A field survey on the status of internal parasites in calves on organic dairy farms in southwestern Sweden

Prevalence and risk factors associated with donkey gastrointestinal parasites in Shashemane and Suburbs, Oromia Region, Ethiopia

Background

Gastrointestinal parasites are the cause of morbidity and mortality in working donkeys and reduce their working performance.

Methods

A cross-sectional study was conducted from November 2020 to July 2021 to assess gastrointestinal parasite infection in working donkeys in Shashemane and the surrounding district. A total of 395 donkeys were randomly sampled for the study, and an examination was conducted using faecal egg count and the Baermann technique.

Results

Out of the 395 sampled donkeys, different types of gastrointestinal parasites were identified. The parasites identified during the study were Strongyle spp. (100%), Oxyuris equi (10.1%), Parascaris equorum (23.8%), Fasciola spp. (0.3%), Gastrodiscus aegyptiacus (4.6%), Strongyloides westeri (47.8%) and Anoplocephala perfoliata (0.5%). Identification of L₃ larvae of GI parasites revealed that Cyathostomes spp. (96.2%), Strongylus vulgaris (92.9%), Trichostrongylus axei (90.4%), Strongylus edentatus (89.4%), and Dictyocaulus arnifieldi (49.6%) were the most prevalent. Infection with one species of helminth was more common (60.8%).

Conclusions

Thus, working donkeys in the present study area were infected with Strongyle spp. (100%), Strongyloides westeri (47.8%), Parascaris equorum (23.8%), Oxyuris equi (10.1%), Gastrodiscus aegyptiacus (4.6%), Anoplocephala perfoliata (0.5%) and Fasciola spp. (0.3%) parasites. Hence, comprehensive donkey health, management, and implementation of appropriate parasite control strategies should be implemented to alleviate these problems.

A Comparison of the Prevalence of the Parasites of the Digestive Tract in Goats from Organic and Conventional Farms

The aim of the study was to compare the prevalence and intensity of gastrointestinal parasitic infections in goats kept on organic (n = 76) and conventional farms (n = 82). In general, a higher prevalence of some gastrointestinal parasitic infections was found in the conventional farms compared to the organic farms: the mean prevalence of Eimeria spp. was 85.4% in conventional farms and 77.6% in organic farms, that of Fasciola hepatica was 6.10% in conventional farms and 2.63% in organic farms, and that of Moniezia expansa was 31.7% and 17.1%, in conventional and organic farms, respectively. Both farm types demonstrated a similar mean prevalence of nematodes (80.3 vs. 84.2%). Conventional farms demonstrated a significantly higher intensity of infection with E. arloingi, Haemonchus spp., Nematodirus spp. and Moniezia expansa compared to organic farms. They also demonstrated a higher intensity of infection with Eimeria spp. than organic farms. The prophylactic programs used to combat parasitic infections in both types of farms appear ineffective and require improvement. There is a need for goat herds to be covered by ongoing parasitological monitoring. It is also recommended that keepers employ rotational or intensive rotational grazing methods and take care to ensure the hygiene of animal quarters and livestock rooms.

Changes in biochemical analytes in calves infected by nematode parasites in field conditions

Parasitic infections caused by nematodes are a major problem in bovines that resulting in losses in animal health and production. Thus, the aim of this study was to evaluate alterations in selected serum biochemical analytes in calves naturally infected with gastrointestinal (GI) and pulmonary nematodes without clinical signs. For this, samples of feces and blood of 86 calves were collected. Fecal egg counts (FEC) were determined using the modified McMaster technique with a sensitivity of 50 eggs per gram of feces (EPG). Positive nematode FEC was processed for coproculture using pooled samples to identify Strongylidae infective larvae (L3). First stage-larvae (L1) of Dictyocaulus viviparous were identified by a modified Baermann method. The biochemical analytes determined were: acute phase proteins such as haptoglobin and paraoxonase type 1; the enzymes acetylcholinesterase; butyrylcholinesterase; the lipid profile (triglycerides and total, HDL, and LDL-cholesterol); serum iron profile (iron and unsaturated iron-binding capacity); total protein and albumin; pancreatic profile (amylase and lipase); and minerals (phosphorus and calcium). The calves were divided into four groups according to the results of EPG and the modified Baermann method. Group 1: healthy control animals (n=16); Group 2: calves with only GI parasites (n=51): This group was sub-divided into sub-groups according to the EPG threshold: 2a-GI parasites with low EPG (n=23), and 2b-GI parasites with high EPG (n=28). Group 3: animals with only lungworms (n=5), and Group 4: calves with lung+GI parasites (n=14). The more prevalent genera in all coprocultures were: Cooperia spp., Haemonchus spp., Oesophagostomum spp., and Trichostrongylus spp. The nonparametric Kruskal-Wallis test was used to compare the groups and Dunn's post-test was used for multiple comparisons as the data was not normally distributed (P<0.05). The haptoglobin concentration increased in calves with GI and pulmonary parasites. A significant increase in acetylcholinesterase was observed in calves infected with lungworms. Cholesterol, triglycerides, HDL, and LDL concentrations decreased but lipase concentration increased in calves with GI parasites. Therefore, this paper provides an overview of the biochemical effects produced by nematode parasites in calves in field conditions. These findings in calves without any evident clinical signs of disease could provide an indication of GI parasites and lungworm infection, especially in an endemic area for these parasites.

