Jejunal mucosal lactase activity from birth to 3 weeks in conventionally raised calves

The descending portion of the duodenum of 6 Holstein calves less than 24 hours old was cannulated. Sequential biopsy specimens of the proximal jejunal mucosa were obtained every other day for 3 weeks. Lactase activity in the mucosal specimens was determined and was highest at day 1, but decreased with age. Mean lactase activity was significantly (P less than 0.05) higher for days 1, 3, 5, and 7, compared with days 19 and 21.     

Intraruminal administration of milk in the calf as a model for ruminal drinking: Morphological and enzymatical changes in the jejunal mucosa

In order to develop a calf model for studying the syndrome of ruminal drinking (RD) in veal calves, three dual-fistulated calves were used to test the effect of intraruminal administration of milk replacer on the jejunal mucosa. Biopsies of the proximal jejunal mucosa were taken through a jejunal fistula and the mucosal morphology and the activities of two brush border enzymes, lactase and alkaline phosphatase, were determined.Means of villus length and brush border enzyme activities decreased during the period of intraruminal administration of milk. The hyperplastic villus atrophy in this model was similar to that found in chronic RD patients in previous studies. This could not be associated with isolation of pathogenic micro-organisms from the faeces and is probably the consequence of the intraruminal milk feeding procedure itself.Clinical recovery from the signs of RD occurred rapidly after intraruminal administration of milk ceased and was followed by restoration of villus length and brush border enzyme activities 3–4 weeks later.     

Effect of orally administered epidermal growth factor on the jejunal mucosa of weaned pigs

The effect of ingested epidermal growth factor (EGF) on the small intestinal mucosa of conventionally weaned pigs was determined. At 21 days of age, 39 pigs were randomly distributed into suckling and weaned treatment groups that were administered 124 micrograms of EGF, 372 micrograms of EGF, or the dosing compound daily. Fecal water content was determined daily. On postweaning days 0, 3, 6, and 9, representative pigs from each group were euthanatized, and jejunal mucosa samples were collected for determination of villus-to-crypt ratio, total protein content, disaccharidase activities, and microbiological populations. At postweaning day 3, the 372-micrograms dose of EGF significantly (P less than or equal to 0.05) increased jejunal lactase and sucrase activities in the weaned pigs. Increased lactase activity was not greater than that of the suckling pig controls, whereas sucrase activity was significantly (P less than or equal to 0.05) higher than that of the suckling pig controls. Significant changes were not observed in villus-to-crypt ratio, mucosal protein content, or disaccharidase activities on other collection days.     

Oral fluid therapy in neonatal ruminants and swine

Definitive recommendations regarding the best method to treat the diarrheic calf cannot be made at this time. The exact recommendation will probably depend on the situation. At the present time, I do not believe it is detrimental to withdraw milk from the diet for periods up to 24 to 36 hours, as long as the calf is in good condition and is returned to a full ration (maintenance plus) of milk within 3 to 5 days from the start of milk withdrawal. Milk withdrawal is most likely to be beneficial in those situations in which the calf is depressed and has lost its sucking reflex. Oral electrolyte solutions should be fed at the rate of 4-6 L/day if diarrhea is profuse or if the calf is depressed. As the calf feels better and the severity of diarrhea decreases, the amount of oral electrolyte solution can be reduced. It is sensible to continue feeding oral electrolyte solution, perhaps at the rate of 2 L/day, as long as the calf scours. Products containing 40-80 mEq/L of alkalizing agent give the best results. The higher concentrations may be more effective in older calves. Products containing bicarbonate or metabolizable base can be used when the calf is held off milk, whereas only solutions that contain a metabolizable base should be used if the calf is fed milk that day. Milk withdrawal may only be beneficial in calves that are losing their interest in sucking. Early reintroduction to milk and avoidance of milk deprivation in bright calves will help maintain condition and may boost immune function and mucosal repair. Calves that are held off milk for more than 2 days and calves that are deprived of milk while in poor condition should be fed a high-energy electrolyte solution. Beef calves tend to be treated while they are still on the dam, and if they are separated from the cow, it is usually only for a short period. This maintains the cow's lactation and maternal instincts. Cow's milk is better digested than many milk replacers and is available at a steady rate because calves suck frequently. Calves maintained on cow's milk should be fed an oral electrolyte solution containing a metabolizable base. Gastric fill from the electrolyte solution will tend to reduce milk consumption. It is important to prevent the calf from gorging on milk, which sometimes happens when a calf that is depressed and not sucking regains its appetite and has access to a very full udder. Cows that have been separated from their calf or that have distended udders should be milked out.     

