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Reaction between albumen and 3,3',5,5'-tetramethylbenzidine as a method to evaluate egg freshness.

The 3,3',5,5'-tetramethylbenzidine colorimetric test is proposed as a method for the evaluation of shell egg freshness. A simplification of the original method was tested on albumen, and the modified method was used to study the development of albumen-tetramethylbenzidine reaction in eggs stored at three temperatures for different times. The stability of the reagent solution and the repeatability of the analytical method were also studied. The reaction mechanism showed the predominant role of iron ions on the colorimetric response, and the secondary role of copper ions added to the reaction mix in order to enhance the response. The response coefficient of variation, due to the natural variability in eggs laid by hens of two breeds and different ages, was 10.3%, which is similar to the value obtained for furosine, but lower than those previously observed for other egg freshness indices such as Haugh Unit and air-cell height.

Animals↗

Lead and cadmium contents in milk, cheese and eggs on the Finnish market.

Lead and cadmium contents were determined in nationally representative samples of low-fat milk, cheese and eggs consumed in Finland. Nationally representative samples of milk and cheese were collected from dairies. Egg samples were collected from the major distributors. Samples of imported cheese and egg products collected in surveillance studies were analysed, together with domestic samples. Lead and cadmium were determined by GFAAS after wet digestion in conc. HNO3. In lead determinations of milk and cheese platinum was employed as the matrix modifier and NH4H2PO4 was employed for the lead determinations of eggs and in all cadmium determinations. Mean lead content was 1.7 micrograms/kg in milk, 17 micrograms/kg in Finnish cheese, 17-60 micrograms/kg in imported cheese, 1 microgram/kg in eggs and 6-72 micrograms/kg in imported dry egg products. Although Finnish consumption in milk, cheese and eggs is high the dietary intake of lead and cadmium from these sources is very low compared with the tolerance limits.

Animals↗

Patch exploitation by female red flour beetles, Tribolium castaneum.

The red flour beetle, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) has had a long association with human stored food and can be a major pest in anthropogenic structures used for the processing and storage of grain-based products. Anthropogenic structures are fragmented landscapes characterized by spatially and temporally patchy resources. Here we investigate the ability of female T. castaneum to evaluate the quality of small patches of food and to adjust the number of eggs they lay per patch (i.e., clutch size) to maximize fitness gains. In multiple choice, paired choice and no choice experiments females tended to lay more eggs in larger amounts of flour. The number of eggs that they lay in a patch of flour was consistent with that predicted to optimize production of adults from that patch (i.e., the 'Lack' clutch size). Progeny size was only significantly impacted in the smallest patch sizes.

Animals↗

Endometrial pattern and thickness associated with pregnancy outcome after assisted reproduction technologies.

The endometrial pattern and thickness was analysed prospectively on the day of administration of human chorionic gonadotrophin (HCG) in 200 in-vitro fertilization (IVF), gamete intra-Fallopian transfer (GIFT) and tubal embryo transfer (TET) cycles. Increasing maturity of the endometrial pattern was positively correlated with oestradiol levels (r = 0.20; P = 0.005), number of mature eggs (r = 0.13; P less than 0.05) and the number of top quality embryos (r = 0.40; P less than 0.001). The endometrial thickness was positively correlated with the number of follicles greater than or equal to 15 mm (r = 0.15; P less than 0.02) and the cycle day on which HCG was administered (r = 0.14; P less than 0.03). It was unaffected by the dose of human menopausal gonadotrophin and was negatively correlated with the use of clomiphene citrate (r = 0.40; P less than 0.001). Fecundity was increased for IVF when the endometrial thickness was greater than or equal to 9 mm (P less than 0.05) and for GIFT and TET when a Type C triple-line endometrial pattern was present (P less than 0.05). Biochemical pregnancies for the combined methods increased from 2.5% of all pregnancies when the endometrial thickness was 9-13 mm, to 27.8% when the thickness was less than 9 mm or greater than 13 mm (P less than 0.01). Biochemical pregnancies occurred in 67% of IVF pregnancies when the endometrial thickness was greater than or equal to 3 mm.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Internal inclusions in brown eggs: relationships with fearfulness and stress.

