Short Communication: effect of sodium butyrate, monensin, and butyric acid on the viability of Eimeria bovis sporozoites and their degree of damage to a bovine epithelial cell line.

This study aimed to determine the viability of sporozoites from Eimeria bovis when exposed to sodium butyrate (SB), monensin (MON), or butyric acid (BA), and to determine the effects of SB on sporozoite invasion of cells in comparison to MON as measured by the damage to a bovine epithelial cell line. To determine viability, isolated sporozoites were suspended in one of four treatments: control (CON) of cell culture medium alone, SB = 0.028 mg/mL suspended in control medium, MON = 0.01 mg/mL suspended in CON, and BA = 0.18 mg/mL suspended in CON. The number of live sporozoites was less for the MON and BA treatments compared to the CON and SB treatments. The number of dead sporozoites was similar regardless of treatment. There was a trend for treatment to affect the percent sporozoite viability. Control, SB and BA treatments were similar, while MON compared to control and SB had decreased percent viability. Results for MON, when compared to BA, were similar for percent viability. Lactate dehydrogenase (LDH) release was used to determine cellular damage to Madin Darby Bovine Kidney (MDBK) cells when exposed to E. bovis sporozoites in vitro. Cells were exposed to similar numbers of sporozoites and treated with: CON, SB = 0.028 mg/mL in control medium, MON = 0.01 mg/mL in control medium. Control LDH result (with sporozoites) was greater than both the SB and MON treatments while the LDH for SB and Mon and cells not exposed to sporozoites were similar. SB and MON were both shown to decrease cellular damage to MDBK cells as determined by decreased LDH release. SB has the potential to act as an anticoccidial alternative to MON.

Coccidial infections are a significant problem in food animals, including dairy cattle and although there are drug treatments available, these are banned in many countries. Potential alternatives to drugs like monensin include sodium butyrate (SB) and butyric acid (BA). These were evaluated to determine their effect on Eimeria bovis sporozoites in vitro. The number of viable sporozoites was similar between the control medium alone without monensin and SB treatments but reduced in monensin and BA treatments. The percent viable sporozoites were (percent viable is one measure) similar between the control and SB, and BA treatments while reduced in the monensin treatments. However, monensin and BA treatments were similar for percent viable sporozoites. SB and monensin similarly protected cells from damage caused by sporozoites. SB is likely to dissociate to sodium and butyrate as it passes through the digestive tract suggesting that sodium butyrate might be a viable anticoccidial for cattle.

The female to male calf sex ratio is associated with the number of services to achieve a calf and parity of lactating dairy cows.

Commercial dairy producers may get frustrated by the lower ratio of female to male calves born because female calves are more valuable than bull calves. Our objective was to determine if parity or stage of lactation at the time of breeding, using conventional semen, influenced the sex of the calf. Data from the University of Illinois and the University of New Hampshire dairy herds were collected and summarized for calf sex, the number of services to achieve a calf and the lactation number when conception of that calf occurred. Logistical regression procedures were used to analyze the dataset via version 9.4 of SAS. The final dataset contained 2,987 calvings, which consisted of 1,406 females and 1,581 males (47.1% and 52.9% for females and males, respectively). The frequency distribution of the number of services to achieve a calf was highest for the first service and progressively declined with increasing services (52.06%, 21.66%, 10.75%, 6.66%, 4.22%, and 4.65% for 1 to 6 services, respectively). The frequency distribution of calvings by lactation number was greatest for first lactation cows becoming pregnant with their second calf and declined with increasing parity (35.49%, 28.22%, 17.01%, 9.61%, 5.02%, 2.51%, 1.14%, 0.70%, and 0.30% for lactation numbers 1 to 9, respectively). Logistic stepwise regression indicated that the number of services to achieve a calf was significant in predicting the ratio of female to male calves. Calculation of odds ratios indicated that as the lactation number increased the likelihood of getting a bull calf decreased. Parity, services, and parity by services interaction were significant for cows having a greater number of parities and cows with a greater number of services yielding more heifer calves. However, an interaction occurred where cows with greater number of services along with greater parities more likely to have a bull calf. These data provide evidence that increasing the number of services to achieve a calf and increasing age of the cow increased the probability of a heifer calf being born. These data indicate that cows with greater parties (lesser cull rate) are more likely to produce heifer calves.

Effect of storage of wet brewer's grains with incremental levels of salt on apparent total tract nutrient digestibility and purine derivative excretion in dairy heifers.

Objectives of this study were to evaluate apparent total tract nutrient digestibility and purine derivative (PD) excretion in dairy heifers limit-fed diets containing wet brewer's grains (WBG) treated with salt. A 12-wk replicated 4 × 4 Latin square was conducted using 8 Holstein heifers of 224.5 ± 19.4 d of age, and body weight (BW) of 219.2 ± 28.1 kg (mean ± SD). Fresh WBG were treated with 0%, 0.8%, 1.6%, and 2.4% salt and stored for 4 d before being fed. Salt was added either to the WBG or separately to equalize the amount of salt in the diet. The diet contained 9% grass silage, 47% corn silage, 19% corn meal, 17.6% WBG and salt, 2% soybean meal, and 3% mineral mix. Diets were formulated to be limit-fed at 2.15% of BW, provide 14% crude protein (CP) and 2.27 Mcal metabolizable energy (ME)/kg of dry matter (DM). Heifers were adapted to diets for 14 d followed by a 7-d collection period. Dry matter intake (DMI) was recorded daily during the collection week while BW was recorded once a week. Urine and fecal samples were collected during the last 4 d of the collection period. Acid insoluble ash was used as an internal marker to determine apparent nutrient digestibility. Weight loss of WBG during storage was determined from days 1 to 11 and initial and final yeast and mold counts were determined. Final yeast counts were similar among treatments while final mold counts tended to be lesser (P = 0.07) for the 0.8% and 1.6% salt treatments. Urinary volume was similar among treatments while allantoin (P = 0.14), and uric acid (P < 0.01) and total PD excretion tended to increase (P = 0.13) quadratically. DMI was varied by treatment (linear, quadratic, and cubic effects P < 0.01). Heifers fed the 0.8% treatment had the least DMI. Nonfiber carbohydrate (NFC) digestibility linearly decreased (P < 0.04) as salt increased. Digestibilities of DM, and organic matter (OM), tended to decrease (P < 0.10) with increasing levels of salt added to WBG. Fat digestibility was quadratic with the greatest value for the 1.6% treatment. Treating WBG with salt reduced its deterioration based on lesser mold counts for the 0.8% and 1.6% treatments. These treatments had resulted in greater fat digestibility and tended to have increased PD excretion suggesting improved microbial protein synthesis.