Correction of metabolic acidosis in diarrheal calves by oral administration of electrolyte solutions with or without bicarbonate

Acid-base balance was evaluated in calves with experimentally induced viral diarrhea. When blood pH decreased to less than 7.200, calves were assigned to treatment groups and fed milk replacer, electrolyte solution without bicarbonate, or electrolyte solution containing bicarbonate. Calves in the electrolyte treatment groups had lower mortality (P less than 0.05), were better hydrated (P less than 0.05), and were less acidotic (P less than 0.05) than calves fed milk replacer. Bicarbonate-containing electrolyte solution restored acid-base balance (P less than 0.05) and corrected depression better (P less than 0.05) than electrolyte solution that did not contain bicarbonate. Both electrolyte solutions were equally good at correcting dehydration.     

Effect on young calves of a one-hour feeding stop during a 19-hour road journey.

This study examined the effects of transporting calves less than four weeks of age on a journey at the limit of the maximum time laid down by recent EU legislation. In both summer and winter, 45 calves were transported by road for 19 hours. The journey included a one-hour break on the lorry in which the calves were given either a glucose/electrolyte solution, water, or nothing at all. Control groups of 15 calves remained on farm and were fed normally. The effects of the journey were greater during winter when liveweight loss was greater and more prolonged, and the calves suffered a depression in body temperature. Mid-journey feeding was of minimal benefit. Feeding electrolytes reduced the extent of dehydration as measured by changes in plasma total protein and albumin concentrations, but there was some indication that giving water alone was detrimental. Most of the variables which changed during the journey had recovered in line with the values in the control animals within 24 hours of the end of the journey, but the calves' liveweight and plasma creatine kinase activity took up to seven days to stabilise. The study highlighted the problem that young calves have in maintaining body temperature during transport, especially during colder weather.     

The effects of feeding milk to diarrheic calves supplemented with oral electrolytes.

The effects of feeding different levels of milk to diarrheic calves (n = 19) supplemented with oral electrolytes were investigated. In the early stages of the disease the calves were fed either enough milk to maintain normal growth in a healthy calf, one half that volume or no milk. The three groups were further subdivided according to whether or not the electrolyte solution contained bicarbonate. A full milk ration allowed uninterrupted weight gains of 1% body weight/day (p = 0.003), but caused greater inappetence (p = 0.003 to 0.037) at the beginning of the trial than lower levels of milk intake. Electrolyte solutions with bicarbonate reduced growth rates in milk fed calves (p = 0.014). The density of fat stores increased with the level of milk feeding (p = 0.04 to 0.053). The mitotic index of the duodenal mucosa increased with milk feeding (p = 0.08), indicating a superior mucosal regeneration potential. Thymic atrophy was pronounced in those calves fed no milk (p = 0.001). It was concluded that the continued feeding of milk to diarrheic calves was beneficial. Electrolyte solutions containing bicarbonate should be avoided when milk is fed to diarrheic calves.     

Hypernatremia in Calves

Hypernatremia (sodium chloride intoxication) is described in two calves due to presumed mixing errors of oral electrolyte solutions while undergoing therapy for neonatal diarrhea. The experimental induction of hypernatremia in two clinically normal calves is also reported. Physical findings in diarrheic calves included depression, weakness, dehydration, and diarrhea. Serum sodium concentrations were found to be 171.6 mEq/l and 208.0 mEq/l, respectively. Treatment with intravenous fluids was attempted in both cases, but one calf died after 6 hours and the other calf died after 2 days and exhibited periodic convulsions before death. Experimental induction with oral administration of 1 l of electrolyte concentrate, which contained approximately 2750 mEq sodium revealed that the normal calves would willingly consume the solution as mixed with milk and develop clinical signs of hypernatremia within 6 hours of administration. Serum sodium concentrations of 176.0 and 179.8 were found in the experimental calves and coincided with the onset of overt depression and weakness, at which time they were euthanatized. Cerebrospinal fluid electrolyte analysis paralleled the serum electrolyte alterations.     

