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The inactivation of ERG3, a gene encoding sterol Δ5,6-desaturase (essential for ergosterol biosynthesis), is a known mechanism of in vitro resistance to azole antifungal drugs in the human pathogen Candida albicans. ERG3 inactivation typically results in loss of filamentation and attenuated virulence in animal models of disseminated candidiasis. In this work, we identified a C. albicans clinical isolate (VSY2) with high-level resistance to azole drugs in vitro and an absence of ergosterol but normal filamentation. Sequencing of ERG3 in VSY2 revealed a double base deletion leading to a premature stop codon and thus a nonfunctional enzyme. The reversion of the double base deletion in the mutant allele (erg3-1) restored ergosterol biosynthesis and full fluconazole susceptibility in VSY2, confirming that ERG3 inactivation was the mechanism of azole resistance. Additionally, the replacement of both ERG3 alleles by erg3-1 in the wild-type strain SC5314 led to the absence of ergosterol and to fluconazole resistance without affecting filamentation. In a mouse model of disseminated candidiasis, the clinical ERG3 mutant VSY2 produced kidney fungal burdens and mouse survival comparable to those obtained with the wild-type control. Interestingly, while VSY2 was resistant to fluconazole both in vitro and in vivo, the ERG3-derived mutant of SC5314 was resistant only in vitro and was less virulent than the wild type. This suggests that VSY2 compensated for the in vivo fitness defect of ERG3 inactivation by a still unknown mechanism(s). Taken together, our results provide evidence that contrary to previous reports inactivation of ERG3 does not necessarily affect filamentation and virulence.

A mitochondrial sulphonylurea-sensitive, ATP-sensitive K+ channel (mitoKATP) that is selectively inhibited by 5-hydroxydecanoate (5-HD) and activated by diazoxide has been implicated in ischaemic preconditioning. Here we re-evaluate the evidence for the existence of this mitoKATP by measuring changes in light scattering (A520) in parallel with direct determination of mitochondrial matrix volumes using 3H2O and [14C]sucrose. Incubation of rat liver and heart mitochondria in KCl medium containing Mg2+ and inorganic phosphate caused a decrease in light scattering over 5 min, which was accompanied by a small (15-30 %) increase in matrix volume. The presence of ATP or ADP in the buffer from the start greatly inhibited the decline in A520, whilst addition after a period of incubation (1-5 min) induced a rapid increase in A520, especially in heart mitochondria. Neither response was accompanied by a change in matrix volume, as measured isotopically. However, the effects of ATP and ADP on A520 were abolished by carboxyatractyloside and bongkrekic acid, inhibitors of the adenine nucleotide translocase (ANT) that lock the transporter in two discrete conformations and cause distinct changes in A520 in their own right. These data suggest that rather than matrix volume changes, the effects of ATP and ADP on A520 reflect changes in mitochondrial shape induced by conformational changes in the ANT. Furthermore, we were unable to demonstrate either a decrease in A520 or increase in matrix volume with a range of ATP-sensitive K+ channel openers such as diazoxide. Nor did glibencamide or 5-HD cause any reduction of matrix volume, whereas the K+ ionophore valinomycin (0.2 nM), produced a 10-20 % increase in matrix volume that was readily detectable by both techniques. Our data argue against the existence of a sulphonylurea-inhibitable mitoKATP channel.

A 5-year-old Quarter Horse stallion was admitted for cryptorchidectomy. Abnormalities were not found on physical examination, except for an undescended left testis. Cryptorchidectomy was performed, using an inguinal approach. The tail of the epididymis was in the inguinal canal, and the testis was adjacent to the internal inguinal ring. The testis was dark reddish purple to black, resulting from torsion at the level of the body of the epididymis. On histologic examination, the left testis was necrotic, except for the tunica albuginea and tunica vaginalis visceralis covering the testis. Intra-abdominal testicular torsion developed without signs of abdominal pain and resulted in necrosis of the affected testis. If cryptorchidectomy had not been performed, it is likely that the horse would have been found to be monorchid. Unrecognized intra-abdominal testicular torsion may be the cause of monorchidism in some horses.