Calving season is a stronger determinant of worm burdens in pasture-based beef production than the level of residual larval contamination at turnout

The combined influence of (1) calving period (early or late) and (2) overwintering contamination by residual infective larvae (high or low) on subsequent exposure of suckler calves to gastrointestinal nematodes was investigated. We found that the effect of calving date was greater than the level of residual contamination. This was because the adult cows produced large quantities of manure containing small amounts of nematode eggs from turnout, which significantly contaminated the pasture, and thereby, reduced the effect of prior high-low contamination. Early born calves were found to be more heavily exposed to parasites, most likely due to ingesting more herbage than those born later. Late-born calves also had relatively high antibody levels at turnout, which first decreased and then increased again. We suggest that the high antibody levels at turnout reflect passive transfer of maternal antibodies through the milk. There was also a significant difference in animal performance, with the more heavily exposed early born calves having significantly lower daily weight gain than the late-born calves. However, this might not be entirely due to increased parasitism.

Parasitism level by helminths and weight gain of calves kept in organic and conventional grazing

Sustainable production is a principle in which we must meet the needs of the present without compromising the capacity of future generations. Despite the successful development of pesticides against endo and ectoparasites found in domestic ruminants, these parasites are still the major problem of the herbivore production system. The purpose of this study was to know the population of gastrintestinal parasites and their influence on weight gain of calves kept in organic and conventional grazing. Thus, organic and conventional calves were randomly selected in 2008 and 2009. The fecal egg count (FEC) indentified the following genders of helminths: Haemonchus, Trichostrongylus, Oesophagostomum, Cooperia, Strongyloides, Trichuris and oocysts of Eimeria. There was no significant difference (p>0.05) between FEC in organic and conventional animals. Calves younger than 6 months showed significant higher infection (p<0.05) than calves between 7 and 12 months of age. The weight gain observed during the study was of 327g/day and 280g/day for conventional and organic systems animals, respectively. Consequently, the combination of sustainable practices of grazing associated with the selective application of anthelmintics may be a feasible alternative for nematode control in a conventional system and in transition to an organic one.

Gastrointestinal helminths in calves and cows in an organic milk production system

The main aim of this study was to determine the distribution of populations of gastrointestinal helminths in lactating crossbred cows and calves during the grazing season in an organic milk production system. In addition, the potential importance of the peripartum in relation to the parasite load was examined. Between January 2007 and December 2008, parasitological fecal examinations were performed on cattle belonging to the Integrated Animal Production Program of Embrapa Agrobiology. The cows' parasite load remained low during the study period, and there were no statistical differences (p > 0.05) in comparisons between the seasons. The average egg count showed a positive correlation (0.80) with the peripartum, such that egg elimination per gram (p < 0.05) was higher during the week of labor than during the pre and postpartum periods. Calves showed low parasite loads, with significantly higher egg elimination (p < 0.05) during the winter. The study indicated that infection with gastrointestinal helminths was not a limiting factor for milk production in the organic system. Specifically, it was concluded that the nematode load can be maintained at moderate levels throughout the production system, even in the absence of anthelmintic treatment.

