Modifying the acute phase response of Jersey calves by supplementing milk replacer with omega-3 fatty acids from fish oil.

Fifty-one Jersey bull calves (5 +/- 1 d old) were assigned to 1 of 3 milk replacers to determine the effects of increasing doses of n-3 fatty acids from fish oil on the acute phase response after an endotoxin challenge. All calves were fed a 22.5% crude protein and 18% lipid milk replacer (Calva Products, Acampo, CA) supplemented with an additional 2% fatty acids. Treatments differed only in the supplemental lipid source and included a 3:1 mix of corn and canola oils, a 1:1 blend of fish oil (Omega Proteins, Houston, TX) and the 3:1 mix of corn and canola oils, and fish oil only. On d 23, each calf was injected subcutaneously with 4 microg/kg of body weight of Salmonella Typhimurium endotoxin. Clinical, hematological, and biochemical parameters were measured at 0, 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 18, 24, and 72 h post endotoxin challenge. Endotoxin caused a dramatic rise in respiratory rate; feeding fish oil significantly attenuated the increase. Heart rate and rectal temperature were not affected by treatment. Feeding fish oil attenuated the change in serum iron concentration over time. Endotoxin caused severe hypoglycemia, reaching a nadir at 4 h. Calves supplemented with fish oil had reduced concentrations of serum glucose for 8 to 24 h. Furthermore, calves supplemented with fish oil alone had reduced serum insulin at 12, 28, and 24 h. In contrast, endotoxin caused an acute increase in blood urea nitrogen and nonesterified fatty acids; there were significant linear effects of fish oil on both blood urea nitrogen and nonesterified fatty acids. Serum triglycerides were elevated beginning at 12 h after the endotoxin challenge and returned to baseline values within 72 h. Fish oil suppressed the rise in triglycerides during this period, and the effect was linear with increasing fish oil. Serum concentrations of leptin decreased after the endotoxin challenge; however, the treatment did not influence the response. There was no treatment effect on serum aspartate aminotransferase or lactate dehydrogenase activity. Adding fish oil to milk replacer attenuated many aspects of the acute phase response, and the effect was linear in the range of 5 to 10% of the lipid replaced as fatty acids from fish oil. Adding fish oil might provide a better balance between a necessary versus an excessive acute phase response.

The relationship between linear type traits and fertility traits in high-yielding dairy goats.

Reproductive data collected from 13 medium-size goat farms in central Mexico (582 goats), were used to investigate if linear type traits influenced reproductive performance of high-yielding dairy goats. Data were analysed using multiple stepwise forward logistic regressions. Goats with the higher scores for strength were 1.43 times more likely (p < 0.05) to have larger litters (1.49 vs 1.39) than goats with lower strength. Goats approaching level rump angles were 1.68 times more likely (p < 0.01) to have larger litters, compared with goats with extremely sloped rump angles (1.48 vs 1.37). Goats with rear legs nearly straight (posty) in hock tended (p < 0.08) to presented larger litters than goats with rear legs slightly angled (sickled) in hock (1.49 vs 1.38). Less pronounced rump angle was favourable associated (p < 0.05) with litter weight (4.88 vs 4.53 kg) compared with goats with low pin bones. Goats with poorer udder texture were 1.42 more likely (p < 0.05) to have heavier litters than goats with good udder texture. Goats with faulty mammary system tended (p < 0.07) to have heavier litters than goats with good mammary system. Increasing udder height was associated (p < 0.05) with increasing number of services per conception. Goats with good fore udder attachment and non-refined heads were at reduced risk (p < 0.05) for stillbirths. Goats with stronger median ligament were 65% less likely (p < 0.05) to lose their foetuses than those with looser udder support. Our findings indicate that a greater litter size and litter weight is expected in goats as rump angle becomes less sloped. This study showed that a relationship exists between strength of goats and litter size, and that some traits linked to high milk yield were antagonist to some reproductive traits.

Serum igG, blood profiles, growth and survival in goat kids supplemented with artificial colostrum on the first day of life.

The objective of this study was to compare serum IgG concentrations, blood metabolites indicative of nutritional status, weight gain and mortality rate in goat kids fed a commercial colostral supplement containing immunoglobulins against several pathogen microorganisms, prior to the ingestion of the mother colostrum, and goat kids ingesting natural colostrum only. There was no difference in serum IgG concentrations between 27 kids fed a colostrum supplement (20 g, derived from cow lacteal secretions) prior to the kids' first meal (658+/-703 mg dl(-1)) and 21 kids ingesting maternal colostrum freely (1011+/-1140 mg dl(-1)) at 24 hours of birth. Hematocrit values, serum glucose and urea concentrations at 24 hours and 5 days of age were unaffected by treatment. Serum total proteins were 14% higher (P<0.05) in the unsuplemented group than in the supplemented group at 5 d of age. There was no significant difference between the supplemented and unsupplemented kids in daily weight gain from birth to 70 days of age (92+/-4.8 vs 102+/-5.1 g day(-1)). Mortality was 4% for kids receiving the colostrum supplement as compared with 0.0% for kids ingesting maternal colostrum only. Results suggest that, in intensively managed non-dairy goats with kiddings in summer, the supplementation of this commercial colostrum derived from cow lacteal secretions and containing antibodies against diverse pathogens organisms did not enhanced growth, survival or immunity under the farming conditions of this study.