Tonic immobility reaction and heterophil: lymphocyte ratio (indices of fearfulness and stress, respectively) were studied in hens laying eggs with or without internal inclusions (blood and meat spots). Two brown egg Spanish breed of chickens were used. There were no significant differences between groups in terms of tonic immobility duration. Birds of the group with internal inclusions appeared to be less fearful when defined by the number of inductions to achieve tonic immobility (1.4+/-0.1 vs 1.1+/-0.1; P < 0.01). Tonic immobility duration was significantly shorter in the group of hens with internal inclusions, when only those laying the abnormal egg the day before measurement of tonic immobility were included in this group (264+/-33 vs 395+/-30 s; P < 0.01). There was a significant difference in the heterophil:lymphocyte ratio between the two groups of hens (P < 0.01), mean value being significantly higher in the group with internal inclusions (0.43+/-0.02) than in the control group (0.33+/-0.02). Hens that laid eggs with internal inclusions had significant heterophilia (P < 0.01). Differences were consistent across the breeds. The incidence of internal inclusions was significantly greater (P < 0.001) in eggs with pink shells (an abnormality associated with the effect of stress). The results suggest that the laying of eggs with internal inclusions involves changes in fearfulness and stressfulness of hens.

Animals↗

Dietary methionine intake effects on egg component yield, composition, functionality, and texture profile analysis.

The influence of supplemental Met levels ranging from 413 to 556 mg per hen per d (mg/HD) on liquid egg component yield, composition, and functionality was examined in mature layers (29 wk of age). Egg weight, component yield, solids, and CP content of albumen and yolk were determined. Texture profile analysis, feed ingredient functionality testing, and PAGE were conducted to determine whether increased egg total solids and CP content resulted in altered egg component functionality or electrophoretic protein banding pattern. Albumen component yield increased significantly on a mass basis at 507 and 556 mg/HD Met compared to 413 mg/HD Met. Yolk mass yield was significantly increased at 556 mg/HD Met compared to 413 mg/HD Met. Consumption above 413 mg/HD Met resulted in significantly increased albumen total solids and protein. Yolk solids were not significantly different; however, yolk CP was significantly increased at 507 and 556 mg/HD Met compared to 413 mg/HD Met. Albumen and yolk functionality at 413 and 507 g/HD Met were not significantly different in relation to cake volume or height. Emulsion separation at 120 min was significantly increased for 556 mg/HD Met compared to 413 and 507 g/HD Met. There were no significant differences in hardness or springiness of albumen and yolk gel plugs and electrophoretic protein banding patterns. Increased understanding of the influence of Met on liquid egg yield and composition may provide the egg producer with an effective and advantageous management technique for shell egg production specifically managed to maximize liquid egg product.

Albumins↗

Reveal for Salmonella test system.

The Reveal for Salmonella (RSS) test system is a presumptive qualitative test that detects the presence of Salmonella organisms in foods within 21 h total testing time, allowing the user to release negative products 24 h earlier than when using other rapid test kits. Foods are enriched with a proprietary resuscitation medium called Revive and then selectively enriched with either Selenite Cystine or Rappaport-Vassiliadis selective media. The enriched culture is used to inoculate the RSS detection device, which initiates a lateral flow through a reagent zone containing anti-Salmonella antibodies conjugated to colloidal gold particles that capture antigens present in the culture. The antigen-antibody complex migrates farther and is captured by an additional anti-Salmonella antibody, causing the colloidal gold to precipitate and form a visual line, indicating a positive result. A procedural control line also will form regardless of the presence of Salmonella organisms to indicate the test is working properly. Existing AOAC Official Methods for Salmonella organisms require a 48 h enrichment before testing. Hence, a food product has to be held before release, adding extra cost to the company and the consumer. The RSS test system was evaluated by quantitative spiking studies. Although AOAC encourages inclusion of naturally contaminated foods, almost all microbiological AOAC validation studies have been performed with artificially contaminated foods for absolute control over the study. The RSS test system is designed to test many food types for Salmonella organisms and has a limit of detection of 5-10 colony-forming units (cfu)/25 g with a false-negative rate of < 1% and a false-positive rate of < 5.0%. It showed an 81% overall agreement with the traditional procedure of the U.S. Department of Agriculture's Food Safety Inspection Service.

Animals↗

Assisted reproductive technology surveillance--United States, 2002.