The objectives of this study were to examine the effects of feeding zinc-treated soybean meal (Zn-SBM) on ruminal fermentation patterns and duodenal AA flows in steers fed diets based on corn silage and corn. Six steers (385 kg) fitted with ruminal, duodenal, and ileal cannulas were used in a replicated 3 x 3 Latin square design experiment with 14-d periods. Diets were supplemented with solvent-extracted soybean meal (SBM), Zn-SBM, or a 50:50 combination (CP basis) of SBM:Zn-SBM. Ruminal escape N content of SBM and Zn-SBM were 30.0 and 57.0%, respectively, based on 12-h Dacron bag incubation. Protein sources provided approximately 30% of total CP in diets containing 12.6% CP (DM basis). Dry matter intake was equalized throughout the study at 2.2% of average initial BW. Total N flow at the duodenum was similar (P = .47) among treatments, but a trend (P = .15) for increased nonmicrobial N flow occurred when SBM and Zn-SBM were fed in combination. Micobial N flow and true efficiency of microbial CP synthesis were not affected by treatment (P = .87 and .37, respectively). Ruminal fermentation characteristics generally were unaffected (P.10) by protein source. A positive quadratic response (P.06) was observed for total and essential AA flows to the small intestine because flows of total and essential AA from ruminally undegraded dietary protein tended (P = .12) to increase when SBM and Zn-SBM were fed in combination. Absorption of AA from the small intestine also showed a positive quadratic (P.06) response for SBM:Zn-SBM. Microbial AA flow to the small intestine was similar (P = .87) among treatments.(ABSTRACT TRUNCATED AT 250 WORDS)

The objective of this study was to examine the effect of combining ruminally degradable and undegradable CP sources on ruminal microbial protein synthesis and postruminal N and amino acid (AA) flows in steers. Six steers fitted with ruminal, duodenal, and ileal cannulas were fed diets containing corn silage and high-moisture corn supplemented with urea, soybean meal (SBM), dry corn gluten feed (DCGF), a combination of corn gluten meal and blood meal (CB), or SBM and DCGF in combination with CB. Estimated ruminal N escapes for SBM, DCGF, and CB were 32, 25, and 68%, respectively. Supplemental CP sources supplied 35 to 40% of diet CP (12.5% CP diets). Dry matter intake was adjusted to 2.3% of BW for each steer in each period. Total N flow at the duodenum decreased (P.01) when the diet was supplemented with urea vs other proteins due to decreased (P.01) flow of nonmicrobial N. However, microbial N and AA flows were greater (P.05) for urea than for other protein supplements. Disappearance of OM and NDF in the stomach decreased (P.07) or was numerically lower but nonmicrobial N at the duodenum increased (P.08) as CB replaced SBM or DCGF in the diet. Protein source had little effect on ruminal fermentation characteristics except that ruminal ammonia N (NH3N) concentration was higher (P.05) for urea than for other treatments. Total AA and essential AA flows to and disappearance from the small intestine increased (P.06) as CB replaced DCGF. However, substituting CB for SBM had little effect on intestinal flows and disappearance of AA. These data suggest that source of ruminally degradable CP can influence the efficacy of feeding ruminally degradable and undegradable CP in combination. In general, source of supplemental CP had a greater effect on the quantity than on the profile of absorbable AA supplied to the duodenum.

CHICKENS cannot survive very long when deprived of water. A ten percent loss of body water through dehydration and excretion results in serious physical disorders (Romanoff and Romanoff, 1949). Dehydration is particularly noticeable in the shanks, and some mortality may result as reported by Marble and Jeffrey (1955). Hoffman and Johnson (1946) reported chicks that have been without water can be readily identified because in their eagerness to drink they wet their plumage and have a bedraggled appearance for some time afterward. Kare and Biely (1948) placed New Hampshire chicks on diets containing .9 to 4.0 percent salt, and deprived them of water four to six hours per day. The water-restricted chicks compensated by drinking more when water was before them which resulted in approximately the same water:feed ratios as the controls with water ad libitum. In a study conducted by Ross (1960) one-week-old New Hampshire chicks were given…

DEVELOPMENT of a refractory condition leading to failure of the junco to produce eggs in an environment of long light days was observed by Wolfson (1952). A similar inability of turkey females to respond in egg production when exposed to long light days was reported by Harper and Parker (1957, 1960, 1962), Clayton and Robertson (1960), McCartney et al. (1961), Leighton and Shoffner (1961a, b, 1964), Wilson et al. (1962) Shoffner and Leighton (1962), Shoffner et al. (1962), Marsden et al. (1962), Ogasawara et al. (1962), and Wolford et al. (1963). In the above research control of the photoperiod to reduce light exposure prior to sexual maturity of turkey females was effective in terminating refractoriness. While the above experiments demonstrated a method of improving year around egg production of turkeys through a controlled light environment, it necessitated adequate buildings. The use of hormones to terminate refractoriness in turkey females hatched…