Changes in small intestinal morphology and flora associated with decreased energy digestibility in calves with naturally occurring diarrhea

Fecal composition was studied in 5 healthy Holstein calves and in 10 with naturally occurring diarrhea. The calves were between 5 and 21 days of age. The mean fecal contents of fat, lactate, and acetate were higher in the calves with diarrhea than in the healthy calves (P less than 0.01). On the basis of calculated values, the mean caloric uptake from milk was decreased by 31% in diarrheal calves, compared with that in controls. At least half of the diarrheal calves were calculated to be in negative energy balance during the fecal collection period. This occurred in spite of consumption of a diet sufficient to provide more than enough energy for maintenance in healthy calves. The mean values for villous lengths were decreased at all portions of the small intestine in the calves with diarrhea, compared with those values in healthy calves. Similarly, the mean intestinal epithelial lactase activities were decreased in the calves with diarrhea, compared with those activities in healthy calves. Villous length was negatively correlated with fecal lactate content (r = -0.88 in the duodenum, r = -0.66 in the jejunum, and r = -0.80 in the ileum), but not with fecal fat content. Intestinal lactase activity in the cranial portion of the intestine tended to be negatively correlated with fecal lactate content. The mean concentration of total viable bacteria in the ileum was 1,000-fold higher in the diarrheal calves than in the healthy calves (10(9) vs 10(6)/5-cm intestinal segment.(ABSTRACT TRUNCATED AT 250 WORDS)     

Intestinal changes associated with rotavirus and enterotoxigenic Escherichia coli infection in calves

Newborn calves inoculated with rotavirus, enterotoxigenic Escherichia coli (ETEC) serotype 020:K' x 106':K99:HNM, either alone or in combination, became depressed, anorectic, diarrhoeic and dehydrated. ETEC did not adhere to the intestine although there was extensive proliferation in the lumen. Only slight mucosal changes were induced by ETEC and the activity of membrane bound lactase remained normal. More severe mucosal damage and a decrease in lactase activity were found in newborn calves inoculated with either rotavirus or rotavirus and ETEC in combination. The most severe clinical illness was found in calves inoculated with both rotavirus and ETEC. Calves inoculated at 1 week of age with either rotavirus or ETEC remained clinically normal. Rotavirus infection produced slight mucosal changes and a reduction of lactase activity. In contrast, colostrum-fed or suckling calves up to 2 weeks old inoculated with both rotavirus and ETEC became clinically affected, showed severe mucosal damage and decreased lactase activity. There was no bacterial adhesion to the intestinal mucosa as observed by immunofluorescent labelling and light microscopy.     

Modification of the concentration of creatinine and sodium in blood serum and urine and the fractional elimination of sodium by electrolyte therapy in calves]

In 32 calves, creatinine and sodium concentrations were determined in blood and urine samples taken simultaneously four times during two periods of two days each (control period: milk or milk replacer; trial period: oral electrolyte solution). Creatinine urine/serum ratios and fractional elimination of sodium (FENa) were calculated. The influence of the type of liquid feed on these parameters was evaluated statistically. Calves fed milk replacer had higher urine sodium concentrations and FENa than calves fed whole milk. All parameters determined were influenced by intake of oral electrolyte solution: creatinine concentrations in serum and urine decreased, whereas sodium concentrations in serum and urine, as well as FENa, increased. It is concluded that sodium content of liquid feed significantly influences FENa.     