PROBLEM/CONDITION: In 1996, CDC initiated data collection regarding assisted reproductive technology (ART) procedures performed in the United States, as mandated by the Fertility Clinic Success Rate and Certification Act (FCSRCA) (Public Law 102-493, October 24, 1992). ART includes fertility treatments in which both eggs and sperm are handled in the laboratory (i.e., in vitro fertilization and related procedures). Patients who undergo ART treatments are more likely to deliver multiple-birth infants than women who conceive naturally. Multiple births are associated with increased risk for mothers and infants (e.g., pregnancy complications, premature delivery, low-birthweight infants, and long-term disability among infants). REPORTING PERIOD: 2002. DESCRIPTION OF SYSTEM: : CDC contracts with the Society for Assisted Reproductive Technology (SART) to obtain data from ART medical centers located in the United States. Since 1997, CDC has compiled data related to ART procedures. RESULTS: In 2002, a total of 115,392 ART procedures were reported to CDC. These procedures resulted in 33,141 live-birth deliveries and 45,751 infants. Nationally, 74% of ART procedures used freshly fertilized embryos from the patient's eggs; 14% used thawed embryos from the patient's eggs; 8% used freshly fertilized embryos from donor eggs; and 3% used thawed embryos from donor eggs. Overall, 42% of ART transfer procedures resulted in a pregnancy, and 34% resulted in a live-birth delivery (delivery of one or more live-born infants). The highest live-birth rates were observed among ART procedures using freshly fertilized embryos from donor eggs (50%). The highest numbers of ART procedures were performed among residents of California (15,117), New York (13,276), Massachusetts (8,631), New Jersey (7,744), and Illinois (7,492). These five states also reported the highest number of infants conceived through ART. Of 45,751 infants born through ART, 53% were born in multiple-birth deliveries. The multiple-birth risk was highest for women who underwent ART transfer procedures using freshly fertilized embryos from either donor eggs (42%) or their own eggs (35%). Number of embryos transferred, embryo availability (an indicator of embryo quality), and patient's age were also strong predictors of multiple-birth risk. Approximately 1% of U.S. infants born in 2002 were conceived through ART. Those infants accounted for 17% of multiple births nationally. The percentage of ART infants who were low birth rate ranged from 9% among singletons to 95% among triplets or higher order multiples. The percentage of ART infants born preterm ranged from 15% among singletons to 97% among triplets or higher order multiples. INTERPRETATION: Whether an ART procedure resulted in a pregnancy and live-birth delivery varied according to different patient and treatment factors. ART poses a major risk for multiple births. This risk varied according to the patient's age, the type of ART procedure performed, the number of embryos transferred, and embryo availability (an indicator of embryo quality). PUBLIC HEALTH ACTION: ART-related multiple births represent a sizable proportion of all multiple births nationally and in selected states. Efforts should be made to limit the number of embryos transferred for patients undergoing ART. In addition, adverse infant health outcomes (e.g., low birthweight and preterm delivery) should be considered when assessing the efficacy and safety of ART.

Female↗

Assisted reproductive technology surveillance--United States, 2003.

