. With Tasco in the diet, respiration rates were reduced for both large and small cows, although the effect appeared dependent upon time.
Impacts
Tasco reduced the steep decline in milk yield in hot weather of the larger cows and dramatically enhanced the pregnancy rate of the larger cows, but smaller cows were not affected.
Publications
- Panivivat, R., Kegley, E.B., Kellogg, D.W., Pennington, J.A. VanDeveder, K., Hellwig, D.H., Wistuba, T.J., and Krumpleman S.L. 2005. Preference for free-stalls bedded with sand or granite fines and changes in bacterial counts in those materials. Professional Anim. Scientist 21:248-253.
|
Progress 01/01/04 to 12/30/04
Outputs
Different types of bedding were studied for calves. Granite fines formed a harder surface (1.5 cm) than sand (2.6 cm), rice hulls (2.1 cm), wheat straw (9.1 cm), or wood shavings (2.1 cm); and calves bedded on granite fines scored the dirtiest (2.0 on a scale of 1 to 4). When bedding materials were evaluated for cleanliness, sand scored the dirtiest while pens bedded with rice hulls, long wheat straw, and wood shavings scored cleaner. Long wheat straw was more absorbent (340.8%) than rice hulls (185%), wood shavings (185%), sand (26.5%), and granite fines (32.5%). On day 0, coliform counts were greatest in rice hulls. After use, coliform counts were greatest in long wheat straw (week by bedding material interaction). On d 42 the concentration of ammonia at 10 cm above the bedding was lowest for long wheat straw (1.1 mg/kg per hour).
Impacts
The cooler bedding (sand) in hot weather is expected to be intermediate in other physical measures.
Publications
- Panivivat, R., Kegley, E. B., Pennington, J. A., Kellogg, D. W., and Krumpelman, S. L. 2004. Growth performance and health of dairy calves bedded with different types of materials. J. Dairy Science 87:3736-3745.
|
Progress 01/01/03 to 12/31/03
Outputs
Bedding temperature in 36 free stalls for lacting cows was measured. Bedding consisted of sand, rice hulls, and a mixture of sand and rice hulls. Additionally, SandTrap (trademark) devices were used to hold bedding in all of the stall or in only one-half of the stall. The air temperature averaged 31.5 degrees C outside and 29.1 degrees C inside the free stall barn. Sand bedding was warmer (P > 0.05) in the front of the stalls when the entire SandTrap (trademark) was used (30.4 vs. 31.8 degrees C), but bedding temperatures at the back of stalls did not differ between use of one-half and entire SandTrap (trademark) devices. Cows preferred the full SandTrap (trademark) compared to the one-half device. Sand was superior to rice hulls as a bedding material because sand remained in stalls and had lower bacterial counts than rice hull bedding.
Impacts
Providing dairy cattle with a cooler and healthier enviornment (bedding) to enhance milk production during hot weather conditions.
Publications
- No publications reported this period
|
Progress 01/01/02 to 12/31/02
Outputs
Dairy farmers with free stall barns need a better bedding material for cows. While river sand is the material of choice, it causes problems in drain systems and lagoons. To relieve the environmental problem granite fines, produced to manufacture asphalt shingles, were considered in a research trial at Ark-Tenn Dairy Research and Development Center. The preference of cows for the different beddings was studied, and bacterial counts were made in the different bedding materials. When granite fines were used in free-stalls, the material packed harder than sand. Cows were 2.8 times more likely to choose a stall with sand than with granite fines. Once in the stall, the cow was lying on sand more than on granite fines. Absorbency of the materials was similar. Although, initially there were more bacteria in sand, the total bacteria counts did not differ one day after cows were using the material. Coliform counts were similar, but Klebsiella spp. was increased in the stalls
bedded with granite fines. The differences indicated that cows preferred to lie on the softer bedding material (sand), and stalls bedded with sand tended to have lower bacterial counts. Granite fines are less expensive than sand, but the material packs harder than sand in cattle stalls. That characteristic might keep the granite fines in the stall for a longer period of time and prevent unwanted accumulation in drains and lagoons. However, cows clearly preferred the softer material. There is no compelling reason to recommend that farmers change from sand to granite fines.
Impacts
Granite fines are less expensive than sand, but the material packs harder than sand in cattle stalls. That characteristic might keep the granite fines in the stall for a longer period of time and prevent unwanted accumulation in drains and lagoons. However, cows clearly preferred the softer material. There is no compelling reason to recommend that farmers change from sand to granite fines.
Publications
- Panivivat, R., Keley, E.B., Kellogg, D.W., Pennington, J.A., VamDeveder. K., Hellwig, D.H., Wistuba, T.J., and Krumpelman, S.L. 2002. Preference for and bacterial counts in sand and granite fines as bedding for lactating cows. University of Arkansas Agric. Exp. Sta. Res Series 499. Pages 143-146.
|
Progress 01/01/01 to 12/31/01
Outputs
Until recently there has been limited interest in crossbreeding dairy cattle because of the excellent success of selecting for milk production within the breeds. However, traits such as breeding efficiency have not responded as positively to additive genetic selection. Jersey cattle have maintained breeding efficiency better than Holsteins and are recognized as more heat tolerant than other dairy breeds. Growth, luteal activity, and pregnancy rates were evaluated in 89 dairy heifers raised as contemporaries. Breed types were Holstein (H, n = 35), Jersey x H (JH, n = 30) and Brown Swiss x H (BSH, n = 24); they ranged in age from 129 to 205 d at the beginning of the trial. At approximately 12 mo of age, two blood samples for each heifer were collected (10 d apart) by jugular vein puncture for progesterone assay. Heifers were considered cycling if progesterone concentrations were ,d1 ng/ml in either of the two serum samples. Heifers were bred artificially after
synchronizing estrus starting at 14 mo of age, and pregnancy status was determined ultrasonically 60 d after breeding. The BSH and H had similar (P > 0.05) weights and hip heights; but JH were lighter and shorter (P < 0.05). No differences (P > 0.05) occurred for depth of chest and mean BCS. Estrus occurrence by 12 mo of age was greater (P < 0.05) for JH (90%) than for BSH (75%) and lowest (P < 0.05) for H (47%). Pregnancy rates did not differ (BSH = 96%, JH = 87%, H = 77%). These data suggest that genetic effects of crossbreeding influence early growth and cyclicity at 12 mo of age for replacement dairy heifers.
Impacts
(N/A)
Publications
- A.H. Brown, Jr., Kellogg, D.W., Johnson, Z. B., Rorie, R.W., Coblentz, W.K., Sandelin, B.A. and Lesmeister, K.E. 2001. Growth, Luteal Activity, and Pregnancy Rates of Three Breed Types of Dairy Heifers in a Forage-Based Development Program. Professional Anim. Scientist 17:20-26.
|
|