Cryptosporidium spp. in calves and cows from organic and conventional dairy herds

A cohort study was performed to investigate cryptosporidial prevalence and species distribution in 13 organic and 13 conventional dairy herds. Faecal samples were collected from 221 calves and 259 cows. Management routines were recorded at farm inspection and through a questionnaire. Samples were concentrated using sodium chloride flotation and cryptosporidial oocysts were detected by epifluorescence microscopy. Molecular analysis was used to determine species and subtypes. A multivariable model for factors associated with calves being Cryptosporidium spp. positive was built. Cryptosporidium spp.-positive animals were identified in all herds. Prevalences were similar in organic and conventional calves (44·7% vs. 52·3%), as well as in cows (3·1% vs. 3·8%), P > 0·05. Cryptosporidium bovis, C. ryanae and C. parvum were identified. C. ryanae was identified in a calf younger than the described prepatent period. The multivariable model included four significant variables; calf age, cleanliness of bedding, cleaning routines for group pens and farmers' attitudes towards biosecurity.

Use of diagnostic markers to monitor fasciolosis and gastrointestinal nematodes on an organic dairy farm

A 12-month study was conducted to assess and monitor gastrointestinal tract nematodes and liver fluke in cohorts of cattle on a Scottish organic dairy farm. Various diagnostic markers for helminth parasites of cattle from different age groups were assessed monthly from April 2007 to March 2008. First season grazing stock were subjected to significant challenge from Ostertagia ostertagi nematodes as reflected in serum pepsinogen concentrations, which rose markedly in the second half of the grazing season. In addition, plasma albumin concentrations decreased and faecal egg counts (FEC) increased moderately, indicating exposure to both O ostertagi and probably Cooperia oncophora. Second season grazing animals had a peak FEC early in the grazing period, suggestive of a potential carry-over of Ostertagia species infection ('Type 2') during housing. All classes of cattle showed evidence of fluke (Fasciola hepatica) infection. Adult cow exposure to O ostertagi and fluke was estimated via the use of ELISA testing to detect antibodies to O ostertagi and F hepatica and the high levels detected suggested a significant exposure response. Despite low stocking densities and sympathetic grazing management, there was a significant challenge to all grazing stock from gastrointestinal nematodes and liver fluke.

Ostertagia ostertagi in first-season grazing cattle in Belgium, Germany and Sweden: general levels of infection and related management practices

The objective of this study was to determine the prevailing levels of infection with Ostertagia ostertagi in first-season grazing calves and related management factors in three European countries (Belgium, Germany and Sweden). A cross-sectional survey was performed in first-season grazing dairy cattle during 2 consecutive years. Levels of infection with O. ostertagi were assessed by a standardized serum pepsinogen assay at the end of the grazing periods 2006 and 2007 and information on control measures against gastrointestinal nematodes were collected at the same time through a questionnaire. Information was collected from a total of 358 herds in 2006 and 726 herds in 2007. The general infection patterns were similar in the different countries and the 2 years with the majority of the herds having a low (<1 UTyr) or intermediate pepsinogen result (1-3 UTyr) and only 2-6% of the herds having levels of infection that are considered to induce significant production losses (>3 UTyr). The level of nematode control was high in each country, which is illustrated by the widespread use of anthelmintics (69-83% of herds) and the frequent combination of anthelmintic use and control through pasture management (>50% of herds combined two or more protective measures). However, the used control methods showed clear differences between the countries. After taking into account the effect of anthelmintic treatment, herd mean pepsinogen levels were significantly lower in large herds, in calves grazing on a small paddock (vs. pasture) and on mown (vs. non-mown) pastures and if turn out on pasture was postponed. The collected data may serve as a baseline from which we can monitor the methods and success of gastrointestinal nematode control in dairy cattle.

Eimeria and Cryptosporidium in Estonian dairy farms in regard to age, species, and diarrhoea