Treatment of Neonatal Calf Diarrhea with an Oral Electrolyte Solution Supplemented with Psyllium Mucilloid

Dairy calves under 14 days of age with naturally occurring, uncomplicated diarrhea were treated for 3 days with a hypertonic oral electrolyte solution with (n = 15) or without (n = 12) psyllium. Clinical response and clinical pathology data were compared between the 2 groups. Glucose absorption was evaluated on days 1 and 3 by measurement of plasma glucose and lactate and serum insulin concentrations for 4 hours after formula administration. On day 1, glucose, lactate, and insulin concentrations were lower in psyllium-fed calves than in control calves, with significant differences noted in glucose and lactate concentrations at several time points ( P < 0.05). Plasma lactate concentrations were higher at several times in both treatment groups on day 3 than on day 1 ( P < 0.05). Fecal consistency was markedly different in psyllium-fed calves as compared with control calves within 24 hours of psyllium supplementation. Fecal percent dry matter content was lower in psyllium-fed calves than in control calves at least once a day during supplementation and on day 3 compared with day 0 in the psyllium-fed calves ( P < 0.05). There were no significant differences in clinical performance scores, hydration status, arterial blood gas, serum anion gap, electrolyte, or total CO, concentrations. Addition of psyllium to an oral electrolyte solution resulted in immediate alterations in glucose absorption without impairing rehydration in diarrheic calves, but differences were transient and did not affect clinical outcome.     

Effects of food withdrawal and transport on 5- to 10-day-old calves

The effects of food withdrawal for 30 hours and transport for up to 12 hours on 5- to 10-day-old calves were determined by monitoring plasma concentrations of glucose, beta-hydroxybutyrate, urea, lactate and creatine phosphokinase. In addition gamma-glutamyl transferase activity, packed cell volume, total plasma protein concentration, bodyweight and rectal temperature were recorded. Food withdrawal for 30 hours caused hypoglycemia but calves maintained normothermia and although their beta-hydroxybutyrate level increased indicating lipid mobilisation, the changes in blood urea level were minimal indicating low amino acid catabolism. When calves were transported for 12 hours in addition to having food withdrawn for 30 hours, they remained normoglycemic for six hours longer than non-transported calves, probably due to an effect of muscular activity during bracing against truck movements. Stocking calves at a lower density during transport apparently had a beneficial effect, as calves were able to lie down throughout the journey and therefore produced a similar metabolic profile to resting, non-transported animals. Transport and food withdrawal had no obvious effects on calf hydration. The results of this study suggest that food withdrawal for up to 30 hours and transport for up to 12 hours had no detrimental effects on the metabolism of healthy and clinically normal calves. With correct feeding regimes and transport protocols, welfare compromise in young, healthy calves being transported for up to 12 hours can be minimised when they are slaughtered within 30 hours of the start of transport.     

Effects of electrolyte solutions for oral administration on clotting of milk.

The effect of electrolyte solutions commercially formulated for oral administration on clotting of milk was investigated in vitro. Rennet or abomasal fluid was used as the clotting agent. Electrolyte solutions that contained large amounts of bicarbonate or citrate (greater than 40 mEq/L) had marked adverse effects on milk clotting, probably because bicarbonate increased pH and because citrate chelated calcium. Addition of solutions that did not contain alkalinizing agents resulted in normal or enhanced clotting, and enhancement was associated with the presence of acid phosphate salts. Electrolyte solutions that included acetate as the alkalinizing agent did not interfere with milk clotting as long as pH of the final solution was acidic and minimal amounts of citric acid salts were present (less than 10 mEq/L). Acetate-containing electrolyte solutions can be used for oral administration in calves in which alkalinization of blood without interference with milk clotting is desired.     

Tissue disposition and depletion of penicillin G after oral administration with milk in unweaned dairy calves

OBJECTIVE: To determine tissue depletion of penicillin G in calves after oral ingestion with milk replacer and estimate a withdrawal period. DESIGN: Longitudinal controlled trial. ANIMALS: 26 Holstein calves. PROCEDURE: Once daily, 24 calves were fed milk replacer containing procaine penicillin G (0.68 mg/kg [0.31 mg/lb] of body weight); 2 calves served as controls. After 1 feeding, 12 calves were euthanatized in groups of 3 each 4, 6.5, 9.5, and 13 hours after feeding. After 14 days, 12 calves were euthanatized in groups of 3 each 4, 6.5, 9.5, and 13 hours after the final feeding. Concentrations of penicillin G were determined in tissues, blood, and urine by use of high-performance liquid chromatography. RESULTS: Penicillin G was not detected in muscle samples of treated calves. The highest concentrations of penicillin G in plasma, kidney, and liver were 13 ng/ml, 92 ng/g, and 142 ng/g, respectively. Thirteen carcasses had violative drug residues; 12 had violative residues in the liver only, and 1 had violative residues in the liver and kidney. A 21-hour withdrawal period was estimated. CONCLUSIONS AND CLINICAL RELEVANCE: Liver had the highest concentration of penicillin G and was most likely to have violative residues. Feeding calves milk containing penicillin G has the potential to cause violative drug residues in tissues. It is recommended to observe an appropriate withdrawal time prior to slaughter if calves are fed milk from cows treated with penicillin G.     