Influence of tannic acid application on alfalfa hay: in vitro rumen fermentation, serum metabolites and nitrogen balance in sheep.

Alfalfa protein is poorly utilised by ruminants due to its rapid degradation in rumen. The objective of the study was to assess the influence of spraying tannic acid (TA) on chopped alfalfa hay on in vitro rumen fermentation and nitrogen (N) retention by sheep. Alfalfa hay with and without TA was fed to sheep to determine nutrient digestibility and N balance. TA was sprayed on chopped alfalfa at three concentrations to determine its effect on in vitro fermentation of dry matter (DM) and N balance in sheep. Final TA concentrations were 0, 30, 60 and 90 g TA per kg DM. The control was sprayed with the same amount of water but without TA. In vitro DM degradation and the production of gas, ammonium-N (NH4-N) and short-chain fatty acid (SCFA) were measured. TA-sprayed alfalfa and the control were fed to sheep to determine nutrient digestibility and N retention. Addition of TA had no influence on the extent and rate of gas production but significantly decreased NH4-N concentration at 30 (P < 0.05), 60 and 90 (P < 0.0001) g/kg DM. Addition of polyethylene glycol (PEG) to TA-sprayed alfalfa increased NH4-N to a level comparable to non-TA-sprayed alfalfa. Spraying of alfalfa with TA significantly decreased (P < 0.05) isovalerate but did not affect the total and individual SCFA acid production. Tannic acid significantly (P < 0.05) reduced in vitro true degradability of DM (IVTD) after 24 h incubation at levels of 60 and 90 g TA per kg DM. Neutral-detergent fibre digestibility (dNDF) after 24 h (P < 0.01), 60 and 90 (P < 0.0001) g TA per kg DM. The effect of TA on either IVTD or dNDF was not significant (P > 0.05) after 48 h of incubation. There was a strong linear relationship between percentage increase in gas production due to PEG and protein precipitation capacity (R2 = 0.94). N digestibility was significantly reduced with all three levels of TA additions. However, the proportion of urine-N to total N output was reduced by adding 60 g (P < 0.05) and 90 g (P < 0.01) TA per kg DM. Serum metabolites and liver enzymes were not affected by TA (P > 0.05). Higher faecal N as the TA level increased indicates incomplete dissociation of tannin-protein complexes post ruminally. Factors affecting dissociation of tannin-protein complexes need further study.

Biologically based coefficients for partitioning lamb and wool production costs.

Global competition for selling lamb and wool requires sheep producers to effectively prioritize wool and lamb production. Both products are produced simultaneously, and this makes it difficult to differentially assess costs and net returns. This study addressed this issue by developing coefficients for use in financial analysis of lamb and wool profitability across and within five regions of the United States (Eastern, Midwestern, Intermountain West, Great Basin, and Texas). A procedure was developed using a sheep simulation model to partition the amount of nutrients used for lamb and wool production and then using the partitioning information to determine the proportion of costs to be assessed to lamb and wool production. Blackface breed types, when managed without nutritional limitations, had lamb and wool coefficients of .90 and .10, respectively. Wool breeds with unlimited and limited nutrition had lamb coefficients between .80 and .20 and .60 and .40, respectively. In-depth analysis of the Great Basin system indicated that wool and its improvement may contribute as much, if not more, under certain pricing conditions, as increased prolificacy to enterprise profitability. With low lamb prices ($1.32/kg) and moderate wool prices, the partial net returns for a Merino x Rambouillet were higher than the tested prolific breed type ($13.85 vs $11.27/ewe, respectively). This ranking was reversed under high ($2.31/kg) lamb prices ($47.90 vs $55.22, respectively). The derived method provides a basis for analyzing, comparing, and making management and breeding objective decisions.

Aspirin therapy: optimized platelet inhibition with different loading and maintenance doses.

Inhibition of cyclooxygenase by aspirin has been shown to be beneficial in clinical situations such as acute myocardial infarction or unstable angina. The precise effect of various doses of aspirin on acute and long-term inhibition of platelet aggregation and thromboxane synthesis remains unclear. In this study we evaluated the effect of oral aspirin (0, 40, 100, 300, or 500 mg) as the initial loading dose in combination with different maintenance doses of aspirin (0, 40, or 100 mg/day) for 14 days on platelet function in healthy men. Bleeding time 2 or 24 hours after the first aspirin administration was significantly increased for 300 and 500 mg aspirin (p < 0.01). Two hours after the first administration of 100, 300, and 500 mg aspirin, a significant inhibition of collagen-induced platelet aggregation (ED50 collagen: from 3 +/- 1 to 17 +/- 2, 24 +/- 3, 22 +/- 3 micrograms/ml, respectively) was seen. At the same time serum thromboxane B2 synthesis was inhibited by more than 99% with 300 and 500 mg aspirin. At the end of the 14-day observation period, bleeding time was significantly prolonged for the different combinations of aspirin doses compared with initial values (p < 0.01). Collagen-induced platelet aggregation and serum thromboxane B2 synthesis were significantly inhibited for all aspirin combinations tested at 14 days (p < 0.05). The 40/40 mg aspirin combination was less effective, because it reached its maximal effect very late at day 7 of the observation period compared with the other combinations.(ABSTRACT TRUNCATED AT 250 WORDS)