Eimeria and Cryptosporidium are among the most common bovine parasites in the world, but little is known about them in Estonia. Basic field research is needed to gain insight into pathogen dynamics, providing knowledge for veterinarians and research. A survey of 45 Estonian dairy farms in 15 counties was carried out between 2006 and 2007. Three age groups: <3, 3-12, and >12 months old animals were sampled. Collected faeces were examined by quantitative flotation and Ziehl-Neelsen contrast staining, and species examined morphologically. Selected samples containing Cryptosporidium were additionally examined by polymerase-chain-reaction (PCR) and sequencing to determine genotypes. Twelve species of Eimeria were identified, seven previously unknown in Estonia. Main species in samples were E. bovis (30%), E. zuernii (23%), and E. ellipsoidalis (14%). All herds were infected and animals aged 3-12 months were more commonly infected with Eimeria oocysts (63%) than any other group. Calves <3 months shed most oocyst, but high counts were rare. A negative association (slope=-0.16, p<0.001) was found between the number of animals infected with Eimeria and the age category. Cryptosporidium were detected in 84% of the farms, and C. andersoni and C. parvum were successfully identified. Though prevalences of Cryptosporidium in the age groups were similar to the sample prevalence (30%) an increase in the infections was found with increasing age (p<0.001). Higher diarrhoea scores were negatively associated with Eimeria spp. infection (slope=-0.08, p<0.05), whereas Cryptosporidium could not be associated with the presence of diarrhoea. Frequent low intensity infections of animals in all age groups with both parasites apply a constant stress on the animals with impact on health and production. The Estonian results are different compared to available studies in regard of: older animals commonly being infected, finding of modest oocyst counts, and distribution of Eimeria species.

Management of mastitis on organic and conventional dairy farms

This paper compares management of mastitis on organic dairy farms with that on conventional dairy farms. National standards for organic production vary by country. In the United States, usage of antimicrobials to treat dairy cattle results in permanent loss of organic status of the animal, effectively limiting treatment choices for animals experiencing bacterial diseases. There are no products approved by the US Food and Drug Administration that can be used for treatment of mastitis on organic dairy farms, and usage of unapproved products is contrary to Food and Drug Administration guidelines. In general, organic dairy farms tend to be smaller, produce less, and more likely to be housed and milked in traditional barns as compared with conventionally managed herds. It is difficult to compare disease rates between herds managed conventionally or organically because perception and detection of disease is influenced by management system. To date, no studies have been published with the defined objective of comparing animal health on organic dairy herds with that on conventional dairy herds in the United States. European studies have not documented significant differences in animal health based on adoption of organic management. Few differences in bulk tank somatic cell counts have been identified between organic and conventional herds. Farmers that have adopted organic management consistently report fewer cases of clinical mastitis, but organic farmers do not use the same criteria to detect clinical mastitis. European dairy farmers that adopt organic management report use of a variety of conventional and alternative therapies for treatment and control of mastitis. In the United States, organic farmers treat clinical mastitis using a variety of alternative therapies including whey-based products, botanicals, vitamin supplements, and homeopathy. Organic farmers in the United States use a variety of alternative products to treat cows at dry-off. Virtually no data are available that support the clinical efficacy of any of the alternative veterinary products used for treatment or prevention of mastitis. Some associations between organic management and antimicrobial susceptibility of gram-positive mastitis pathogens have been noted, but overall, few mastitis pathogens from both conventional and organic dairy herds demonstrate resistance to antibiotics commonly used for mastitis control.

A 3-year field evaluation of pasture rotation and supplementary feeding to control parasite infection in first-season grazing cattle—Effects on animal performance

To evaluate non-chemical strategies to control pasture-borne parasites in first-season grazing (FSG) cattle, a 3-year grazing trial was conducted during 2002-2004 on naturally infected pastures on a commercial beef cattle farm in Sweden. A uniform pasture was divided in 4 equal 2 ha paddocks onto each of which 10, 5-9 months old dairy breed steer calves were allocated at turn-out in May each year. Two strategies were evaluated: (1) turn-out onto pasture which had been grazed the previous year by second-season grazing (SSG) steers, followed by a move to aftermath in mid-July (RT) and (2) supplementation with concentrate and roughage for 4 weeks from turn-out (FD). Comparisons were made with an untreated (UT), and an anthelmintic treated control group (DO). Animal parasitology and performance were monitored monthly throughout the 20 weeks grazing period. Additional sampling occasions were performed on day 9 (for coccidia) and 10 weeks after turn-out (mid-July). Due to clinical parasitic gastro-enteritis (PGE), salvage treatments were performed on all animals in group FD approximately 7 weeks after turn-out in 2003 and of three animals in group UT 5 weeks after turn-out in 2004. In 2003, the geometric mean oocyst excretion 9 days after turn-out was approximately 150,000 opg of mainly Eimeria alabamensis in group FD, and in 2004 approximately 180,000 opg in group UT. Apart from the DO group, geometric mean faecal egg counts (FEC) were between 80 and 400 epg 4 weeks after turn-out. Mean serum pepsinogen concentrations (SPC) of approximately 3.6 U tyrosine were recorded in the FD and UT groups from late August 2002. In 2003 and 2004, mean concentrations in these groups were between 4.1 and 7.2 U tyrosine 8 weeks after turn-out. By the end of the three grazing seasons the average weight gain difference compared to the DO group was for FD -29, -38 and -5 kg and for RT -4, -21 and +14 kg, and compared to the UT group -18, +2 and +22 for FD and +7, +19 and +41 kg for group RT. In conclusion, the rotation control strategy showed promising results, whereas the strategic feeding was poor from a parasite control standpoint.