Three experiments were conducted to determine the effect of reserpine in terminating light refractoriness when the drug was incorporated in feed of young turkey hens 24 to 28 weeks of age. Results show that the drug at levels of 0.5, 0.75, 1.0 and 2.0 p.p.m. for two, three or four weeks produced inconsistent responses as measured by egg production when compared to restricted light to control refractoriness. Fertility, hatchability and embryonic morphology were not effected by the treatments. Body weight and feed consumption also were unaffected.

FERTILITY of eggs from flock matings of chickens is generally highest in the winter and spring months and decreases in the summer and fall as shown by Upp and Thompson (1927) and numerous other investigators since. It has also been reported by Parker and McSpadden (1943) and Wheeler and Andrews (1943) that chicken semen volumes decline during the summer and fall months. The above observations lead to the speculation that fertility in flock matings may be related to the volume of semen produced by the males. Malmstrom (1943) observed that fertility in flock matings declined when temperatures exceeded 47°F. and stated that this decline was probably because of reduced semen production in the males. Jones and Lamoreux (1942) observed that White Leghorn cockerels of a high-fecundity strain produced greater volume of semen than those of a low-fecundity strain. They also observed that fertility from natural matings was higher in the…

In studying the effect of nutrition on fertility in adult male chickens (Arscott and Parker, 1967), we observed that some White Leghorn males appeared more nervous and agitated than others during the process of collecting semen. It was considered possible that this might result in lower semen volumes. The purpose of this experiment was to determine if the inclusion of a tranquilizer in the diet of these males affected semen volume and other reproductive characteristics. A review of the literature provided very little information specifically related to adult male chickens. Hewitt and Reynolds (1957) reported that 7 p.p.m. of reserpine in the diet of adult ring-neck pheasants prevented fighting in cocks. A decrease in fertility also was observed. Whether or not this effect was attributed to either the males or the females was not determined. Adverse effects on egg production, fertility and hatchability have been noted also with turkey breeders …

Abomasal fistulas were corrected surgically in 9 adult Holstein cows. Six cows had a history of right paramedian abomasopexy (RPA), and 2 cows had had a percutaneous abomasopexy using the blind-stitch technique (BSA). Fistulas developed from 2 weeks to 12 months after the RPA or BSA. In 1 cow, history was not available beyond 2 years, and no surgery had been performed in that time. All fistulas were in the right paramedian area and were draining blood and/or ingesta from necrotic abomasal tissue (8 cows) or ruminal tissue (1 cow). Surgery was performed immediately in cows with consistent hemorrhage from the fistulated tissue (4 cows). Surgery was delayed to reduce rumen contents if bleeding was absent or considered negligible (4 cows) or to stabilize the patient (1 cow). General anesthesia was used in 7 cows, local anesthesia in 2 cows. Outcome following the fistula resection was successful in the 7 cows discharged from the clinic. The occurrence of abomasal fistulation is probably related to nonabsorbable sutures penetrating the abomasal lumen during the abomasopexy procedure resulting in infection of the incision or body wall.

A recently castrated horse was examined because of preputial and ventral abdominal swelling, prolapse of the preputial fold, and serosanguinous fluid dripping from the external urethral orifice. After a poor response to initial medical management, a urethral laceration was found during exploratory surgery. Half of the ventral portion of the corpus cavernosum penis had been transected. Primary closure was followed by healing without complications.

Four rodent cell lines were exposed to 2450 MHz microwave radiation at a Specific Absorption Rate (SAR) of 103.5 +/- 4.2 W/kg for varying lengths of time at 37 degrees, 40 degrees, 42 degrees and 45 degrees C. mRNA was extracted from microwave-exposed and sham-exposed cells and dot blotted or Northern blotted to nitrocellulose. Radioisotope labelled DNA probes of oncogenes, heat shock protein or long terminal repeat sequences were hybridized to the mRNA, and the resulting autoradiographs analyzed for differences in levels of mRNA expression between exposed and nonexposed samples. With the cell lines and probes used in this study no significant differences in mRNA expression were observed after microwave exposure.