PROBLEM/CONDITION: In 1996, CDC initiated data collection regarding assisted reproductive technology (ART) procedures performed in the United States, as mandated by the Fertility Clinic Success Rate and Certification Act (FCSRCA) (Public Law 102-493, October 24, 1992). ART includes fertility treatments in which both eggs and sperm are handled in the laboratory (i.e., in vitro fertilization and related procedures). Patients who undergo ART treatments are more likely to deliver multiple-birth infants than women who conceive naturally. Multiple births are associated with increased risk for mothers and infants (e.g., pregnancy complications, premature delivery, low-birthweight infants, and long-term disability among infants). REPORTING PERIOD COVERED: 2003. DESCRIPTION OF SYSTEM: CDC contracted with the Society for Assisted Reproductive Technology (SART) to obtain data from ART medical centers located in the United States. Since 1997, CDC has compiled data related to ART procedures. RESULTS: In 2003, a total of 122,872 ART procedures were reported to CDC. These procedures resulted in 35,785 live-birth deliveries and 48,756 infants. Nationwide, 74% of ART procedures used freshly fertilized embryos from the patient's eggs; 14% used thawed embryos from the patient's eggs; 8% used freshly fertilized embryos from donor eggs; and 4% used thawed embryos from donor eggs. Overall, 42% of ART transfer procedures resulted in a pregnancy, and 35% resulted in a live-birth delivery (delivery of one or more live-born infants). The highest live-birth rates were observed among ART procedures using freshly fertilized embryos from donor eggs (51%). The highest numbers of ART procedures were performed among residents of California (15,911), New York (15,534), Massachusetts (8,813), Illinois (8,676), and New Jersey (8,299). These five states also reported the highest number of infants conceived through ART. Of 48,756 infants born through ART, 51% were born in multiple-birth deliveries. The multiple-birth risk was highest for women who underwent ART transfer procedures using freshly fertilized embryos from either donor eggs (40%) or their own eggs (34%). Number of embryos transferred, embryo availability (an indicator of embryo quality), and patient's age were also strong predictors of multiple-birth risk. Approximately 1% of U.S. infants born in 2003 were conceived through ART. Those infants accounted for 18% of multiple births nationwide. The percentage of ART infants who were low birthweight ranged from 9% among singletons to 94% among triplets or higher order multiples. The percentage of ART infants born preterm ranged from 15% among singletons to 97% among triplets or higher order multiples. INTERPRETATION: Whether an ART procedure resulted in a pregnancy and live-birth delivery varied according to different patient and treatment factors. ART poses a major risk for multiple births. This risk varied according to the patient's age, the type of ART procedure performed, the number of embryos transferred, and embryo availability (an indicator of embryo quality). PUBLIC HEALTH ACTIONS: ART-related multiple births represent a sizable proportion of all multiple births nationwide and in selected states. Efforts should be made to limit the number of embryos transferred for patients undergoing ART. In addition, adverse infant health outcomes (e.g., low birthweight and preterm delivery) should be considered when assessing the efficacy and safety of ART.

Adult↗

Available amino acid score for evaluating protein quality of foods.

Amino acid scores corrected for true digestibility of individual amino acids (as determined by rat balance method) were termed "available amino acid scores" in the present investigation. Available amino acid scores were calculated for 7 protein sources and their 10 supplementary or complementary mixtures which have been tested in collaborative amino acid and rat growth assays for evaluating protein quality. The available amino acid scores were as follows: casein + methionine (100); egg white (100); rapeseed protein concentrate, RPC (94); casein (93); beef (89); soya assay protein, SAP (62); pea flour (61); whole wheat flour, WW (38); SAP + methionine (88); pea flour + methionine (72); WW + lysine (67); WW + casein (84); WW + egg white (79); WW + RPC (65); WW + beef (77); WW + SAP (70); and WW + pea flour (75). These scores were similar to the collaborative relative NPR values; the differences were less than 10 units (2-9 units) in most cases. The positive correlation (r = 0.92) between available amino acid scores and relative net protein ratio (RNPR, a rat growth method) values was highly significant (P less than 0.01) and the origin of the regression line (y = 0.92x + 1.88) was not significantly different from zero. Amino acid bioavailability has previously been a problem, preventing widespread acceptance of amino acid score. Available amino acid score solves this problem.

Amino Acids↗

Effect of spinning and additional cross-linking with dialdehyde starch or aluminum ions on the digestibility and quality of casein-Vicia faba protein isolate mixtures.

Studies were made in adult rats using an isotopic 15N method. Whole egg, wheat, casein and Vicia faba protein isolate served as reference proteins. The diets were isonitrogenous and feed intake was adjusted to the maintenance energy level. Variations in true N digestibility were small (91.8-96.1%). The amount of metabolic fecal nitrogen in animals receiving the diet containing wheat was 9.4 mg/100 g body weight compared with 4.9-5.8 mg in the other diets. The differences in nutritional quality for maintenance between proteins of plant and animal origin were small. However, spinning (alkaline treatment) and additional cross-linking with aluminum ions or dialdehyde starch affected the nutritional quality for maintenance.

Aluminum↗

Assessment of the protein quality of nine northern adapted yellow and brown seed coated soybean cultivars by amino acid analysis.