Acute phase proteins in response to Dictyocaulus viviparus infection in calves

Three experiments were carried out to examine the acute phase response, as measured by the acute phase proteins (APP) haptoglobin, serum amyloid A (SAA) and fibrinogen, in calves infected with lungworm, Dictyocaulus vivparus. In addition, eosinophil counts were analysed. Three different dose models were used in 3 separate experiments: I) 250 D. viviparus infective third stage larvae (L3) once daily for 2 consecutive days, II) 100 D. viviparus L3 once daily for 5 consecutive days, and III) 2000 L3 once. All 3 dose regimes induced elevated levels of haptoglobin, SAA and fibrinogen, although there was considerable variation both between and within experiments. A significant increase was observed in all 3 APP at one or several time points in experiment I and III, whereas in experiment II, the only significant elevation was observed for fibrinogen at one occasion. The eosinophil numbers were significantly elevated in all 3 experiments. The results show that lungworm infection can induce an acute phase response, which can be monitored by the selected APP. Elevated APP levels in combination with high numbers of eosinophils in an animal with respiratory disease may be used as an indicator of lung worm infection, and help the clinician to decide on treatment. However, high numbers of eosinophils and low levels of APP do not exclude a diagnosis of lungworm. Thus, lungworm infection may not be detected if measurements of APP are used to assess calf health in herds or individual animals.

Seroprevalence of Dictyocaulus viviparus in first grazing season calves in Sweden

A serological survey was carried out to determine the prevalence and geographical distribution of Dictyocaulus viviparus in calves after their first grazing season in Sweden. A total of 754 animals from 76 randomly selected herds in seven geographical regions were examined between September 24 and December 19, 2001. To get an indication about the geographical distribution of the infection 41 herds with beef-suckler calves were investigated. On each farm, blood was collected from 8 to 10 animals after an average of 26 +/- 24 days post-housing to determine specific IgG1 levels against a possible lungworm sperm antigen that is highly specific against patent infections of D. viviparus. We also investigated the seroprevalence of lungworm infection in relation to cattle management. In one region additional samples were analysed from 35 herds either with: (a) beef-suckling calves that were dewormed at housing, (b) untreated organically raised dairy calves, and finally from conventionally raised dairy calves either, (c) with or, (d) without a prophylactic anthelmintic treatment programme against gastrointestinal parasites on pasture. A questionnaire was used to obtain information about herd size and management, including measures to control nematode parasites on the farm. A total of 86 (11.8%) out of 754 animals had antibodies against D. viviparus, and at least one infected individual was detected in 30 (39.5%) of the 76 herds examined. Lungworm infected animals were found throughout the country and there was no significant differences between regions, although in southern and southwestern Sweden 70.0% of the herds were infected. Furthermore, there were no major differences in the seroprevalence in relation to management. Between 40.0 and 44.4% of the herds were infected irrespective of management, with the exception of calves from organic herds where no seropositive samples were found (0%). This result is in contrast to previous findings of lungworms in Sweden, and indicates that the parasite status on organic farms is diverse.