Comparison of two oral electrolyte solutions for the treatment of dehydrated calves with experimentally-induced diarrhoea

We compared the ability of two oral electrolyte solutions to resuscitate calves with experimentally induced diarrhoea and dehydration. Sucrose solution, furosemide, spironolactone, and hydrochlorothiazide were administered to 18 male Holstein-Friesian calves to induce diarrhoea and dehydration. Clinical changes after 24 h included severe diarrhoea, moderate dehydration (8-10% body weight), azotemia, and clinical depression. Calves were then randomly assigned to one of three treatment groups (milk replacer, 2 L every 12 h; hyperosmotic oral electrolyte solution, 2 L every 12 h; iso-osmotic oral electrolyte solution, 1.5 L every 6 to 12 h) and followed for an additional 48 h.Compared to feeding milk replacer, the hyperosmotic solution significantly (P< 0.05) improved hydration status, increased body weight, maintained urine production, decreased the degree of clinical depression and prevented development of metabolic acidosis, although serum glucose concentration was decreased at 24 h and 48 h. The hyperosmotic solution produced a similar resuscitative response to the iso-osmotic solution, but maintained higher serum glucose concentrations and lower serum beta-OH butyrate and non-esterified fatty-acid concentrations, indicating that the hyperosmotic solution provided greater nutritional support. The hyperosmotic solution rehydrated calves faster and more effectively than feeding equivalent volumes of milk replacer and can, therefore, be recommended as part of the initial treatment of dehydrated calves with diarrhoea.     

Glucose and galactose absorption after ingestion of milk containing hydrolysed lactose in calves with diarrhoea

Ten calves which had contracted acute diarrhoea caused by rotavirus, coronavirus and Cryptosporidium were used to test the hypothesis that feeding lactose-hydrolysed cow's milk instead of unprocessed cow's milk improves sugar absorption in diarrhoeic calves. The animals were rehydrated with an orally administered solution containing electrolytes and glucose. Thereafter the calves received one test meal of whole fresh cow's milk whose lactose had been hydrolysed by added lactase and one test meal of unprocessed cow's milk at an interval of 24 h in a cross-over design trial. In comparison with unprocessed milk, the intake of milk containing hydrolysed lactose resulted in a slight decrease of mean breath hydrogen concentration (P = 0.18), but also a slight decrease of mean blood galactose concentration (P = 0.14). There was no treatment effect on mean plasma glucose concentration. Peak plasma glucose and blood galactose concentration tended to be delayed after the intake of lactose-hydrolysed milk, which implies that gastric emptying was probably delayed. The results show that feeding milk which contains hydrolysed lactose does not significantly improve lactose utilization in calves that are suffering from benign infectious diarrhoea.     

Hemato-biochemical changes, disease incidence and live weight gain in individual versus group reared calves fed on different levels of milk and skim milk