Accurate and detailed amino acid determinations were carried out on nine northern adapted soybean cultivars to ascertain whether their amino acid profiles could be used as potentially useful indices for assessing their protein quality. The cultivars were Maple Amber, Maple Donovan, Maple Glen, Maple Isle, Maple Presto, Maple Ridge, and three brown seed coat near-isogenic lines, Maple Presto Brown, Maple Ridge Brown, and Maple Arrow Brown. Their total protein and amino acid composition were compared with those of an established cultivar, Maple Arrow. Mean protein values for the new cultivars ranged from 30.1 to 33.1% compared to Maple Arrow, which was 33.2%. The total nitrogen content was also variable among these cultivars, ranging from 5.0 to 5.4%. All nine Maple series soybean cultivars were higher in their essential amino acid (EAA) content, that is, EAA(9) = 45.2-46.5%, than the FAO/WHO reference protein pattern value of EAA(9) = 33.9%, for a 2-5-year-old child. Each of the nine new soybean cultivars was limited only in methionine and to a lesser extent in valine and isoleucine and had a protein digestibility corrected amino acid score of 91% for all cultivars, compared to the value of egg protein (97%). These results suggest that the most accurate evaluation of protein quality in soybeans, and possibly other legumes and cereals, is by the protein digestibility-corrected amino acid score.

Amino Acids↗

Fertility and sperm quality of broiler breeder males infected with subgroup J avian leukosis virus.

In order to assess the effects of subgroup J avian leukosis virus (ALV-J) on semen quality, broiler breeder males were separated by ALV-J status (ALV-J positive = POS, ALV-J negative = NEG) at 44 wk of age. Of the 249 males originally placed at 1 day of age, 101 (40.6%) died by 43 wk of age. Observations of tumor expression and high mortality suggest that many of the males that died prior to 44 wk of age were infected with ALV-J. From 47 to 56 wk of age, hens were inseminated every third week with 7.5 x 10(7) sperm. Fertility and hatch data were collected by incubating eggs laid during the 2 wk postinsemination (WPI). The number of sperm that penetrated the perivitelline membrane of the ovum was determined from eggs laid on the eighth day postinsemination. Sperm mobility index (SMI) was determined at 58 and 60 wk of age from all males producing semen. Whereas SMI and sperm hole penetration measurements indicated that the sperm quality from treatments POS and NEG were similar, fertility was significantly greater in the POS treatment during the first (89.0% vs. 79.0%) and second WPI (59.3% vs. 45.0%). However, because of numerically higher hatch of fertile from the NEG group, the percentage of hatch of eggs set was similar between groups. These data suggest that ALV-J status of caged males has no influence on sperm quality or hatchability of eggs.

Aging↗

Timing of the calcium intake and effect of calcium deficiency on behaviour and egg laying in captive great tits, Parus major.

The calcium demand of egg-laying birds is much higher than in other vertebrates during reproduction. We showed elsewhere that a low level of calcium availability can greatly affect the eggshell quality and reproduction of free-living passerines. However, there are few data on calcium demand and calcium intake in relation to egg laying and behaviour and egg-laying performance under conditions of calcium shortage in nondomesticated birds. We examined these aspects in an experiment with captive great tits, Parus major, on a diet deficient in calcium, with or without snail shells as an additional calcium source. More than 90% of the calcium intake for egg production took place during the egg-laying period. Females ingested about 1.7 times as much calcium as they deposited in eggshells. Removing the snail shells after the first egg resulted in eggshell defects and interruptions of laying after 1-3 d. Females without snail shells doubled their searching effort and started to burrow in the soil and to eat sand, small stones, and their own eggs. Most calcium was consumed in the evening, probably to supplement the calcium available from the medullary bone with an additional calcium source in the gut during eggshell formation. The results demonstrated that eggshell formation requires accurate timing of the calcium intake and that obtaining sufficient calcium is time-consuming, even in calcium-rich environments. These factors pertaining to calcium intake greatly affect the ability of birds to collect sufficient calcium for eggshell formation in calcium-poor areas.

Animals↗

Quantification and control of the spatiotemporal gradients of air speed and air temperature in an incubator.

Around the optimal incubator air temperature only small spatiotemporal deviations are allowed. However, air speed and air temperature are not uniformly distributed in the total volume of the incubator due to obstruction of the eggs and egg trays. The objectives of this research were (1) to quantify the spatiotemporal gradients in temperature and velocity and (2) to develop and validate a control algorithm to increase the uniformity in temperature during the entire incubation process. To improve the uniformity of air temperature, the airflow pattern and the air quality need to be controlled more optimally. These data show that the air temperature between the eggs at a certain position in a large incubator is the result of (1) the mean air temperature of the incubator; (2) the exchange of heat between the egg and its micro-environment, which is affected by the air speed at that certain position; (3) the time-variable heat production of the embryo; and (4) the heat influx or efflux as a result from the movement of hot or cold air in the incubator toward that position, which is affected by the airflow pattern. This implies that the airflow pattern needs to be controlled in a more optimal way. To maximize the uniformity of air temperature, an active and adaptive control of the three-dimensional (3-D) airflow pattern has been developed and tested. It was found to improve the spatiotemporal temperature distribution. The chance of having a temperature reading in the interval from 37.5 to 38.1 degrees C increased by 3% compared to normal operating conditions.

