Feeding strategies on certified organic dairy farms in Wisconsin and their effect on milk production and income over feed costs.

The purposes of this study were (1) to analyze and categorize certified organic Wisconsin dairy farms based on general farm characteristics and feeding strategies during the course of 2010, and (2) to evaluate herd milk production and income over feed costs (IOFC). An on-site survey containing sections on farm demographics, feeding, grazing, and economics was conducted on 69 farms (12.6% survey response rate). A nonhierarchical clustering method using 9 variables related to general farm characteristics, feed supplementation, and grazing was applied to partition the farms into clusters. A scree plot was used to determine the most appropriate number of clusters. Dry matter intake was approximated based on farmer-reported total amounts of feed consumed (feed offered less refusals). Milk production was evaluated using reported milk rolling herd averages (RHA). Income over feed costs was calculated as milk sales minus feed expenses. The farms in clusters 1 (n=8) and 3 (n=32), the large and small high-input farms, respectively, included more feed ingredients in their lactating cow diets and relied more heavily on concentrates than farms in other clusters. Cows on these farms were predominantly Holstein. Clusters 1 and 3 had the highest RHA (6,878 and 7,457 kg/cow per year, respectively) and IOFC ($10.17 and $8.59/lactating cow per day, respectively). The farms in cluster 2 (n=5) were completely seasonal, extremely low-input farms that relied much more heavily on pasture as a source of feed, with 4 out of the 5 farms having all of their operated land in pasture. Farms in cluster 2 relied on fewer feeds during both the grazing and nongrazing seasons compared with farms in the other clusters. These farms had the lowest RHA and IOFC at 3,632 kg/cow per year and $5.76/lactating cow per day, respectively. Cluster 4 (n=24), the partly seasonal, moderate-input, pasture-based cluster, ranked third for RHA and IOFC (5,417 kg/cow per year and $5.92/lactating cow per day, respectively). Breeds other than Holstein were used more prevalently on farms in clusters 2 and 4. Results indicated extreme variation in animal breed, structure, and feeding strategies among Wisconsin organic dairy farms. Feeding strategies appeared to be major determinants of RHA and IOFC. These findings may serve current organic and transition farmers when considering feeding management changes needed to meet organic pasture rule requirements or dealing with dietary supplementation challenges.

A simple model for learning stereotactic skills in ultrasound-guided amniocentesis.

BACKGROUND: Amniocentesis is an important procedure for antenatal diagnosis but requires stereotactic skill acquisition that may be facilitated by the use of a model. TECHNIQUE: A model using a gelatin mold with "targets" within is created. The model is used to facilitate development of stereotactic skills and to demonstrate technique principles for ultrasound-guided amniocentesis. EXPERIENCE: The model has been incorporated into an educational program for antenatal diagnosis within a residency and provides a reasonable simulation of clinical features important in learning genetic amniocentesis. CONCLUSION: The use of this model augments the learning of important skills needed for ultrasound-guided amniocentesis.

Direct administration of chlordecone into Japanese quail eggs has persistent effects on conditioned behavior of adults.

Chlordecone (0.1 to 10 mg) or corn oil vehicle was injected into Japanese quail eggs on day 1 of incubation. Higher doses (0.5-10 mg per egg) produced tremor and ataxia at hatching and dose-related decreases in hatchability and survivability. Doses lower than 0.25 mg per egg had no effects. Gonad weights were not affected at 12 weeks of age. A second study examined the effect of injecting 0.5 mg of chlordecone into the egg on day 1, 3, 7 or 14 of incubation. Chlordecone-induced tremor was present at hatching regardless of the day of injection. Significant decreases in hatchability and increases in embryonic mortality were seen when chlordecone was injected on day 1 of incubation. Survivability to 5 weeks of age was decreased in birds receiving chlordecone on day 1 or 3 of incubation. At 75 to 84 days of age, egg production was decreased only in birds injected on day 1 of incubation. The offspring from these studies were mated and the hatchability and reproductive capability of these birds was studied at 75 to 84 days of age and found to be not significantly affected. In a third study, birds exposed to 0.5 mg of chlordecone or vehicle on day 1 of incubation were trained as adults in a food reinforced operant task. Exposure to chlordecone affected performance during the first 3 of 15 days of a match-to-sample task. The baseline response rate of these animals on a food reinforced random interval 60 sec schedule was then determined. During the last two weeks of asymptotic performance, chlordecone-exposed birds had a significantly lower rate of responding than controls. These data indicate that in ovo exposure to chlordecone can have significant long-term effects on conditioned behavior and egg production, particularly if exposure occurs on day 1 of incubation.