Growth performance and apparent total tract nutrient digestibility of limit-fed diets containing wet brewer's grains to Holstein heifers.

The objective of this study was to evaluate the growth performance and apparent total tract nutrient digestibility of Holstein heifers limit-fed diets containing different amounts of wet brewer's grains (WBG). A 12-wk randomized complete block study was conducted using 30 yearling Holstein heifers [378 ± 27 d of age, and body weight (BW) of 357.8 ± 27.6 kg (mean ± SD)]. Treatments were 0%, 10% and 20% of WBG on a dry matter (DM) basis and diets were formulated to be limit-fed for dry matter intake (DMI) at 2.35% of BW and provided 15% crude protein (CP) and 2.27 Mcal metabolizable energy/kg of DM. Dry matter intake was recorded daily, while BW and skeletal measurements were measured every 2 wk. During week 12, fecal samples were collected directly from the rectum over four consecutive days and composited by heifer to determine apparent total tract nutrient digestibility using acid detergent insoluble ash as a marker. Data were analyzed using the MIXED procedure of SAS. Dry matter intakes, BW, and average daily gain were not different among treatments (P = 0.2, P = 0.4, and P = 0.6, respectively). Dry matter intakes ranged from 8.6 to 9.0 kg/d. Average BW were 404.4, 411.5, and 409.3 kg for heifers fed the 0%, 10%, and 20% WBG diets, respectively. Average daily gains were 1.03, 1.04, and 0.96 kg/d for heifers fed the 0%, 10%, and 20% WBG diets respectively. Skeletal measurements and body condition scores (BCS) were not different among treatments except for the change in heart girth (P < 0.01) and initial BCS (P < 0.01). Apparent total tract digestibilities of DM, organic matter, CP, fat, and hemicellulose were greater or tended to be greater in heifers fed 0% and 20% WBG treatments than heifers fed 10 % WBG (P = 0.04, P = 0.04, P = 0.06, P = 0.06, and P = 0.01, respectively). Neutral detergent fiber, acid detergent fiber, and fat digestibilities were similar among treatments (P = 0.2, P = 0.3, and P = 0.3, respectively). During the digestibility phase, DMI tended to be greater (P = 0.08) for the 10% WBG treatment. These results demonstrate that limit-feeding heifers with diets containing up to 20% WBG could replace soybean- and corn-based concentrates in diets without adverse consequences to the heifer growth performance.

Effect of cinnamaldehyde on feed intake, rumen fermentation, and nutrient digestibility, in lactating dairy cows1.

The objective of this study was to evaluate the effect of cinnamaldehyde, on feed intake, rumen fermentation, nutrient digestibility, milk yield, and components in lactating dairy cows. Six lactating Holstein dairy cows (3 ruminally cannulated and 3 noncannulated) averaging 263 ± 41 d in milk (DIM) and 754 ± 45 kg of BW at the beginning of the study were used. Cows were randomly assigned to 1 of 3 treatments in a replicated 3 × 3 Latin square design with 19 d periods (14 d for diet adaptation and 5 d for sample collection). Treatments were 0, 2, or 4 mg/kg of BW of cinnamaldehyde. Cinnamaldehyde was mixed with 40 g of corn meal and top-dressed onto the total mixed ration (TMR). Diet was fed as a TMR and contained 37% corn silage, 18.5% mixed-mostly grass silage, 24.5% energy supplement, 16.5% protein supplement, and 3.5% vitamin and mineral mix on a DM basis. The dietary nutrient composition averaged 15.1% CP, 37.8% NDF, and 24.7% ADF. Cows were fed and milked twice daily. No differences were observed for DMI (mean = 24.6 kg/d), milk yield (mean = 28.4 kg/d), 3.5% fat-corrected milk (FCM; mean = 30.6 kg/d), and 3.5% energy-corrected milk (ECM; mean = 30.7 kg/d). The dose of cinnamaldehyde did not have any effect on milk components, rumen fermentation, or pH. There were no differences in nutrient digestibility, but there was a trend for a quadratic effect for DM digestibility (P = 0.09): 74.4%, 76.3%, and 73.7% for treatments 0, 2, and 4 mg/kg of BW of cinnamaldehyde, respectively. A linear effect (P = 0.02) and a quadratic effect (P < 0.02) observed for urinary urea N and a quadratic effect (P = 0.03) for allantoin and total purine derivatives with the 2 mg/kg treatment being the lesser value. These data suggest that cinnamaldehyde at these dosages may have an antimicrobial effect in the rumen as suggested by a lesser concentration of urinary total purine derivatives. Overall, supplementing lactating dairy cows with cinnamaldehyde had no effect on feed intake, milk yield, or milk components. However, it appears that cinnamaldehyde has a negative effect on rumen microbial protein synthesis as suggested by the reduced concentration of urinary purine derivatives.