Air Movements↗

Evidence for mediation of a neuronal interaction by a behaviorally active peptide.

Egg laying hormone, a peptide neurohormone with an approximate molecular weight of 6000, was isolated from the region of the abdominal ganglion of Aplysia that contains the neuroendocrine bag cells and purified by gel filtration chromatography, isoelectric focusing, and dialysis. A 1-min local application of egg laying hormone to the identified neuron R15 produced prolonged (greater than 1 hr) augmentation of impulse activity in this neuron. The distinctive quality and prolonged duration of the response are apparently identical to the previously described response to electrically elicited bag cell activity. The results provide evidence that egg laying hormone is the mediator of this prolonged neuronal interaction.

Animals↗

The effect of different levels of nonphytate phosphorus with and without phytase on the performance of four strains of laying hens.

A 4 x 7 factorial experiment was conducted to determine the effect of different nonphytate phosphorus (NPP) regimens with and without phytase on performance of four strains of laying hens. The strains used were Babcock B300, DeKalb Delta White, Hy-Line W36, and ISA-White. The birds of T1 (Treatment 1), control diet, were fed a diet with 0.45% NPP for the entire experiment (20 to 63 wk of age). The birds of T2 were fed a NPP regimen of 0.25% for Phase 1 (20 to 35 wk of age), 0.2% for Phase 2 (36 to 51 wk of age), and 0.15% for Phase 3 (52 to 63 wk of age). The birds of T3 and T4 were fed a NPP regimen similar to T2 plus 150 or 300 units phytase/kg diet, respectively. The birds of T5 were fed a NPP regimen of 0.2, 0.1, and 0.1% for Phases 1, 2, and 3, respectively. The birds on T6 and T7 were fed a NPP regimen similar to T5, with 150 and 300 units phytase/kg diet, respectively. The criteria for evaluating the effect of dietary treatments were production performance, shell quality, bone ash, and total P excretion. Production traits were drastically reduced and mortality was drastically increased when the birds of T5 were fed a diet with 0.1% NPP during Phase 2 (36 to 51 wk of age). Increasing the NPP level of this treatment from 0.1 to 0.45% during Phase 3 restored the production traits almost to the control level during this phase of the experiment. The NPP regimen of 0.2-0.1-0.1% plus either level of phytase (T6 and T7) restored most of the traits for the entire experiment to the control level (T1), except egg production (EP) and the nonprolapse mortality. Bone ash also remained significantly lower than the control group with this NPP regimen plus the higher level of phytase (T7). Production traits were reduced, and nonprolapse mortality was increased due to the use of a NPP regimen of 0.25-0.2-0.15% without phytase (T2) for the entire experiment. The NPP regimen of 0.25-0.2-0.15% plus the lower level of phytase (T3) restored all the traits except EP to the control level for the entire experiment. The only treatment that maintained performance of all the strains comparable to their controls for the entire experiment was a NPP regimen of 0.25-0.2-0.15% plus the higher level of phytase (T4). Total P excretion of birds fed this NPP regimen was reduced by 55.6% as compared to the control group. The data generally indicated that the higher level of phytase was more effective than the lower level in restoring the performance of birds fed the low-P diets to the control level. Numerous interactions existed among strain x diet for various traits throughout the experiment, indicating the NPP requirement for maintaining production performance may be different among strains.

6-Phytase↗

Serum spermagglutinins and semen quality in the bull.

Three bulls injected with homologous semen or testis material developed spermagglutinins in serum while one control bull inoculated with egg white did not. In one bull a high spermagglutinin titre was associated with allergic epididymitis, a decreased proportion of motile spermatozoa, and an increased proportion of tall abnormalities. The palpable lesion persisted for 35 days, the spermagglutinin titre and semen abnormalities for a further 2 months. No change in semen quality was associated with the lower serum spermagglutinin titres in the other two treatment bulls or over comparable periods of time in the control bull. No naturally occurring spermagglutinins were found in a population of 50 bulls with varying semen qualities at an artificial breeding centre.

Agglutinins↗