Field safety and efficacy of in ovo administration of HVT + SB-1 bivalent Marek's disease vaccine in commercial broilers.

The field safety and efficacy of a bivalent Marek's disease (MD) vaccine (herpesvirus of turkeys + strain SB-1) administered in ovo were evaluated. The vaccine was administered to commercial broiler chicken eggs using Embrex's INOVOJECT automated egg-injection system. Comparisons were made with a conventional method of vaccination, in which the vaccine was administered subcutaneously to chicks at hatching. In ovo administration of the vaccine at day 17.5-18.5 of incubation significantly reduced the number of culled chicks, early mortality, and overall mortality during the grow-out period compared with conventional vaccination. However, hatchability was significantly lower in in ovo-treated chicks. Overall livability and feed efficiency were higher in the in ovo-treated chicks than in conventionally vaccinated chicks. Total field-caused condemnations and condemnations due to airsacculitis and septicemia/toxemia were also lower in the in ovo-vaccinated chicks. No difference in the leukosis (MD) condemnation rate was observed between the two treatment groups. In ovo vaccination provided 93.25% protection against challenge with a very virulent strain of MD virus (strain RB1/B); by comparison, the conventional vaccination method provided 89.58% protection.

Papular mucinosis associated with acquired immunodeficiency syndrome.

Papular mucinosis, also known as lichen myxedematosus, is a rare, idiopathic disorder in which focal deposits of mucin accumulate in the dermis. It has been previously reported in two patients with human immunodeficiency virus infection; we describe a third such case and note the presence of a granuloma adjacent to the mucin deposit. We also comment on other clinical manifestations of cutaneous mucin deposition and granuloma formation in human immunodeficiency virus infection.

Age, geographic, and temporal distribution of fecal shedding of Cryptosporidium parvum oocysts in cow-calf herds.

OBJECTIVE: To evaluate fecal shedding of Cryptosporidium parvum from California cow-calf herds with respect to age, geographic region, temporal effects, and association with watery feces. ANIMALS: Cows and calves from 38 beef cow-calf operations. PROCEDURE: Fecal specimens were collected and examined for C parvum oocysts, using immunofluorescent microscopy. Associations between age, geographic region, month of collection, watery feces, and likelihood of shedding C parvum were evaluated. RESULTS: 3.9% of cattle were shedding C parvum oocysts. Prevalence of shedding among calves ranged from 0 to 13%, and was 0.6% among cattle > or = 12 months old. The odds of shedding C parvum among 2-month-old calves were 41 times greater than among cattle > 4 months old. The odds of shedding C parvum among cattle tested in May were 8.7 times greater than among cattle tested during June, July, or August. The odds of infected individuals having watery feces were 3 to 4 times greater than for noninfected individuals, but the etiologic fraction was only 8 to 9%. CONCLUSIONS AND CLINICAL RELEVANCE: Substantial fecal shedding of C parvum by cow-calf herds was limited to calves 1 to 4 months old, with low prevalence detected in older animals. Risk of contamination of watersheds with C parvum was limited to those periods when young calves were in the herd. Although the odds of having watery feces were greater for animals infected with C parvum than for noninfected animals, the low etiologic fraction suggests that most calves with watery feces were not infected with C parvum.

The effects of incubator carbon dioxide level on turkey hatchability.