The effect of treatment with eprinomectin on lungworms at early patency on the development of immunity in young cattle

An experiment was carried out to study the effect of topical application of eprinomectin at early patency on the build up of infection and development of protection against Dictyocaulus viviparus in young cattle. Three groups of six calves were used and parasitological and blood variables were monitored at weekly intervals throughout the trial. At the start of the experiment calves in groups A and B were experimentally inoculated with 100 D. viviparus infective third-stage larvae (L3) for five consecutive days, whereas calves in group C served as uninfected controls. The calves in group A were each treated with eprinomectin (0.5mg/kg bodyweight) in a pour-on formulation at early patency at day 24 post the first inoculation, whereas the calves in groups B and C were left untreated. Seven weeks following anthelmintic treatment all groups were challenged with 1500 L3. Another 4 weeks later the animals were sacrificed and established worms in the lungs were counted. Moderate transient signs of lungworm disease occurred both in groups A and B. However, group B calves were found to be about 8 times more resistant than those in group A, whereas the naive infection controls in Group C was found to be about 35 times more susceptible to infection. Also the ELISA values showed that the course of infection was different between experimental groups. The eosinophil counts prior to and at the time of slaughter indicate that immunity was involved in the protection and the response was correlated with previous exposure and worm load. Weight gains differed significantly, but only between groups A and C and between groups B and C that on an average were approximately 13kg heavier at the termination of the experiment. It was concluded that eprinomectin was effective against established adult lungworms. However, the untreated calves (group B) developed a more marked resistance to lungworms compared to those that were subjected to anthelmintic treatment at early patency (group A). On the other hand, the cumulative number of excreted larvae was on an average 43 times higher in group B as compared to group A. Consequently, infected calves that remain out on pasture should be treated. This will restrain transmission of the parasite despite the fact that immunity is deteriorated.

Evaluation of gastro-intestinal nematode parasite control strategies for first-season grazing cattle in Sweden

A three-year grazing experiment (1998-2000) was conducted with first-season grazing cattle (FSGC) on improved pastures in central-eastern Sweden. Comparison was made between five groups with 10 calves in each group where four of these were set stocked and either (1) untreated, (2) ivermectin bolus treated, (3) subjected to biological control with the nematophagous fungus Duddingtonia flagrans, or (4) treated with a copper wire particle bolus. The fifth treatment was an evasive grazing strategy, whereby untreated calves were turned out onto pasture used by older cattle the previous year and then these calves were moved to silage aftermath in mid-July. To introduce low-levels of parasite infection to the experiment, each animal received a 'priming dose' of approximately 5,000 Ostertagia ostertagi and 5,000 Cooperia oncophora infective third stage larvae immediately prior to the start of the first grazing year of the trial. Results showed that efficient and sustainable parasite control of FSGC was possible to achieve without the use of anthelmintics by using turnout pastures that the previous year had been grazed by older cattle, in combination with a mid-July move to aftermath leys. Biological control also proved beneficial but the efficacy was impaired if high faecal egg counts coincided with rapid dung pat degradation due to heavy rainfall. No indication of parasite control was observed with the copper wire particle bolus. It was also demonstrated that the impact of gastrointestinal (GI) parasitism varied between years and that the level of overwintering contamination is important but likewise, is unpredictable. Although faecal egg counts in 1999 were low, due both to a delayed turnout and drought for the major part of the grazing season, deposited eggs successfully developed to infective larvae and overwintered in large numbers. The population of overwintered infective larvae at the time of turnout in early May played an important role in the course of infection in 2000 and resulted in an average 65 kg advantage of the ivermectin treated calves compared with the untreated calves.Thus, this three-year grazing experiment has emphasised the importance of subclinical gastrointestinal nematode infections in FSGC in Sweden. In addition, the study has shown that adequate parasite control may be achievable without the use of anthelmintics.

Housing, feeding and management of calves and replacement heifers in Swedish dairy herds

A questionnaire was sent to 1500 randomly selected dairy herds in Sweden, asking for general information about the herds, including routines from birth to first calving and also routines at breeding, calving and during the grazing period. Fifty-eight percent of the questionnaires were returned. The preweaned calves were kept in individual calf pens in 68% and in group housing systems in 28% of the herds. Pens with slatted floors were the main housing system for replacement heifers from weaning to breeding, and tie stalls from breeding to first calving. Whole milk was used in 44% and milk replacements in 42% of the herds. The calves received, as a median, 2.5 litres of milk per meal and 2 meals per day. The median age at weaning was 8 weeks. Age was the single most common criteria used for deciding both weaning and breeding time. The median age when the heifers were first turned out to pasture was 6 months. Prophylactic anthelmintic treatment was used by 65% of the herds. The most common diet for replacement heifers before calving was a combination of grain, hay and silage.