A 2 × 3 factorial design was used to study the impact of rearing systems, individual (I) versus group (G) and different levels of milk/skim milk feeding (F1, F2 and F3) on hemato‐biochemical profile, disease incidence and average daily gain of crossbred (Bos indicus × Bos taurus) calves. Six calves were taken in each group on the basis of their birth weight and housed in individual (2.20 × 1.16 m²/calf) or in group pens (2.20 × 1.03 m²/calf). After 3 days of colostrum feeding, calves were allocated to one of three different milk feeding schedules: milk fed up to 8 weeks of age (F1), milk up to 4 weeks followed by 50% replacement by skim milk up to 6 weeks and 100% thereafter (F2) and 100% replacement of milk with skim milk after 4 weeks (F3). Calf starter and cereal green fodders were fed ad libitum from the second week of age and continued for 14 weeks. Parameters on health and disease profiles of calves (disease incidence, duration of illness, response to treatment and recovery) and weekly live weight change were recorded. Calf scour predominated (52.8%), followed by joint ill (25.0%) and respiratory infections (19.4%). The disease incidence was greater (P < 0.01) in individually housed calves (94.4 vs. 55.9%). The management of navel ill required longer recovery (7.01 days) followed by joint ill (4.87 days) and respiratory infection (4.86 days). The average daily gain during 0–14 weeks of age was higher (P < 0.01) in group‐housed calves (433 ± 22 vs. 355 ± 31 g), while the effect of feeding was not significant. Blood samples collected at 4, 8 and 14 weeks of age showed some periodic higher concentrations (but within normal range) of plasma urea and total protein in group housed calves on F2 and F3 feeding schedules in response to high protein intake. Other parameters remained non‐significantly different. Thus, group‐housed calves can be reared successfully with comparatively better performance and less illness than individually housed ones under the present health care and housing management system. However, the system should not be used as a substitute for good management, and frequent observations of calves should be an integral part of any successful rearing program.     

Developmental alterations in the regulation of glucagon and insulin secretion in Holstein calves

Twenty-one Holstein bull calves were randomly assigned at birth to 3 groups. Two groups (each of 7 calves) were raised as follows: fed a milk diet alone or fed milk with grain supplementation after 2 weeks of age; studies were done when calves reached 4 weeks of age. The 3rd group was fed on milk with grain supplementation until weaning after which the calves were maintained on grain and pasture. These calves (older calves) were studied at 12 weeks of age. Either propionate (0.28 mmol/kg) or glucose (0.56 mmol/kg) was injected IV in a random order. Samples of blood were obtained from the calves before and immediately after injections were done and at 2, 5, 10, 15, 30, 45, and 60 minutes after secretagogue injection. Plasma was examined for glucose by a glucose oxidase procedure and for immunoreactive insulin (IRI) and glucagon (IRG) by radioimmunoassay. The IRI response to the injection of glucose was greater in older calves (P less than 0.02). Patterns of IRI secretion, as determined by heterogeneity of regression, showed age differences for both secretagogues (P less than 0.05). Base-line IRG was greater in milk/grain-fed calves than in milk-fed calves (P less than 0.05). Mean IRG response to propionate injection was higher (P less than 0.05) in milk/grain-fed calves than in milk-fed calves. Plasma glucose concentration increased in older calves, but decreased in milk-fed calves after propionate injection. The data indicate that maturation in the ruminant is accompanied by altered regulation of insulin and glucagon secretion.(ABSTRACT TRUNCATED AT 250 WORDS)     

Resistance of neonatal calves given colostrum diet to oral challenge with a septicemia-producing Escherichia coli.

Twenty Holstein-Friesian male calves were obtained within 4 hours after bith (colostrum deprived) and allotted to 1 of 4 groups, each given a different feeding: colostrum, milk replacer, polyvinylpyrrolidone (PVP), and saline solution (0.85% NaCl). Each calf was fed 2 L of the respective diets every 12 hours. Rectal temperatures were recorded and blood samples were collected immediately before each feeding. At approximately 27 hours of age, all calves were inoculated orally with 1.5 X 10(10) viable organisms of a septicemia-producing Escherichia coli serotype O26: K60:NM. Within 8 hours, all calves had diarrhea. Coli-septicemia (E coli cultured from liver, spleen, and cardiac blood) was present in 1 of the 5 calves fed colostrum, in 5 or the 5 calves fed milk replacer, in 5 of the 5 calves fed PVP, and in 4 of the 5 calves fed saline solution. At necropsy of the calves (12 to 48 hours after oral inoculation), the same organism was isolated by cultural technique from small intestines of 19 of the 20 calves. Serum immunoglobulin G concentrations increased (P less than 0.01) in calves fed the colostrum diet in sharp contrast to the agammaglobulinemia occurring in calves fed the milk replacer, PVP, or saline solution. Results indicate that colostrum fed to the calf soon after birth provides protection from colisepticemia, but does not prevent the diarrhea of colibacillosis.