Four experiments involving CO2 level in single-stage incubators were conducted at a commercial turkey hatchery. Carbon dioxide was injected into incubators to a level of .3% during the first 10 days of incubation. Noninjected control incubators were maintained at a .1% CO2. Eggs from the injected incubators had a higher hatchability and lower early, late, and malpositioned embryonic mortality. No difference in hatchability was found between .3 and .5% CO2 concentrations for the first 10 days of incubation. Carbon dioxide injection for the first 5 days of incubation decreased hatchability when compared to CO2 injection for the first 10 days. Carbon dioxide injection for the first 14 days of incubation resulted in no difference in hatchability from injection for the first 10 days. The artificial addition of CO2 to single-stage turkey incubation systems may be of economic importance in commercial hatcheries because of its effect on hatchability.

Effects of low intensity red light on testicular recrudescence in Japanese quail.

Experiments were conducted to determine if sighted and blind plumage color mutants of Japanese quail elicit comparable testicular recrudescence when exposed to long daily photoperiods of low intensity red light. Quail exhibiting testicular regression after exposure to 8 hr of light daily for several weeks were blinded via bilateral ocular enucleation. A control group was not enucleated. Two light intensities, 1.4 and 2.8 lx, were applied to half of the birds in each group during a 16 hr daily photoperiod for several weeks. Enucleated birds and birds under the 2.8 lx intensity had greater testis weights than the controls. Birds were also blinded by optic tract sectioning, and a .7 lx red light intensity treatment was included. Greater testis weights were found in birds under higher light intensities. Three plumage pigmentation mutants, sex linked incomplete albino, white and wild-type, were exposed to 8 hr of light daily for either 4 or 8 weeks to induce testicular regression. They were then exposed to the three light intensities for 3 weeks. Higher intensities and albinism resulted in greater testicular recrudescence only when the regression interval was 8 weeks, even though testicular regression appeared after 4 weeks. The absence of eyes or plumage pigmentation, resulting in an increased exposure of the encephalon for extraretinal light reception, may have effected greater testicular recrudescence. Severed optic tracts with tract eyes did not produce this response to light, indicating that the eyes may play a role in mediating the photosexual reflex in quail. Lower intensities may have resulted in reduced tissue penetration and testicular growth. A definite threshold intensity necessary to elicit testis growth was not found.

Factors affecting broiler processing parameters and plasma corticosterone.

Two experiments were conducted to determine the influence of broiler strain, sex, and age on resting plasma corticosterone levels and the latter's relationship to various broiler production and processing parameters. In Experiment 1, strain and sex differences in 58-day farm weight (FWT), dressed carcass weight (DC), yield (Y), abdominal fat (AF), abdominal fat expressed as a percentage of DC (PAF), and plasma corticosterone (C) measures were assessed in five commercial broiler strains fed a lower [3086 kcal metabolizable energy (ME)/kg] versus higher (3306 kcal ME/kg) energy ration. The higher energy diet was formulated and used to produce excess abdominal fat. In Experiment 2, the effect of broiler age (4, 6, and 8 weeks) on resting plasma C was determined. Results of Experiment 1 indicated that although strain significantly influenced AF, and although feeding the higher energy diet significantly elevated FWT, DC, Y, AF, and PAF, strain and dietary energy effects on plasma C were nil. However, a significant strain X dietary energy interaction on plasma C levels was observed. Likewise, although female broilers had greater PAF measures than male birds, sex did not influence resting plasma C values. Plasma C was not correlated to AF measures. Experiment 2 results showed plasma C at 6 (3.3 ng/ml) and 8 weeks (2.9 ng/ml) was significantly depressed from the 4-week (4.9 ng/ml) sampling. Thus, future studies involving adrenal functioning in broilers should take into consideration the influence bird age might have on interpretation of results.

Effects of eggshell cuticle removal and incubation humidity on embryonic development and hatchability of broilers.