Shell-less or soft-shelled eggs, which are covered with little or no shell substance, are quite frequently produced by domestic fowls (Hewitt, 1939). Jaap and Muir (1968) reported that 82 to 90 percent of broiler-type pullets, depending on the strain, laid some defective eggs. Their results also showed that 3.7 to 7.0 percent of the total yolks were laid as either soft shelled or shell-less eggs. Hewitt (1939) suggested that the cause of shell-less eggs is either a failure of the glands in the shell-secreting portion of the oviduct, or violent peristalsis which hastens the egg through this region before a shell can be formed. Other causes suggested include the possibility of the bird being disturbed or some irritation in the oviduct (Romanoff and Romanoff, 1949). Results of Buckner et al. (1922) showed that calcium starvation is not necessarily a causative factor in the production of shell-less eggs, as was once…

To determine whether sterility of adult male chickens fed a diet high in linoleic acid and low in vitamin E was permanent or could be reversed by supple mental vitamin E, 3 groups of 8 White Leghorn males were fed for a 40-week experi mental period as follows: group 1, a high linoleic acid (7.3% )-high vitamin E (166.3 mg/kg) diet; group 2, a high linoleic acid-low vitamin E (4.3 mg/kg) diet; and group 3, treated as group 2 from zero to 28 weeks and as group 1 from 28 to 40 weeks. The following results were obtained: 1) The adverse effect of the high linoleic acidlow vitamin E diet on fertility and semen concentration was confirmed. 2) The addi tion of vitamin E to the high linoleic acid diet at 28 weeks restored fertility to the1 level obtained from males receiving vitamin E throughout the trial. 3) Semen concen tration was improved following the addition of vitamin E to the diet at 28 weeks. 4) No meaningful differences on semen volume, hatchability of fertile eggs, feed con sumption, mortality, or body and testes weights were observed with males fed the various diets. The results indicate that the low fertility and semen concentration of male chickens fed a diet high in linoleic acid but low in vitamin E are reversible fol lowing vitamin E supplementation. Arscott et al. (1) reported that adult White Leghorn male chickens fed a diet high in linoleic acid but low in vitamin E and ethoxyquin for a 25-week experimen tal period experienced low fertility and reduced semen concentration. When such diets were supplemented with vitamin E or ethoxyquin, no adverse effects were noted. Also a diet low in both linoleic acid and vitamin E did not appear detrimental. Increasing the number of sperm insemi nated from males receiving a diet high in linoleic acid and low in vitamin E failed to improve fertility. Information on the permanence of sterility was not obtained. Adamstone and Card (2) reported ste rility, as evidenced by testicular degenera tion, in male chickens after having been fed a vitamin E-deficient diet for a 2-year period. Although evidence for permanent sterility was not presented, the irreversible nature of sterility resulting from vitamin E-deficient diets for male chickens appears in the literature (3). In this respect, Evans and Burr (4) and Mason (5) have reported on the irreversibility of the steril ity observed in male rats fed diets deficient in vitamin E; however, Bryan and Mason (6) were unable to demonstrate testicular degeneration in male mice fed diets de ficient in vitamin E for 400 days. The per manence of the testicular degeneration noted with guinea pigs fed vitamin Edeficient diets (7) apparently is not known (8). It was the purpose of the present experi ment to determine whether supplemental vitamin E would reverse the sterility noted in male chickens fed a diet high in linoleic acid.

Adult male chickens were fed diets low in linoleic acid, vitamin E and ethoxyquin or high in linoleic acid with or without added vitamin E or ethoxyquin for 25 weeks. Fertilizing capacity and sperm concentration of semen were adversely affected with males fed the high linoleic acid diet without vitamin E or ethoxyquin. The addition of vitamin E or ethoxyquin to the high linoleic acid diet overcame these adverse effects. The low linoleic acid diet without vitamin E and ethoxyquin had no adverse effect on fertilizing capacity and concentration of semen. No differences were evident for males fed any of the diets as far as semen volume, hatchability of fertile eggs, body or testes weights or feed consumption were concerned. During the 26th and 27th weeks increasing the number of sperm inseminated failed to improve fertility of the males fed the diet high in linoleic acid without vitamin E. The results indicate that diets high in linoleic acid but without vitamin E affect fertilizing capac ity as well as the number of sperm produced. Adamstone and Card ( 1) reported testicular degeneration resulting after a vita min E-deficient diet was fed to Rhode Island Red males for a 2-year period. Al though no differences were observed at one year, an adverse effect on fertilizing capacity was noted with a limited number of males after 2 years. More recently Machlin et al. (2) reported adverse effects on fertility as well as egg production of White Leghorn layers fed diets low in vitamin E but containing a high level of linoleic acid. They showed that lowered fertility and egg production were overcome by addition of vitamin E or ethoxyquin to the diet. In the absence of the high level of linoleic acid as well as vitamin E and ethoxyquin no adverse effects on fertility or egg production could be observed during the 6 weeks of their experiment. The relationship of vitamin E to linoleic acid metabolism has been reviewed by Scott (3). Evidence is cited indicating that vitamin E functions as a biological antioxidant that protects against encephalomalacia in chicks by preventing the breakdown of linoleic acid to 12-oxo-cis-9-octadecenoic (keto) acid. Whether or not the same relationship exists with adult poultry has not been established, but the data re ported with layers (2) suggest such a pos sibility. In view of a previous interest in the area of nutrition as related to male fertility (4), the present experiment was undertaken to determine whether linoleic acid would ex ert a detrimental effect on fertilizing ca pacity of adult male chickens fed diets with or without vitamin E or ethoxyquin.

