W. S. Lee

Starch Source Evaluation in Calf Starter: II. Ruminal Parameters, Rumen Development, Nutrient Digestibilities, and Nitrogen Utilization in Holstein Calves

Ruminal parameters, rumen development, nutrient digestibilities, and N utilization were estimated in Holstein calves fed starch from different sources. Ground corn, ground barley, ground wheat, and crimped oats were used to formulate 4 isostarch (25% of starter dry matter) pelleted diets. These diets were randomly allocated to calves (16 calves per treatment, 8 female and 8 male) and fed ad libitum along with mixed grass hay throughout the experiment. Ruminal contents and blood were sampled at d 35, 50, and 70 of age to estimate ruminal parameters and plasma beta-hydroxybutyrate, respectively. At d 70, twenty-four male calves (6/treatment) were randomly selected, euthanized, and forestomach weight, papillae length (PL), papillae width (PW), rumen wall thickness (RWT), and papillae concentration were measured. At d 63, twenty-four female calves (6/treatment) were randomly selected and moved to metabolism stalls to estimate total tract apparent nutrient digestibilities and N utilization. Female calves were given 2 wk for adaptation to experimental facilities and then total collections of feces and urine were made from d 77 to 84 of age. Ruminal pH at d 35 of age was higher in calves fed corn and oat diets than in those fed barley and wheat diets. Ruminal pH at d 50 and 70 of age was the lowest in calves on barley diets followed by those on oat and wheat diets and then by those on the corn diet. Ruminal total volatile fatty acid concentrations at d 35 of age were greatest in calves fed corn or wheat diets followed by those fed barley and oat diets. Calves on corn and wheat diets maintained greater ruminal volatile fatty acids concentrations at d 50 and 70 of age. Ruminal ammonia, acetate, propionate, butyrate, and blood beta-hydroxybutyrate concentrations were also greater in calves on the corn and wheat diets. Full and empty weights of forestomach, PL, PW, RWT, and papillae concentrations were greater in calves on corn and wheat diets. Daily average intake of nutrients (dry matter, crude protein, neutral detergent fiber, starch, Ca, and P) was greater in calves fed corn and wheat diets than in those fed barley and oat diets. Starch source did not influence the total tract apparent digestibilities of nutrients in calves. Daily N retention (g/d) was greatest on the corn diet followed by the wheat diet and then the barley and oat diets. In conclusion, calves on a corn diet have greater ruminal capacity to accommodate feed bulk. More physically and metabolically functional rumens in calves on corn and wheat diets probably resulted in greater feed consumption and N retention.

Influence of equalizing the gross composition of milk replacer to that of whole milk on the performance of Holstein calves

This study compared the performance of female Holstein calves fed either whole milk (WM) or milk replacer (MR) having similar gross composition to WM. Calves (n = 20) were separated from their mothers within 2 h of birth, weighed, moved into individual pens, and fed colostrum (10% of their BW over 2 feedings daily) for the first 3 d. Calves were alternately assigned to either WM (n = 10) or MR (n = 10) and were fed using mobile plastic bottles. At each feeding, diluted MR was prepared in buckets by mixing 0.143 kg of MR powder (as-is basis) in 1 L of lukewarm water. Calves on both treatments were fed (1.8 L/feeding) for 4 times daily for the first 25 d of age. Feeding frequency was reduced to 3 times daily for next 5 d, then to 2 times daily for next 14 d, and then to once daily during the last 5 d of the preweaning period. Feed intake, growth, and health variables were monitored until calves were 70 d of age. Mean daily consumption of WM and MR was similar in both treatment groups (P = 0.74). Initial BW of calves fed either WM or MR was similar (42.1 +/- 3.3 vs. 41.9 +/- 2.9 kg, respectively; P = 0.83). Calves fed WM or MR daily consumed similar amounts of calf starter (1,019 vs. 1,056 g, respectively; P = 0.32), hay (121.5 vs. 126.3 g, respectively; P = 0.30), and water (5.2 vs. 5.0 kg, respectively; P = 0.54). At weaning (d 49) and postweaning (d 70), BW was greater (P = 0.03 and P = 0.02, respectively) in calves fed WM than in those fed MR. Mean DMI from both solid and liquid feeds was not affected by the treatments during the preweaning (P = 0.21) and postweaning (P = 0.16) periods. Body weight gain efficiency during preweaning and overall was improved (P = 0.001 and P = 0.002, respectively) in calves fed WM than in those fed MR. Health (days scoured, rectal temperature, respiratory score, and general appearance score) and serum chemistry variables (glucose, total protein, urea N, nonesterified fatty acids, and creatinine) in calves were not affected (P >or= 0.12 and P >or= 0.12, respectively) by the treatments. Even though gross composition of the MR and WM was similar, growth was greater in calves fed WM. Calves fed WM consumed similar amounts of DM and were heavier than those fed MR, probably because of better bioavailability (digestion and assimilation) of nutrients and availability of some unknown growth factors from WM.