The effects of eggshell cuticle removal and two levels of incubation humidity 28.3 C [50% relative humidity (RH)] and 30.0 C (55% RH) wetbulb temperature (WB) on embryonic mortality and hatchability were determined from broiler hatching eggs laid during 38, 42, 48, and 54 weeks of age. Variables measured were: egg weight loss during the first 17 days of incubation, hatch at Days 19.5 and 20.5 of incubation, hatch of fertile eggs, stage of embryonic mortality, and chick weight at 21.5 days of incubation. Day 0 to 17 percentage egg weight loss was increased when the incubation humidity was lowered and the loss was greater than that observed after cuticle removal. A greater percentage of chicks hatched on Day 19.5 at 28.3 C than at 30.0 C WB. The percentage hatch of 38-week fertile eggs was improved at the higher humidity; the higher humidity also decreased late dead and increased pipped embryonic mortalities. Cuticle removal decreased early dead and increased late dead mortality. At Week 38 cuticle removal and lower humidity resulted in a decrease in chick weight at 21.5 days of incubation. For Weeks 42, 48, and 54 combined, pipped mortality was increased by higher humidity and late dead mortality was increased by cuticle removal. Water loss from the egg was increased by cuticle removal or by lowering incubation humidity from 30.0 C to 28.3 C WB, or by both, but lowering humidity was more effective. Changes in humidity and cuticle removal may affect vital gas exchange to different degrees.(ABSTRACT TRUNCATED AT 250 WORDS)

Characterization of different hematological responses during molts induced by zinc or fasting.

Single Comb White Leghorn hens were induced to molt by complete fasting for 11 days (FAST) or feeding a layer ration that contained 20,000 ppm zinc as zinc oxide for 11 days (ZINC). In both cases hens lost approximately 30% of their initial body weight. A control (CON) group was maintained. At 4, 8, 12, 18, and 42 days after initiation of the treatments, total erythrocyte numbers (TRBC), percent packed cell volume (PCV), mean corpuscular volume, hemoglobin (Hb), mean corpuscular hemoglobin (MCHb), and mean corpuscular hemoglobin concentration (MCHC) were determined. Erythrocytes were characterized as reticulocytes, intermediate Stage VII erythrocytes, or mature Stage VIII erythrocytes. The FAST hens exhibited significantly increased PCV through 18 days, which was not exhibited by ZINC hens. The FAST treatment increased TRBC on Days 8 and 12 and decreased TRBC on Day 42 while ZINC decreased TRBC on Day 4 and increased TRBC on Day 12. The FAST hens exhibited decreased Hb on Day 42, as reproduction resumed. Both ZINC and FAST hens exhibited decreased MCHb and MCHC on Day 12. Percentages of reticulocytes were decreased at Day 4 by FAST and increased at Days 8 and 18 by ZINC. Stage VII erythrocytes were decreased on Days 4 and 12 in FAST hens whereas ZINC hens exhibited a decrease on Day 4 and an increase on Days 8 and 18. Concomitantly, FAST hens exhibited an increase in Stage VIII erythrocytes on Days 4 and 12, whereas an increase on Day 4 and decreases on Days 8 and 18 were observed in ZINC hens.(ABSTRACT TRUNCATED AT 250 WORDS)

Plasma corticosterone radioimmunoassay and levels in the neonate chick.

The objective was to develop and validate a rapid, precise plasma corticosterone radioimmunoassay using a commercially available antiserum, for use in Gallus domesticus. Sample preparation consisted of sequential 2,2,4-trimethylpentane and dichloromethane extraction to partition progestins and glucocorticoids, respectively. Progesterone, 11 beta-Hydroxyprogesterone, and deoxycorticosterone significantly cross reacted with the antiserum used. However, progesterone was effectively removed prior to assay by the 2,2,4-trimethylpentane plasma washings while 11 beta-Hydroxyprogesterone and deoxycorticosterone interference is doubtful for reasons discussed. Standard curve data showed a linear range from 0 to 150 pg by log-logit transformation with a 5 pg assay sensitivity. Mean percent unlabeled corticosterone recovery was 96% with intraassay and interassay coefficients of variation being 3.75 and 5.62%, respectively. The assay was utilized to characterize corticosterone fluctuations during day one post hatch in broiler chicks. Method of blood collection, rapid decapitation vs. heart stab, resulted in no difference in mean plasma corticosterone levels. Corticosterone levels differed over a 24 hr sampling period, such that highest levels were found upon receipt of the chicks at the hatchery (approximately 20 ng/ml) and 20 hr later (approximately 11 ng/ml). Lowest plasma corticosterone concentrations occurred from 10 to 14 hr (approximately 6 ng/ml) after receipt of the chicks.