Summary. Three groups of White Leghorn cocks were fed rations containing 2557, 2956 and 3353 kcal/kg of metabolizable energy over a 40-week period. The first, the control ration, provided the approximate maintenance level when daily intake did not exceed 90 g/bird. Semen was collected ten times from each male by abdominal massage during the experiment and the fertilizing capacity of each ejaculate was determined by artificial insemination. At the end of the experiment, the males on the 2956- and 3353-kcal rations weighed 12\m=.\5%and 18% more than at the start. Both the thickness of the layer of abdominal\x=req-\ wall fat and the weight of this layer plus the gizzard fat increased as caloric intake increased. Obesity, within the limits obtained in these experiments without artificially stimulated hyperphagia or forced\x=req-\ feeding, had no significant effect on testicular weights or on the volume and sperm density of semen. There were no consistent significant differences in the fertilizing capacity of the semen, as determined by artificial insemination, nor in the hatchability of fertile eggs.

REVIEWS of the literature concerning testicular response of birds to photostimulation have been written by Lamoreux (1943a), Romanoff (1960) and Amoroso and Marshall (1960). Lamoreux also reported results showing that semen production and testis size in Leghorn cockerels were related to the length of the daily light period. Recently, Parker and McCluskey (1964) showed that sexually mature male fowls produce satisfactory volumes of potent semen under as little as 1 hour of daily light exposure. The purpose of the investigations reported herein was to determine the effect of rearing cockerels under daily light exposures ranging from 1 to 13 hours on ages at which semen was first produced, and on their subsequent fertilizing capacity in natural matings. EXPERIMENTAL PROCEDURE Four groups of Delaware chicks hatched in November, 1960, were reared from time of hatching under four regimes of 1, 3, 9 and 13 hours of daily light. There was no…

Moore and Byerly (1942) and Malmstrom (1943) showed that chicken hens laid a lower percentage of fertile eggs if they had a hard-shelled egg in the uterus at the time of artificial insemination. This suggests that for high fertility, hens should not be inseminated when a high percentage of them have hard-shelled eggs in their oviducts. In naturally mated flocks both Gracewski and Scott (1943) and Parker (1950) observed that fertility of eggs was higher when mating was restricted to the afternoon as compared with the forenoon. Parker (1945) and Bornstein et al. (1960) reported higher fertility from p.m. than from a.m. artificial inseminations although a less pronounced difference was reported by the latter. To determine the effects of the time of artificial inseminations and of the length of the following egg-saving period on fertility two experiments were conducted with White Leghorn chickens. In the first, 16 rows of 15…

Previous investigations have shown that the percentage of fertile eggs laid following artificial insemination of chicken hens in the morning is lower than that from hens inseminated in the afternoon (Parker, 1945; Bornstein et al., 1960). A generally accepted explanation is that more hens have hard-shelled eggs in their uteri in the morning. Several investigators have reported that fertility of hens with hard-shelled eggs in their uteri at the time of insemination is lower than that from other hens (Moore and Byerly, 1942; Malmstrom, 1943; Parker, 1945; Bornstein et al., 1960). However, more recent results (Parker and Arscott, 1965) showing that fertility from hens inseminated at 9 p.m. was comparable to that of hens inseminated at mid-afternoon are not in accord with the above explanation since most of the hens inseminated at 9 p.m. had eggs in their uteri at the time of insemination—many with hard shells. This suggests…