Hemato-biochemical and Cortisol Profile of Holstein Growing-calves Supplemented with Vitamin C during Summer Season.

Effect of vitamin C (VC) on biochemical, hematological and cortisol profile of growing Holstein calves during summer was investigated. Eighteen calves between 14 and 16 weeks of age were divided equally into two groups. One group received a diet supplemented with VC (20 g/d) for 60 days, while other non-supplemented diet fed group served as a control (CON). The temperature humidity index (THI) was recorded and computed during the experiment. From days 0 to 60, the THI exceeded 70. Blood samples were collected from the jugular vein of each calf at days 0, 15, 30, 45 and 60. Serum albumin and total protein decreased (p<0.05) in CON and VC calves with age. Serum glutamic-oxaloacetic transaminase concentrations were not affected by treatments. Serum creatinine, albumin and glutamic-pyruvic transaminase concentrations were higher in calves in the VC group than the CON group. While red blood cells, hemoglobin and hematocrit were lower (p<0.05) in VC calves, mean corpuscular volume, mean corpuscular hemoglobin, red blood cell distribution width and mean platelet volume were higher (p<0.05) in these VC supplemented calves. Leukocyte parameters including white blood cells and full term for lymphocytes were not affected by the treatments. Also, serum cortisol was not affected by treatments. At day 15, 30 and 45, the total VC in plasma was higher (p<0.05) in calves fed with VC. In conclusion, serum cortisols were not affected by plasma VC concentration, while some blood parameters were positively influenced in calves fed with VC.

Changes of immunophysiological characteristics in neonatal calves experimentally challenged with mixture of live bacteria and virus.

The aim of the present study was to define efficient immunophysiological parameters in neonatal Holstein calves with an experimentally induced microbial infection. Calves (n = 15) were challenged with classical swine fever virus (LOM strain) and Erysipelothrix insidiosa live vaccine by intravenous injection at 3 wk of age except for control calves (n = 4). The level of total serum IgA was significantly increased at 14 and 19 d post-experimental challenge (DPEC) compared with that in calves at -2 DPEC. At 5 DPEC, relative amounts of bacterial- and viral-specific IgA increased significantly and were sustained until 26 DPEC. In the hematology assay, the neutrophil:lymphocyte ratio (%) in whole blood was significantly decreased at 14 DPEC because of a significant increase in lymphocytes and a coincident decrease in neutrophils. The percentages of CD4+ and CD25+ T cells were significantly decreased at 14 DPEC and returned to initial levels at 19 DPEC. It is intriguing to note that the level of serum lactoferrin was significantly decreased by the microbial challenge within 1 d. The concentration of haptoglobin was increased within 3 d and gradually decreased in calves after microbial challenge. Our results suggest that 1) bovine serum lactoferrin plays an important role in the innate immune response against microbial infection at an early stage and 2) experimentally induced microbial challenge using porcine live bacterial and viral vaccine in calves could be a good experimental model to evaluate the effect of diet or stress induced by environmental change on the immune responses against microbial infection.