Egg production in four generations of paired Japanese quail.

Four generations of Japanese quail were hatched in succession starting with the progeny of an Athens Randombred quail colony. In each generation quail were maintained in cages as male-female pairs. The photoperiod was 16 hr of light per day with feed and water available ad libitum. From 6 to 20 weeks of age mortality, egg production, fertility, hatchability, and progeny livability were improved over previously published reports of reproduction in colony cages. Mortality decreased while age at 50% hen-day production, total number of eggs produced, and hatchability increased from the 1st to the 4th generation. This information may be of interest to researchers and commercial producers of Japanese quail.

Effect of prefeeding on physiological parameters associated with turkey poult mortality.

A commercially available antibiotic and nutrient solution was prefed by gavage into the crops of newly hatched poults, which were then brooded under standard conditions of continuous lighting, 35-C temperatures, and ad libitum feed. Treated poults exhibited higher feed consumption, hematocrits, and total red blood cells during the week following the prefeeding regime. Prefeeding partially ameliorated the typically low hematological parameters that have been associated previously with early poult mortality. The results of this study suggest that prefeeding an antibiotic and nutrient solution significantly improves the welfare of poults during the 1st week after hatching.

Hematological indices of turkey embryos incubated at high altitude as affected by oxygen and shell permeability.

Turkey eggs (Meleagris gallopavo) were incubated at an altitude of 1,707 m to test the effects of oxygen supplementation and increased eggshell permeability by removal of shell cuticle on embryonic hematology. Turkey embryo hematological indices measured were red blood cell count (RBC), hemoglobin concentration, packed cell volume, mean cellular volume, mean cellular hemoglobin, and percentage of reticulocytes. Although hemoglobin concentration measured during pipping increased as expected by increasing RBC, no significant differences were observed between oxygenation, or permeability treatments, or their interaction. Under the high altitude conditions of the present experiment, increased hemoglobin concentrations in all treatments corresponded to increased numbers of erythrocytes with constant mean cellular hemoglobin. None of the remaining hematological indices examined was affected by oxygen or permeability treatments. It was concluded that turkey embryos incubating at 1,707-m elevation make no additional changes in hemoglobin concentrations during the plateau stage in oxygen consumption (25, 26, and 27 days of incubation) when exposed to increased oxygen tension (151 mm Hg versus 135 mm Hg) or increased eggshell permeability (19.9 mg H2O/day per mm Hg versus 23.2 mg H2O/day per mm Hg).

Effects of adrenocorticotropin and dietary ascorbic acid on delayed type hypersensitivity to human gamma globulin in chickens.

Three trials were conducted to assess the effects of adrenocorticotropin (ACTH) and dietary ascorbic acid (AA) on delayed type hypersensitivity (DTH) to human gamma globulin (HGG) in chickens. Broiler chicks received AA at 0, 150, or 300 mg/Kg of feed (ppm) continuously from hatching, were sensitized at 5 wk of age to HGG emulsified in complete Freund's adjuvant, and 2 wk postsensitization, were challenged with an intradermal injection of HGG into a wattle. Birds from each AA group received ACTH at either HGG sensitization, challenge, or both. There were uninjected controls and a vehicle control group, which received gelatin at both sensitization and challenge. The ACTH and gelatin injections were given at 12-h intervals beginning 12 h prior to HGG. Responses to DTH were determined as wattle indices. In all three trials, birds that received ACTH at challenge exhibited a DTH response at 18 and 24 h postchallenge that suppressed, compared with that of controls. Birds that received ACTH at sensitization had a greater wattle response than that of birds that received ACTH at challenge, and this effect was enhanced by dieting AA. In Trial 2, birds that received ACTH at sensitization had a greater wattle response at 18 h post HGG challenge than that of controls. Total leucocyte numbers were unaffected; however, heterophil:lymphocyte ratios were lower in birds that received ACTH at sensitization than in birds that received ACTH at challenge and birds that received ACTH at challenge had fewer lymphocytes. Whether given at challenge or at sensitization, ACTH decreased plasma AA when measured at those times. The 300 ppm level of AA increased plasma AA concentration. Adrenal gland and wattle AA levels were unaffected; however, spleen AA concentration was lower in birds given ACTH at challenge.