Changes in Salivary Cortisol Concentration in Horses during Different Types of Exercise

This study aimed to estimate the change of stress level in horses based on cortisol concentration levels in their saliva. A total of 61 horses were divided into the following three groups: i) tourist riding experience (TR, n = 23); ii) resting group (RR, n = 14); and iii) horse-riding education (ER, n = 24). The saliva samples of TR and ER groups were taken using plain cotton Salivettes four times a day: at 07:00 (basal), 11:00 (Exercise 1, after 1-hour exercise in the morning), 14:00 (Exercise 2, after 1-hour exercise in the afternoon), and 16:00 (Exercise 3, after 1-hour exercise in the afternoon). The saliva samples of RR were measured at the same time. The samples were analyzed using the SAS program general linear model procedure. In a percentage relative to the base value, cortisol levels in Exercise 3 were confirmed to decrease in all groups as compared to the basal value percentage in the following sequence: ER>TR>RR. The highest peak was confirmed in Exercise 2 (approximately 131%) of RR group and the lowest peak appeared in Exercise 3 (approximately 52%) of ER group. Therefore, resting without any particular exercise can also increase the stress level of horses. Thus, it is better to exercise, as exercise can reduce the stress level, even in cases when riders are clumsy or lack appropriate horse-riding experience. The results of the present study are useful to equestrian center owners and educational riding instructors in that they provide a meaningful insight into a better horse management.

The Effects of Therapeutic Horseback Riding on Equilibrium for Children with Disabilities

This study was performed on 26 disabled adolescent participants (16 male, 10 female) with the objective of testing changes in equilibrium after engagement in horseback riding. Participants of total 26 persons were divided into three groups as follows: 6 children with Cerebral Palsy (CP), 14 children with Intellectual Disability (ID) and 6 children with Autism (AT). Participants engaged in therapeutic horseback riding (TR) two times per week for 30 minutes per session. The 26 participants demonstrated a considerable increase in equilibrium ability, with an average increase in equilibrium time of sec after TR. Equilibrium also increased according to disability group: CP (P

Feed consumption, growth performance and carcass evaluation of Korean Holstein bulls fed either conventional or organic diets

Feed consumption, bodyweight gain and carcass evaluation of Holstein bulls fed either conventional (CON) or organic (ORG) diets were compared. Animals were randomly assigned to either CON (n = 15) or ORG (n = 15) treatments when 6 months old. Inclusion rates of the ingredients were similar in CON and ORG diets formulated for growing (6–12 months of age) and fattening (13–18 months of age) periods. Ingredients of organic origin were used to formulate ORG growing and fattening diets. The bulls on the CON diet were vaccinated, de-wormed and treated conventionally (with antibiotics) against any sign of illness. No dietary or implant growth promotant was used. The bulls on the ORG diet were vaccinated although they were not de-wormed or treated against illness using conventional methods. Instead they were allowed to recover naturally from illness for 3 days. However, if the illness persisted beyond 3 days, they were treated using conventional methods. Consumption of concentrate and rice straw during growing, fattening and overall periods (6–18 months of age) was the same in bulls fed the CON or ORG diets. Bodyweight gain, total dry matter (concentrate and straw) intake and feed to gain ratio during growing and fattening were not affected by the treatments. Daily feed cost and feed cost for unit gain were greater in bulls fed the ORG diet than those fed the CON diet. Weight of cold carcass and different carcass cuts of the bulls were not affected by the treatment. According to the Korean beef grading system, the carcasses from bulls fed either CON or ORG diets were graded similarly but were of lower quality. The Korean beef quality grade is primarily determined by marbling score. The bulls in this study were slaughtered earlier (at 18 months of age) than the conventional slaughtering age of beef cattle (~30 months) in Korea to produce highly marbled beef. It is concluded that the bulls fed ORG diets performed equally, and produced carcasses of similar quality, to those fed CON diets. However, feed costs for a unit bodyweight gain were significantly greater in the ORG diet compared with the CON diet.