Effect of phlebotomy on reticulocyte numbers in Japanese Quail.

Hematological changes were studied in response to a phlebotomy of 30% of the estimated total blood volume in 5-week-old Coturnix coturnix japonica. Blood samples, femoral bone marrow samples, and blood and marrow erythroid cell differential counts were collected at 0 (nonphlebotomized), 1, 3, 6, 24, and 72 hr postphlebotomy. The samples were collected only once from each bird. Total peripheral erythrocyte numbers, percent hematocrit, and hemoglobin levels were decreased at 1, 3, 6, and 24 hr. The relative percentage of peripheral erythrocytes with little or no reticulum was not affected by phlebotomy. With the exception of mean cellular hemoglobin concentration, all of the hematological values measured in the peripheral blood had returned to nonphlebotomized, 0 hr levels at 72 hr postphlebotomy. However, in the bone marrow, a marked reticulocytosis was found at 72 hr postphlebotomy.

Research note: in ovo administration of a competitive exclusion culture treatment to broiler embryos.

Exposure of chicks to salmonellae in the hatchery and hatchery environment limits the effectiveness of a competitive exclusion (CE) culture treatment. Therefore, in an attempt to apply treatment before chicks are exposed to salmonellae, the CE culture was introduced in ovo to unhatched embryos. An undefined, anaerobically grown CE culture, derived from cecal contents of healthy adult chickens, was diluted 1:1,000 or 1:1,000,000 and inoculated either into the air cell or beneath the inner air cell membrane of 17-day-old incubating hatching eggs. The treated chicks were more resistant than untreated chicks to varying challenge levels of Salmonella typhimurium, indicating that it may be possible to initiate protection of chicks to salmonellae challenge prior to hatching into a contaminated environment.

Hematological response of immunized and serially bled Japanese quail.

Sexually mature female Japanese quail (Coturnix coturnix japonica) were immunized by an intravenous injection with .5 ml of a 7.5% suspension of Chukar partridge (Alectoris graeca chukar) red blood cells (CRBC). Blood samples were collected either serially from one group of quail or a single time from separate groups of quail at 0 (nonimmunized), 3, 6, and 9 days post-immunization. Total anti-CRBC hemagglutinin titers (HA) were measured by a microhemagglutinin procedure. Selected hematological variables were also measured. Mean HA was not affected by serial blood sampling. Total erythrocyte numbers, percent hematocrit, and hemoglobin levels were depressed in serially bled quail at 3 days postimmunization. Reticulocytosis was found in serially bled quail at 6 days postimmunization.

Circulating levels of corticosterone in the serum of developing chick embryos and newly hatched chicks.

Circulating levels of corticosterone were determined in chick embryos from 10 to 21 days of incubation using eggs from a Leghorn breeder flock. In Experiment 1, eggs were incubated from 10 to 20 days for daily embryonic blood collection. To verify stage of development with day of incubation, embryo right middle toe lengths were measured concurrent with blood sampling. Serum from three embryos was pooled into one sample and the corticosterone content of 10 samples per day of incubation was determined using a radioimmunoassay procedure. The levels of corticosterone from day 10 to 14 fluctuated slightly and then increased rapidly until 16 days of incubation. At this time serum corticosterone remained relatively constant through day 18 with an apparent increasing trend up to day 20. The use of toe lengths to assure no day-to-day overlap in embryonic development proved effective. In Experiment 2, newly hatched (day 21) chicks were sorted into four 3-hr periods ranging from early to late hatching. Blood samples were collected from five individual chicks during four 15-min sampling periods for each of the four hatch times. Serum corticosterone levels were not affected by sampling periods or hatch times.